Endocrine system | anatomy | Britannica

Endocrine system, any of the systems found in animals for the production of hormones, substances that regulate the functioning of the organism. Such a system may range, at its simplest, from the neurosecretory, involving one or more centres in the nervous system, to the complex array of glands found in the human endocrine system.

The glands of the human endocrine system.

Encyclopædia Britannica, Inc.

Comparative endocrinologists investigate the evolution of endocrine systems and the role of these systems in animals’ adaptation to their environments and their production of offspring. Studies of nonmammalian animalshave provided information that has furthered research in mammalian endocrinology, including that of humans. For example, the actions of a pituitary hormone, prolactin, on the control of body water and salt content were first discovered in fishes and later led to the demonstration of similar mechanisms in mammals. The mediating role of local ovarian secretions (paracrine function) in the maturation of oocytes (eggs) was discovered in starfishes and only later extended to vertebrates. The important role of thyroid hormones during embryonic development was first studied thoroughly in tadpoles during the early 1900s. In addition, the isolation and purification of many mammalian hormones was made possible in large part by using other vertebrates as bioassay systems; that is, primitive animals have served as relatively simple, sensitive indicators of the amount of hormone activity in extracts prepared from mammalian endocrine glands. Finally, some vertebrate and invertebrate animals have provided “model systems” for research that have yielded valuable information on the nature of hormone receptors and the mechanisms of hormone action. For example, one of the most intensively studied systems for understanding hormone actions on target tissues has been the receptors for progesterone and estrogens (hormones secreted by the gonads) from the oviducts of chickens.

An understanding of how the endocrine system is regulated in nonmammals also provides essential information for regulating natural populations or captive animals. Artificial control of salmon reproduction has had important implications for the salmon industry as a whole. Some successful attempts at reducing pest insect species have been based on the knowledge of pheromones. Understanding the endocrinology of a rare species may permit it to be bred successfully in captivity and thus prevent it from becoming extinct. Future research may even lead to the reintroduction of some endangered species into natural habitats.

Evolution of endocrine systems

The most primitive endocrine systems seem to be those of the neurosecretory type, in which the nervous system either secretes neurohormones (hormones that act on, or are secreted by, nervous tissue) directly into the circulation or stores them in neurohemal organs (neurons whose endings directly contact blood vessels, allowing neurohormones to be secreted into the circulation), from which they are released in large amounts as needed. True endocrine glands probably evolved later in the evolutionary history of the animal kingdom as separate, hormone-secreting structures. Some of the cells of these endocrine glands are derived from nerve cells that migrated during the process of evolution from the nervous system to various locations in the body. These independent endocrine glands have been described only in arthropods (where neurohormones are still the dominant type of endocrine messenger) and in vertebrates (where they are best developed).

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It has become obvious that many of the hormones previously ascribed only to vertebrates are secreted by invertebrates as well (for example, the pancreatic hormone insulin). Likewise, many invertebrate hormones have been discovered in the tissues of vertebrates, including those of humans. Some of these molecules are even synthesized and employed as chemical regulators, similar to hormones in higher animals, by unicellular animals and plants. Thus, the history of endocrinologic regulators has ancient beginnings, and the major changes that took place during evolution would seem to centre around the uses to which these molecules were put.

Vertebrates (phylum Vertebrata) are separable into at least seven discrete classes that represent evolutionary groupings of related animals with common features. The class Agnatha, or the jawless fishes, is the most primitive group. Class Chondrichthyes and class Osteichthyes are jawed fishes that had their origins, millions of years ago, with the Agnatha. The Chondrichthyes are the cartilaginous fishes, such as sharks and rays, while the Osteichthyes are the bony fishes. Familiar bony fishes such as goldfish, trout, and bass are members of the most advanced subgroup of bony fishes, the teleosts, which developed lungs and first invaded land. From the teleosts evolved the class Amphibia, which includes frogs and toads. The amphibians gave rise to the class Reptilia, which became more adapted to land and diverged along several evolutionary lines. Among the groups descending from the primitive reptiles were turtles, dinosaurs, crocodilians (alligators, crocodiles), snakes, and lizards. Birds (class Aves) and mammals (class Mammalia) later evolved from separate groups of reptiles. Amphibians, reptiles, birds, and mammals, collectively, are referred to as the tetrapod (four-footed) vertebrates.

The human endocrine system is the product of millions of years of evolution. and it should not be surprising that the endocrine glands and associated hormones of the human endocrine system have their counterparts in the endocrine systems of more primitive vertebrates. By examining these animals it is possible to document the emergence of the hypothalamic-pituitary-target organ axis, as well as many other endocrine glands, during the evolution of fishes that preceded the origin of terrestrial vertebrates.

Endocrine System – an overview

Introduction

The endocrine system, along with the nervous system, comprise the primary regulators of body metabolism. While the nervous system acts through electrical impulses and neurotransmitters, the endocrine system operates through chemical messengers called hormones. Hormone production is regulated by a chain of choreographed interactions of many endocrine organs. As a response to physiological and environmental stress, hormones are synthesized and secreted in a timely and quantitative manner. They travel in the bloodstream to different parts of the body to elicit characteristic cellular responses through hormone-specific receptors in target endocrine organs. Upon binding to receptors at target organs, the hormone–receptor complex initiates a cascade of signal transduction reactions, which ultimately modulate expressions of genes, thus regulating physiological and cellular reactions that are essential for reproduction, growth, development, immune reactions, and neurobehavioral functions.

Furthermore, hormone production is controlled by negative feedback mechanisms. When there is sufficient concentration of a hormone in circulation, a control mechanism will send signals back to the hormone-producing organ to inhibit further hormone production. This mechanism prevents excessive stimulation and maintains the stability of the cellular status.

Many environmental factors, including the light cycle, temperature, naturally occurring ingredients in food, and anthropogenic pollutants, interact with the endocrine system and influence hormone production. Substances with the ability to interfere with hormone levels in the endocrine system, however, do not necessarily pose any health risk for humans and other organisms. The endocrine system has the capacity to tolerate moderate external challenges by evoking the above-described adaptable control/feedback mechanisms, thus maintaining functional homeostasis of the body. However, deleterious health effects could occur when the control mechanisms of equilibrium are overwhelmed by excessive amounts of exposure to endocrine disruptors.

Endocrine dysfunction could result from having either an excessive or insufficient amount of hormone production or failure to induce proper cellular responses. Excessive amounts of hormones may be caused by overproduction, rapid release from storage, decreased rate of metabolism or decreased excretion, while insufficient amount of hormone production may be caused by decreases in hormone synthesis or release, increased rate of metabolism or rapid excretion. Cellular injury of endocrine organs and altered enzymatic activities of hormone synthesis and metabolism could be the underlying etiology of endocrine toxicity. Endocrine dysfunction may also result from exposure to substances with structures similar to hormones that are capable of binding to receptors, thus either mimicking the function of a hormone or inhibiting the function of the normal hormone–receptor complex. An endocrine toxic substance may also change the way hormones are transported in circulation by adhering to or changing the amount of hormone-binding protein. In such cases, either the total concentration of a hormone or the amount in free form (i.e. biologically available form) can be altered. Furthermore, hormones are also involved in the differentiation and development of interrelated endocrine organs and the nervous systems. The potential of a substance to cause developmental effects depends not only on the amount of exposure, but also on the timing of exposure in an organism’s stage of life. During gestation and prepuberty, morphological and functional development in a fetus and young animal are highly sensitive to endocrine-disrupting agents.

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2.4 The Endocrine System

LOQ 2-6 How does the endocrine system transmit information and interact with the nervous system?

endocrine [EN-duh-krin] system the body’s “slow” chemical communication system; a set of glands that secrete hormones into the bloodstream.

hormones chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues.

So far, we have focused on the body’s speedy electrochemical information system. But your body has a second communication system, the endocrine system (FIGURE 2.8). Glands in this system secrete hormones, another form of chemical messenger. Hormones travel through our bloodstream and influence many aspects of our life—growth, reproduction, metabolism, and mood.

Figure 2.8: FIGURE 2.8 The endocrine system

Some hormones are chemically identical to neurotransmitters. The endocrine system and nervous system are therefore close relatives. Both produce molecules that act on receptors elsewhere. Like many relatives, they also differ. The speedier nervous system zips messages from eyes to brain to hand in a fraction of a second. Endocrine messages trudge along in the bloodstream, taking several seconds or more to travel from the gland to the target tissue. The nervous system transmits information to specific receptor sites with text-message speed. The endocrine system is more like delivering an old-fashioned letter.

adrenal [ah-DREEN-el] glands a pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress.

But slow and steady sometimes wins the race. The effects of endocrine messages tend to outlast those of neural messages. Have you ever felt angry long after the cause of your angry feelings was resolved (say, your friend apologized for her rudeness)? You may have experienced an “endocrine hangover” from lingering emotion-related hormones. Angry feelings can hang on, even when we’ve chosen to move past them. When this happens, we need a little time to simmer down. Consider what happens behind the scenes when you hear burglar-like noises outside your window. Your ANS may order your adrenal glands to release epinephrine and norepinephrine (also called adrenaline and noradrenaline). In response, your heart rate, blood pressure, and blood sugar will rise, giving you a surge of energy known as the fight-or-flight response. When the “burglar” turns out to be a playful friend, the hormones—and your alert, aroused feelings—will linger a while.

pituitary gland the most influential endocrine gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands.

The endocrine glands’ control center is the pituitary gland. This pea-sized structure, located in the brain’s core, is controlled by a nearby brain area, the hypothalamus (more on that shortly). The pituitary releases a number of hormones. One is a growth hormone that stimulates physical development. Another is oxytocin, which enables contractions during birthing, milk flow in nursing, and orgasm. Oxytocin also promotes social interactions. When couples bond, or when we experience feelings of group togetherness or social trust, oxytocin’s pleasant presence is paving the way (De Dreu et al., 2010; Zak, 2012).

Pituitary secretions also direct other endocrine glands to release their hormones. The pituitary, then, is a master gland (whose own master is the hypothalamus). For example, under the brain’s influence, the pituitary triggers your sex glands to release sex hormones. These in turn influence your brain and behavior.

This feedback system (brain → pituitary → other glands → hormones → body and brain) reveals the interplay between the nervous and endocrine systems. The nervous system directs endocrine secretions, which then affect the nervous system. In charge of this whole electrochemical orchestra is that master conductor we call the brain.

Retrieve + Remember

Question
2.

9

•Why is the pituitary gland called the “master gland”?

ANSWER: Responding to signals from the hypothalamus, the pituitary releases hormones that trigger other endocrine glands to secrete hormones, which in turn influence our brain and our behavior.

Question
2.10

•How are the nervous and endocrine systems alike, and how do they differ?

ANSWER: Both of these communication systems produce chemical molecules that act on the body’s receptors to influence our behavior and emotions. The endocrine system, which secretes hormones into the bloodstream, delivers its messages much more slowly than the speedy nervous system, and the effects of the endocrine system’s messages tend to linger much longer than those of the nervous system.

The endocrine system and how it relates to other organ systems (Proceedings)

During the past 35 years there has been a dramatic emergence of both experimental and clinically applicable information in the subspecialty of endocrinology. With the development of such invaluable laboratory methodologies as radioimmunoassay (RIA), thinlayer chromatography (TLC), enzyme-linked immunosorbent assay (ELISA) and equilibrium dialysis (especially valuable in the measurement of free/unbound circulating hormones (ie., FT4). Hormones such as adrenocorticotropic hormone (ACTH), thyroid stimulating hormone (TSH) and gastrin, whose normal levels in canine and feline plasma/serum are so minute that they are measured in picomoles/milliliter (pmol/ml) can now can now be detected reliably. The development of monoclonal antibodies yields RIA results of incredible accuracy and specificity. Radioisotope imaging, CT and MRI scanning has enabled clinicians to detect various endocrine neoplasms prior to exploratory surgery.

Before the small animal clinician can confidently utilize such sophisticated diagnostic techniques, it is imperative that he or she has a firm understanding of the physiology and pathophysiology of the endocrine system.

Because living things have evolved from single-cell species to complex organisms, a system of organs to integrate the actions of the other organ systems and disseminate physiologic information from one region of the body to another was needed. The endocrine system acts as an overseer to maintain consistent function of all the other body systems. The maintainence of constancy within one’s internal environment is termed HOMESTASIS.

The classic concept of the endocrine (Gr. endo-within; krinein to separate) system is a goup of organs that produce substances termed hormone (Gr. Hormeos I excite), which are secreted directly into the circulation instead of through a ductal system. Hormones are disseminated throughout the body and affect the function of other organs (target organs). Within this classic concept of endocrinology is the basic set of glands which are at its foundation (i.e., the pituitary, the thyroids, the parathyroids, the adrenals, the islets of Langerhands, the ovaries and the testes. The fact that most endocrine glands may continue to function quite adequately, even if transplanted to other regions of body, vividly illustrates the concept of ductless secretion of hormones. An exception to this concept is the pituitary gland, which derives its stimulation from hypothalamic releasing factors.

The latter portion of the 20th century revealed an expansion of our classic concept of the endocrine system. Various cell groups in the alimentary tract produce substances that evoke a hormonal response upon their target organs (the so-called APUD cells, which are embryologically derived form neural crest cells). The kidney functions as an endocrine gland with the secretion of 1, 25, dihroxycholecalciferiol, erythropoietin and rennin. The prostate gland, pancreas uterus and lungs contain ample concentrations of prostaglndins which have profound effects upon smooth muscle function, blood pressure, blood coagulation and the inflammatory process.

Chemically, hormones may be classified by their molecular composition (small peptides, large peptides amino acid derivatives, fatty acid derivatives and steroids). Knowledge of a hormone’s chemical structure enables the clinician to determine the most accurate method to measure it (serum vs. plasma vs. urine; RIA vs. ELISA vs. equilibrium dialysis vs. thin layer chromatography).

Hormones modify cellular metabolic processes directly or indirectly. As a general rule the combination of a hormone with its receptor results in intracellular changes by one of two mechanisms 1) the emergence of a second messenger within the cell; or 2) the translocation of the hormone-receptor complex into the nucleus. Steroid hormones which are lipid soluble, diffuse freelythrough the cell membrane and exert their effects via the second mechanism. Catecholamines and polypeptides appear to affect their target organs via the first mechanism; which activates the intracellular enzyme, adenylate cyclase which reacts with ATP forming Cyclic AMP causing the altered cellular function.

The synthesis and release of a specific hormone must be strictly regulated (i.e. , the endocrine gland must be both suppressible and also have the reserve capacity to secrete increased concentrations of the hormone to fulfill a physiologic need). An important basic principle of hormonal regulation is the negative feedback system This implies that if a supraphysiologic level of a certain hormone is present in the circulation, this will induce suppression of any further secretion of that hormone until its blood level decreases within its normal physiologic range (an example would be excessive levels of cortisol will produce a negative feedback upon the hypothalamus and adenohypophysis; suppressing the further release of CRF and ACTH, respectively

References

Drazner, FH: Small Animal Endocrinology Churchill Livingstone. 1984.

Drazner, FH: A Case Report of a Dog with Gastrinoma, Resembling the Zollinger-Ellison Syndrome. California Veterinarian. 1978.

Mooney, CT. and Peterson ME (eds) BSAVA Manual of Canine and Feline Endocrinology. BSAVA. 2004.

Monroe, WE: Disease of the Endocrine Pancreas and Pituitary Gland in: Leib MS. and Monroe WE. :(eds.) Practical Small Animal Internal Medicine, WB Saunders. 1997.

Endocrine System Information

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Introduction

The endocrine system helps regulate and maintain various body functions by synthesizing (making) and releasing hormones, chemical messengers. The major areas of control and integration include responses to stress and injury, growth and development, absorption of nutrients, energy metabolism, water and electrolyte balance, reproduction, birth, and lactation. The endocrine system is composed of glands that release their hormones directly into the bloodstream for chemical signaling of target cells. These glands include the pituitary gland, the pineal gland, the hypothalamus, the thyroid gland, the parathyroid glands, the thymus, the suprarenal (adrenal) glands, the ovaries (in females) or testes (in males), and the pancreas.

Typically, the body synthesizes hormones in one part and transports it to another through the bloodstream or lymph. Endocrine glands have a rich blood supply through which hormones travel to reach their target organs. Hormones alter the metabolism of target organs by increasing or decreasing their activity. These changes in activity are strictly balanced to maintain homeostasis (a stable internal environment).

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Glands and neural components

Glands are of two types. Endocrine glands do not have a duct system and are called ductless glands. These glands release hormones directly into the blood or lymph. Exocrine glands such as the sudoriferous (sweat) glands contain ducts. Ducts are tubes leading from a gland to its target organ.

The endocrine system and the nervous system are so closely associated that they are collectively called the neuroendocrine system. Neural control centers in the brain control endocrine glands. The main neural control center is the hypothalamus, also known as the “master switchboard.” Suspended from the hypothalamus by a thin stalk is the pituitary gland. The hypothalamus sends messages to the pituitary gland; the pituitary gland, in turn, releases hormones that regulate body functions.

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Homeostatic feedback mechanisms

Many endocrine glands are linked to neural control centers by homeostatic feedback mechanisms. The two types of feedback mechanisms are negative feedback and positive feedback. Negative feedback decreases the deviation from an ideal normal value, and is important in maintaining homeostasis. Most endocrine glands are under the control of negative feedback mechanisms.

Negative feedback mechanisms act like a thermostat in the home. As the temperature rises (deviation from the ideal normal value), the thermostat detects the change and triggers the air-conditioning to turn on and cool the house. Once the temperature reaches its thermostat setting (ideal normal value), the air conditioning turns off.

An example of negative feedback is the regulation of the blood calcium level. The parathyroid glands secrete parathyroid hormone, which regulates the blood calcium amount. If calcium decreases, the parathyroid glands sense the decrease and secrete more parathyroid hormone. The parathyroid hormone stimulates calcium release from the bones and increases the calcium uptake into the bloodstream from the collecting tubules in the kidneys. Conversely, if blood calcium increases too much, the parathyroid glands reduce parathyroid hormone production. Both responses are examples of negative feedback because in both cases the effects are negative (opposite) to the stimulus.

Positive feedback mechanisms control self-perpetuating events that can be out of control and do not require continuous adjustment. In positive feedback mechanisms, the original stimulus is promoted rather than negated. Positive feedback increases the deviation from an ideal normal value. Unlike negative feedback that maintains hormone levels within narrow ranges, positive feedback is rarely used to maintain homeostatic functions.

An example of positive feedback can be found in childbirth. The hormone oxytocin stimulates and enhances labor contractions. As the baby moves toward the vagina (birth canal), pressure receptors within the cervix (muscular outlet of uterus) send messages to the brain to produce oxytocin. Oxytocin travels to the uterus through the bloodstream, stimulating the muscles in the uterine wall to contract stronger (increase of ideal normal value). The contractions intensify and increase until the baby is outside the birth canal. When the stimulus to the pressure receptors ends, oxytocin production stops and labor contractions cease.

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Pituitary gland

The pea-size pituitary gland is called the “master gland” because it regulates many key functions. The pituitary gland has an adenohypophysis (anterior lobe) and a neurohypophysis (posterior lobe). The adenohypophysis produces and secretes seven hormones in response to commands from the hypothalamus:

• Thyroid Stimulating hormone (TSH)
• Adrenocorticotropic hormone (ACTH)
• Follicle Stimulating hormone (FSH)
• Luteinizing hormone (LH)
• Prolactin (PRL)
• Growth hormone (GH)
• Melanocyte-stimulating hormone (MSH)

The TSH, ACTH, FSH, and LH hormones are tropic hormones that simulate other endocrine glands. In response, the other endocrine glands produce hormones that affect metabolism. For example, TSH from the pituitary gland stimulates the thyroid gland to produce thyroid hormones. In turn, thyroid hormones inhibit the release of calcium in the blood.

Other adenohypophysis hormones have unique effects upon metabolism. ACTH acts upon the cortex (outer area) of the suprarenal (adrenal) gland to produce steroid hormones. FSH and LH act upon women and men in regulating various sexual characteristics.

Prolactin and growth hormone act upon certain body tissues; they do not affect specific organs. Prolactin travels to the breast tissue glands of nursing mothers, causing milk production. Growth hormone stimulates protein synthesis and cell division in cartilage and bone tissue. Gigantism results when excessive amounts of growth hormone are produced during childhood. Pituitary dwarfism occurs when too little growth hormone is produced. Acromegaly occurs when too much GH is produced during adulthood.

Neuron cell bodies of the hypothalamus produce two hormones: antidiuretic hormone (ADH) and oxytocin. These hormones are transported along the axons to the axon terminals in the pituitary posterior lobe. Both hormones are stored in the terminals until they are released into the blood vascular network surrounding the posterior pituitary gland.

ADH acts upon the kidney tubules to help maintain a constant level of body water. This level is accomplished by increasing the water reabsorption amount when body water levels are low. Oxytocin triggers milk release from breast tissue when infants nurse and causes muscle contractions in the uterus during labor.

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Thyroid gland

The thyroid gland has two lobes connected by an isthmus (small connecting stalk) and is in the lower part of the neck just below the larynx. The thyroid gland produces three hormones:

• Thyroxine (T4)
• Triiodothyronine (T3)
• Calcitonin

T3 and T4 are collectively called thyroid hormone and are produced in the follicles (hollow spherical structures) of the thyroid gland. Thyroid hormone affects body growth, metabolic rates, and the development of bones and skeletal muscle. Thyroid hormone also increases the sensitivity of the cardiovascular system to sympathetic nervous activity. This effect helps maintain a normal heart rate.

Parafollicular cells (C cells) between the thyroid gland follicles produce calcitonin. Calcitonin lowers blood calcium levels.

The parathyroid glands are embedded in back of the thyroid gland and secrete PTH (parathyroid hormone). PTH increases blood calcium by stimulating bone calcium release into the bloodstream and by increasing the calcium absorption rate in the gastrointestinal tract and kidneys.

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Suprarenal (adrenal) glands

The suprarenal (adrenal) glands are on top of each kidney. Each gland has a cortex (outer region) and a medulla (inner region). The cortex secretes glucocorticoids such as cortisol, mineralocorticoids, and small amounts of androgens and estrogens responsible for some secondary sex characteristics. Glucocorticoids raise blood sugar levels by increasing gluconeogenesis (synthesis of glucose from amino acid). This action ensures glucose supplies for the body when it is under stress. Mineralocorticoids such as aldosterone promote sodium (salt) reabsorption by stimulating the kidneys to absorb more sodium from the blood.

The medulla “emergency gland” develops from nervous tissue; the autonomic nervous system controls its secretions. The medulla secretes epinephrine (adrenaline) and norepinephrine (noradrenaline), chemicals that raise the blood levels of sugar and fatty acids. These hormones also increase the heart rate and force of contraction. These effects prepare the body for the “Fight or Flight” response (instant physical activity), enabling the individual to think quicker, fight harder, and run faster. These hormones also constrict the blood vessels supplying the skin, kidneys, gastrointestinal tract, and other areas of the body not needed for the response.

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Ovaries and testes

The ovary is the site of estrogen and progesterone synthesis. Estrogen is required to form the ovum (egg) during oogenesis and prepares the uterus for implanting a fertilized egg. Progesterone prepares the breasts for lactation during pregnancy and works with estrogen to regulate the menstrual cycle.

The testes produce the hormone testosterone. Testosterone is required for sperm formation during spermatogenesis, the development of male external genitalia, and secondary sexual traits such as beard growth, chest hair, and enlarged thyroid cartilage.

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The Endocrine System: Hypothalamus and Pituitary

Are you hot right now? Cold? Maybe you’re like Goldilocks and are just right. What about your height? Are you tall? Average? Short? Maybe your metabolism is lightning fast and you’re always hungry, or maybe it’s a bit slow and you stay full longer. All of these—regardless of which one you identify with—are regulated by the endocrine system.

What is the endocrine system? It’s a network of glands throughout the body that regulate certain body functions, including body temperature, metabolism, growth, and sexual development.

Want to learn more about glands and hormones? Check out our free Endocrine System eBook!

Though there are many glands, today we’ll focus on just two: the hypothalamus and the pituitary gland.

Image from Human Anatomy Atlas.

I’m going to be throwing a lot of information at you, dear reader, so brace yourself!

Hormone Reaction Regulation

It’s no secret your brain is one busy place—neurons move at incredible speeds, synapses are constantly firing, blood is pumping, and glands are producing hormones. These glands, specifically the hypothalamus and pituitary, are working all the time to keep your body running at optimal performance. Every hormone the endocrine system releases follows a basic set-up: a signal is received, hormones are secreted, and the target cell undergoes changes to its basic functions.

Hypothalamus

The almond-sized hypothalamus is located below the thalamus and sits just above the brainstem. All vertebrate brains have a hypothalamus. Its primary function is to maintain homeostasis (stability of the internal environment) in the body.

Image from Human Anatomy Atlas.

The hypothalamus links the nervous and endocrine systems by way of the pituitary gland. Its function is to secrete releasing hormones and inhibiting hormones that stimulate or inhibit (like their names imply) production of hormones in the anterior pituitary. Specialized neuron clusters called neurosecretory cells in the hypothalamus produce the hormones Antidiuretic Hormone (ADH) and Oxytocin (OXT), and transport them to the pituitary, where they’re stored for later release.

Think of the hypothalamus as the pituitary’s older sibling—it not only controls the actions of the pituitary but it secretes at least nine hormones to the pituitary’s seven.

Pituitary Gland

Attached to the hypothalamus, the pituitary gland is a pea-sized, reddish-gray body that stores hormones from the hypothalamus and releases them into the bloodstream. The pituitary consists of an anterior lobe and a posterior lobe, each of which have distinct functions.

Image from Human Anatomy Atlas.

Pituitary: Anterior Lobe (Adenohypophysis)

The anterior lobe (or adenophyophosis) secretes hormones that regulate a wide variety of bodily functions. There are five anterior pituitary cells that secrete seven hormones:

This table represents the types of hormones secreted by the cells of the anterior pituitary.

Pituitary: Posterior Lobe (Neurohypophysis)

While the anterior lobe shoulders most of the work in producing hormones, the posterior lobe stores and releases only two: oxytocin and antidiuretic hormone (ADH), or vasopressin.

Pituitary Disorders

Even though it’s very small, the pituitary gland isn’t free from ailment—nothing is completely foolproof, after all.

Most disorders of the pituitary glands are tumors, which are common in adults. These growths are not  considered brain tumors, nor are they always malignant. In fact, they’re almost always benign in nature! There are two types of pituitary tumors—secretory and non-secretory. A secretory tumor produces too much of a hormone, while a non-secretory tumor does not. Regardless, if the tumor is big enough, it can hinder normal pituitary function. These tumors can be removed, or monitored and controlled with medication.

Problems caused by tumors fall into certain categories:

• Hyposecretion: Too little of a hormone is produced, interfering in normal function.

• Hypersecretion: Too much of a hormone is produced, interfering in normal function.

• Mass effects: The tumor presses on the pituitary or other areas of the brain, causing pain, vision issues, or other problems.

While the pituitary and hypothalamus can run into the above issues, on the whole they work a balancing act on your body. So the next time you’re feeling juuuust right, you can thank the pituitary, hypothalamus, and all the other organs of the endocrine system.

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Endocrine system Facts for Kids

The endocrine system includes those organs of the body which produce hormones. It helps to regulate metabolism, growth and development, tissue function, and plays a part also in mood. The field of medicine that deals with disorders of endocrine glands is endocrinology.

In physiology, the endocrine system is a system of glands, each of which secretes a type of hormone directly into the bloodstream to regulate the body.

The endocrine system is in contrast to the exocrine system, which secretes its chemicals using ducts. The endocrine system is an information signal system like the nervous system, yet its effects and mechanism are different.

The endocrine system’s effects are slow to start, and long-lasting in their response. The nervous system sends information quickly, and responses are generally short lived. Hormones are complex chemicals released from endocrine tissue into the bloodstream where they travel to target tissues and trigger a response.

Features of endocrine glands are, in general, they have no ducts, they have a good blood supply, and usually they have vacuoles or granules inside their cells, storing their hormones.

Endocrine glands and the hormones they secrete

Central nervous system

Endocrine glands in the human head and neck and their hormones

• Hypothalamus produces
  • Thyrotropin-releasing hormone (TRH) Parvocellular neurosecretory neurons
  • Gonadotropin-releasing hormone (GnRH) Neuroendocine cells of the Preoptic area
  • Growth hormone-releasing hormone (GHRH) Neuroendocrine neurons of the Arcuate nucleus
  • Corticotropin-releasing hormone (CRH) Parvocellular neurosecretory neurons
  • Vasopressin Parvocellular neurosecretory neurons
  • Somatostatin (SS; also GHIH, growth hormone-inhibiting hormone) Neuroendocrince cells of the Periventricular nucleus
  • Prolactin inhibiting hormone or PIH or Dopamine (DA) Dopamine neurons of the arcuate nucleus
  • Prolactin releasing hormone

• Pituitary gland (hypophysis) produces
  • Anterior pituitary lobe (adenohypophysis)
    • Growth hormone (GH) Somatotropes
    • Prolactin (PRL) Lactotropes
    • Adrenocorticotropic hormone (ACTH, corticotropin) Corticotropes
    • Lipotropin Corticotropes
    • Thyroid-stimulating hormone (TSH, thyrotropin) Thyrotropes
    • Follicle-stimulating hormone (FSH) Gonadotropes
    • Luteinizing hormone (LH) Gonadotropes
  • Posterior pituitary lobe (neurohypophysis)
    • Oxytocin Magnocellular neurosecretory cells
    • Vasopressin (AVP; also ADH, antidiuretic hormone) Magnocellular neurosecretory cells
  • Intermediate pituitary lobe (pars intermedia)
    • Melanocyte-stimulating hormone (MSH) Melanotroph

Thyroid

• Thyroid produces
  • Triiodothyronine (T3), the potent form of thyroid hormone Thyroid epithelial cell
  • Thyroxine (T4), also known as tetraiodothyronine: it is a less active form of thyroid hormone (mainly) Thyroid epithelial cells
  • Calcitonin Parafollicular cells

Alimentary system

• Stomach produces
  • Gastrin (mainly) G cells
  • Ghrelin P/D1 cells
  • Neuropeptide Y (NPY)
  • Secretin S cells
  • Somatostatin D cells
  • Histamine ECL cells
  • Endothelin X cells

• Liver produces
  • Insulin-like growth factor (IGF) (mainly) Hepatocytes
  • Angiotensinogen Hepatocytes
  • Thrombopoietin Hepatocytes

• Pancreas produces
  • Insulin (mainly) β Islet cells
  • Glucagon (also mainly) α Islet cells
  • Somatostatin δ Islet cells
  • Pancreatic polypeptide PP cells

Kidney

• Kidney produces
  • Renin (Primarily) Juxtaglomerular cells
  • Erythropoietin (EPO) Extraglomerular mesangial cells
  • Calcitriol (the active form of vitamin D₃)
  • Thrombopoietin

Adrenal glands

• Adrenal glands
  • Adrenal cortex produces
  • Adrenal medulla produces
    • Adrenaline (epinephrine) (Primarily) Chromaffin cells
    • Noradrenaline (norepinephrine) Chromaffin cells
    • Dopamine Chromaffin cells
    • Enkephalin Chromaffin cells

Reproductive system

Male

Female

Calcium regulation

Miscellaneous

Other pages

90,000 Endocrine system. Norm and pathology

Endocrine system as a natural phenomenon

The endocrine system, it is also the system of neurohumoral regulation (literally “nerve-fluid control”), is extremely complex. Its structure, composition and functioning are, apparently, at the limit of what, in principle, can be investigated and comprehended by modern science, armed with a powerful (as it seems to it) instrumental, laboratory-analytical and computational arsenal.A whole branch of medicine, called endocrinology, deals with the study of this system, its normal operation, its various dysfunctions and diseases, as well as methods of treating the latter. An entire sector of pharmacology is engaged in the development, synthesis and improvement of the so-called. hormone-containing drugs; despite the chronic problem of side effects, it is no longer possible to do without this group of drugs.

Organs (glands), tissues or cells of a certain type related to the endocrine system, for example, Kulchitsky’s cells in the intestinal mucosa, produce special organic compounds that are usually called bioactive regulators, neurotransmitters, signaling biochemical substances, but more often just hormones. This word is translated from Greek means “to excite”, “to induce” or, in more modern language, “to activate”. Hormones go directly into the bloodstream; the slightest fluctuations in their concentration in living tissues are captured by specific receptor cells that are sensitive to one or another group of hormones and are able to respond to hormonal “commands” – for example, an increase in body temperature, a decrease in blood pressure in blood vessels, intense lactogenesis in the mammary glands, and many .other. In this way, practically all physiological and mental processes in the body are triggered, forced, inhibited or completely suppressed – in a word, controlled.In this case, each gland, as a rule, secretes several hormones, and each hormone, in turn, affects several interrelated processes.

The synonymous term “neurohumoral regulation” does not accidentally contain the root “neuro-“. According to modern concepts, the endocrine system plays an important, exclusive role in the vital activity of the organism, but nevertheless it is not the “supreme power” in relation to it. Hierarchical primacy belongs to the central nervous system (CNS), i.e.e. to the brain and spinal cord. Hormones are responsible for everything, but the secretory activity of the endocrine glands themselves is controlled by special cerebral formations and appendages, – first of all, the hypothalamus-pituitary ligament in the lower region of the brain, in the so-called. diencephalon – using for this signal electrochemical impulses and a whole web of neural communication channels (in IT, such an internal network would be called an intranet). Given the above, endocrinology today is increasingly identified with neuroendocrinology (which was considered a separate field half a century ago), and a group of disorders previously traditionally called hormonal are interpreted as neuroendocrine diseases or dysfunctions.

It is difficult to say why the evolving mammals developed such a complex, multistage and multielement neuroendocrine system. As you know, nature cares most about expediency, and least of all about making it convenient for a person to study it. Nature always has a lot of possible ways and options; most likely, infinitely many. It would certainly be possible to regulate the vital activity of higher organisms in some other way, and preferably simpler. However, the following cannot be denied.A modern, reasonable and technological man is still very far from creating an artificial system similar to himself – a system as compact, energetically economical and efficient, with five autonomous sensor units and two universal manipulators at once; a system that optimally combines strength, flexibility and mobility, unconditioned and conditioned reflexes, consciousness and unconsciousness; in addition, the system is self-reproducing, to some extent self-learning and, most importantly, preserving homeostasis (constancy of internal conditions), i.e.That is, self-adjusting for almost any external conditions. Therefore, today we can only admire, thank nature for our amazing endocrine system – and continue to persistently explore its countless mysteries.

Main endocrine glands

You can often find the expression “the main endocrine gland”, and in different sources this role is assigned to the pituitary gland, then the hypothalamus. No one knows what discoveries will be made tomorrow, so we restrict ourselves to a careful repetition of the above: as far as we know today, the activity of the neuroendocrine system (at least most of the endocrine glands) is controlled by a pair of hypothalamus-pituitary gland.In addition, the most important functions of the pituitary gland include the production of growth hormone, which regulates the processes of growth and formation of the body.

Pineal gland (pineal gland of the brain)

is one of the central neuroendocrine regulators. It is a kind of brake or limiter that blocks the excessive “acceleration” of the endocrine glands. In particular, it normalizes the secretion of growth hormone and sex hormones, and prevents tumor processes.

Thyroid is involved in the regulation of metabolism, primarily the assimilation of iodine and calcium; affects many dependent systems and processes (from general energy exchange and intellectual productivity to tissue regeneration of the musculoskeletal system).

Parathyroid (parathyroid) glands regulate the state of bone and muscle tissues, intraocular structures, kidneys.

The adrenal glands produce, according to modern data, about fifty signaling substances. The most famous and studied functions are the provision of water-salt, carbohydrate, mineral, protein metabolism, the production of male and female sex hormones (along with the gonads). The famous glucocorticosteroid hormones produced by the adrenal cortex are not, of course, a panacea and can lead to numerous undesirable effects (especially when taken orally), but they often turn out to be the only “lifeline” due to their pronounced anti-inflammatory, anti-allergic, immunomodulatory, anti-shock and anti-shock and anti-shock and anti-shock effects.No less well-known are such bioregulators as adrenaline and norepinephrine (catecholamine hormones produced by the adrenal medulla).

Paraganglia

are special clusters of cells that can rightfully be called neuroendocrine: they are responsible for sensitivity, regulate chromium metabolism and simultaneously secrete catecholamines, like the adrenal glands.

The pancreas functionally belongs to the digestive system, but contains an insignificant (1-3% of the mass of the gland) volume of endocrine cells, which are concentrated, incl.n. islets of Langerhans and producing insulin – a hormone regulating blood glucose levels.

Testicles (in men), ovaries (in women) – secrete sex hormones (androgens and estrogens). The placenta also plays an endocrine role during gestation.

The thymus gland (thymus) produces mainly immunoregulatory hormones.

It should be noted that by now far from all the functions of the endocrine glands and the hormones produced by them are known; only the most important and explored ones are listed here.

Most common endocrine diseases

The number of independent diseases and syndromes associated with hormonal imbalance is today estimated at about six thousand. In other words, most of the diseases known to modern medicine (about ten thousand) are indeed hormonal. Some of them today threaten to become pandemic, others are sporadically rare; some are congenital and genetically determined, others are acquired during life under the influence of numerous etiopathogenetic factors (trauma, tumors, inflammation, etc.)etc.).

The most common and well-known endocrine-metabolic disease should, apparently, be considered diabetes mellitus. Thyroid pathology is also very common, in particular, endemic iodine deficiency states, hyperthyroidism, thyroiditis, and many others. etc. A pronounced negative effect on the entire body, its formation, structure, appearance, functioning, – have anomalies and lesions of the glands that produce sex hormones, corticoids, somatotropin. Even the well-known premenstrual syndrome in women is nothing more than a transient, cyclical and transient hormonal imbalance.

In general, endocrinology has to think truly globally and systemically, dealing with a huge number of cross-linked processes, normal and pathological. However, the diseases of this group, which were once completely incomprehensible, are now being successfully diagnosed and treated. It is only important to consult a doctor on time – that is, as early as possible – until the changes become irreversible.

90,000 Endocrine causes of obesity | Useful information from VESNA Clinic

Obesity and overweight can develop for various reasons.As we wrote in the previous article, obesity is primary and secondary. Primary occurs due to an imbalance of received and consumed energy, and this type is diagnosed in 95% of cases. The remaining 5% account for various diseases, which can result in overweight and secondary obesity.

These diseases include some genetic syndromes, cerebral obesity and various disorders of the endocrine system. The latter are called endocrinopathies, and we will talk about them in more detail in this material.

1. Hypothyroidism

Dysfunction of the thyroid gland, in which there is a decrease in the secretion of thyroid hormones. It should be noted that this condition leads to a fairly moderate increase in body weight (within 3-5 kg) and other symptoms come to the fore (general weakness, fatigue, decreased concentration, apathy, dry skin, swelling, tendency to constipation, chilliness).

2. Hyperprolactinemia

A condition in which there is an increase in the secretion of the hormone prolactin.

Prolactin is secreted by the pituitary gland, a gland located in the Turkish saddle. This hormone can increase for various reasons, including as a result of its overproduction by a pituitary adenoma – prolactinoma.

In this case, the mechanism of body weight gain is associated with the effect of an increased level of prolactin on sex hormones and its direct effect on adipose tissue.

3. Hypercortisolism

The disease develops due to increased production of the hormone cortisol by the adrenal cortex.In this disease, a redistribution of subcutaneous fat occurs with a predominant deposition of fat in the upper body, while the legs can remain thin.

4. Hypogonadism Decreased levels of sex hormones.

This condition can be both the cause of overweight, and its consequence.

In women, various menstrual irregularities come to the fore, up to amenorrhea (absence of menstruation), climacteric syndrome, decreased sex drive.In men, complaints of decreased libido and potency, erectile dysfunction, and decreased muscle strength prevail. With a reduced level of sex steroids, fat metabolism slows down and fat is deposited in the subcutaneous fat.

Conversely, in men, hypogonadism can be a consequence of overweight: against the background of obesity, due to the excessive conversion of testosterone to estradiol in adipose tissue cells, testosterone levels decrease under the action of the aromatase enzyme, and male hypogonadism develops.

Balance of hormones in the female body

How it happens

Hormones are chemicals that help different parts of our body exchange information. Special endocrine glands and individual cells located in various places – for example, on the walls of the stomach or (horror!), In the subcutaneous fatty tissue, secrete hormones into the blood, and other organs and tissues capture the information transmitted in this way.

Basic female hormones

It just so happens that women are considered more hormone dependent than men.This is nonsense from the point of view of biology, but such an opinion has appeared for two objective reasons. Firstly, the monthly cycle regulated by hormones (fluctuations in mood and well-being of men are not so predictable). Secondly, it often depends on the state of the endocrine system whether a woman will be able to get pregnant and give birth to a child, and this is considered by many as the main female function.

The main female hormones (although they are produced in small quantities in the male body) are estrogens and progesterone.

Estrogens – a group of hormones that are constantly produced by the ovaries from the beginning of puberty until the onset of menopause. In different phases of the menstrual cycle, the amount of estrogen is different. They regulate the menstrual cycle, and in addition, they protect blood vessels from the formation of cholesterol plaques on the walls, regulate water-salt metabolism, increase skin elasticity, regulate the activity of the sebaceous glands (which is why a sign of a healthy woman in her prime is radiant, moist skin).

These hormones are also responsible for the strength of bones: they stimulate the formation of new bone tissue, retaining the necessary substances in it – calcium and phosphorus. Therefore, in menopause, when the level of estrogen in the body decreases, women often have fractures or the development of osteoporosis.

Progestins (progesterone) in the female body perform many functions – from the formation of mammary glands in girls to ensuring the possibility of the onset and maintenance of pregnancy. Soreness of menstruation and many manifestations of premenstrual syndrome are associated with progestin deficiency.

These hormones are closely interconnected with each other, as well as with other hormones. To understand this requires special education. That is why only doctors can make an accurate diagnosis and prescribe hormonal drugs, and self-medication, even with herbs, is extremely dangerous. You won’t knock on your great-grandmother’s mechanical watch if it starts to junk? And the endocrine system is even more complex and thinner than an antique clockwork.

See your doctor if:

• You experience frequent mood swings and irritability.
• Problems with sleep during the premenstrual and menstrual periods.

These signs may indicate an imbalance in the balance of estrogen and progestins. A qualified gynecologist or endocrinologist, gynecologist-endocrinologist will help you to normalize your condition and prevent possible health problems.

What happens if the balance is out of order:

Diseases of the endocrine system develop due to either insufficient or excessive production of hormones.

Hormones are a connecting link between various systems of the body, therefore, disruptions in the endocrine system can affect several organs and systems at the same time. Remember that with timely access to an endocrinologist, treatment will be most effective.

Some specific problems can be identified, in the event of which you should immediately contact a specialist.

a. Reproduction problems

Almost all hormones produced in the endocrine organs affect sexual function.Hormone-active tumors of the pituitary gland, pathology of the thyroid gland and adrenal glands, various inflammatory diseases of the endocrine system, etc. can lead to infertility. For the timely detection of these serious diseases, all patients suffering from reproductive disorders (infertility, miscarriage) must must be examined by an endocrinologist.

Menstrual irregularities can also be associated with functional disorders of the endocrine glands.These disorders respond well to treatment if detected early.

Many women seeking help for menstrual irregularities suffer from what is known as polycystic ovary syndrome. The main symptoms of the syndrome are increased hair growth on the face, abdomen, chest, and the appearance of acne. Treatment is carried out jointly by an endocrinologist and a gynecologist.

In this disease, the ovarian capsule thickens, the formation of female sex hormones is disrupted.The cause of these disorders can be both an enzymatic defect in the ovaries or adrenal glands, and dysfunction of the hypothalamic-pituitary system. As a result, the content of male sex hormones in a woman’s body increases, the menstrual cycle is disrupted, and, as a result, infertility.

b. Weight fluctuations

Both obesity and unreasonable weight loss can be the result of severe endocrine diseases (diffuse toxic goiter, adrenal insufficiency, diabetes mellitus).Even in the absence of serious diseases, with a pronounced deficit of body weight, a deficiency of sex hormones may occur, since a certain proportion of female sex hormones are produced in the subcutaneous fatty tissue.

Well, an excess of adipose tissue (excess! A certain amount of fat in the body is the norm!) Is not only an aesthetic problem. The more adipose tissue, the lower the amount of estrogen and their activity.

Therefore, with obesity, violations of the woman’s reproductive function are also detected, the number of ovulations decreases, changes in the endometrium occur (with the risk of developing cancer of the endometrium, ovaries, mammary glands, spontaneous abortion, complicated by the course of pregnancy and childbirth).

That is why the main stage in the treatment of reproductive disorders for obese women is to reduce body weight, while the hormonal profile of obese women changes, the menstrual cycle is restored in 80%, the frequency of pregnancies increases by about 29%.

SM-Clinic has developed special programs for the treatment of menstrual irregularities, polycystic ovary syndrome, infertility in obese women. The program for reducing body weight includes a reduction diet, exercise, as well as drug therapy for obesity.The achieved result is usually sufficient to restore menstrual dysfunction, even without additional hormonal therapy. It is carried out in the second stage, if recovery has not occurred.

c. Diabetes mellitus

One of the very complex and serious diseases of the endocrine system is diabetes mellitus. Women with this disease may have problems carrying a pregnancy. Therefore, when planning pregnancy and the entire period of its course, a woman suffering from diabetes should be under constant supervision of an endocrinologist and gynecologist.

d. Endocrine disorders of the climacteric period

Menopause (cessation of menstruation) is only one of a number of anatomical, physiological and psychological changes related to the climacteric period. This transition usually takes a decade (45-55 years). The climacteric period is accompanied by many subjective and objective symptoms and metabolic changes, the main cause of which is a significant decrease in estrogen levels.
The climacteric syndrome is usually accompanied by “hot flashes” (exhausting women), bad mood and well-being, increased blood pressure, etc.
When menopause occurs, it is necessary to see a gynecologist every six months. A specialist can help reduce all the anxiety associated with physiological changes in the body.

Endocrinologists and gynecologists “SM-Clinic” have been successfully correcting hormonal disorders in women of any age for more than 5 years.

You can find out more details and sign up for a specialist consultation by calling +7 (495) 292-39-72

Useful articles on the website of the laboratory Litech

Tests for reproductive hormones must be passed to spouses who have not been able to conceive a child for more than a year. Hormonal disorders are one of the most common causes of infertility in women and men. Today, most of the pathologies of the endocrine system are treatable. In order for the doctor to choose for you an individual therapy that normalizes the level of reproductive hormones, you must undergo a comprehensive examination.

Male sex hormones

A man’s reproductive function directly depends on the work of the endocrine system. So, with a decrease in testosterone levels, the number of live and active sperm in the ejaculate significantly decreases. Among the external signs of impaired reproductive function in men:

• female pattern gain,
• lack of facial and body hair,
• decreased sex drive.

If such symptoms appear, you need to be tested for:

• testosterone,
• prolactin,
• FSG,
• TTG,
• LH,
• PSA general and free,
• SHNG,
• leptin.

The state of the hormonal background is significantly influenced by physical and emotional stress. For 2-3 days before the blood test, you need to stop exercising, sexual intercourse, hot baths and saunas. Alcohol, medications, some diagnostic procedures – X-rays, colonoscopy, etc. – can distort the results a few days before the test. You can check the full preparation rules with the attending physician or administrators of our laboratory

Hormones of reproduction in women

Women suspected of infertility are tested for the following reproductive hormones:

• estradiol,
• progesterone,
• DEA sulfate,
• testosterone,
• TTG,
• T3,
• T4,
• prolactin,
• LH,
• free estriol,
• androstenedione,
• AMG.

The level of reproductive hormones in a woman’s body changes depending on the phase of the cycle. Only your gynecologist can determine the exact day of the examination. Patients with amenorrhea or irregular periods need to be tested several times.

It is not recommended to take an analysis for reproductive hormones while taking medications, immediately after interventions, injuries and severe stress. The general rules for preparing for tests are the same as for men. Please note: Breast stimulation can increase the production of certain sex hormones, in particular prolactin.If you have been examined by a mammologist, it is better to postpone hormonal tests for several days.

To study hormonal levels, men and women donate blood from a vein. As a rule, one procedure is sufficient for a comprehensive fertility test. You can sign up for a blood test through the form on the website.

All articles

An important UN report examines the effects of human exposure to chemicals that destroy hormones

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According to the State of the Science of Endocrine Disrupting Chemicals, a new report by the United Nations Environment Program (UNEP) and the World Health Organization (WHO), many Synthetic chemicals that have not been studied as harmful to the hormonal system can have significant health effects.

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“More research is urgently needed to gain a better understanding of the health and environmental impact of endocrine disruptors.”

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\ nDr. Maria Neira, Director, WHO Department of Public Health and Environment \ n

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\ nThe joint study calls for more research to better understand the links between endocrine disrupting chemicals system (EDC), which are found in many household chemicals and industrial products, and certain diseases and disorders.The report notes that more comprehensive assessments and better testing methods will reduce potential disease risks and save significant public health costs.

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Certain substances can alter the function of the hormonal system

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\ nHuman health depends on a well-functioning endocrine system that regulates the release of certain hormones that are essential for functions such as metabolism, growth and development, sleep and mood.Certain substances known as endocrine disruptors can alter the function / function of the hormonal system, increasing the risk of adverse health effects. Some EDCs occur naturally, while synthetic varieties can be found in pesticides, electronic devices, personal care products, and cosmetics. They can also be found as additives or contaminants in foods.

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\ nThis UN study, the most comprehensive report on EDCs to date, highlights some of the links between EDC exposure and health problems, including the potential effects of such chemicals on undescended testicles in boys, breast cancer in women, prostate cancer in men, neurodevelopmental consequences in boys, attention deficit / hyperactivity disorder in children, and thyroid cancer.

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Different ways of human exposure

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\ nHVRES can enter the environment, mainly from industrial and municipal waste, agricultural waste and during the incineration and disposal of garbage. A person can be exposed through the consumption of food, dust and water, inhalation of gases and the smallest particles in the air, and if these substances come into contact with the skin.

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\ n “Chemicals are increasingly used in modern life and are an important part of the national economies of many countries, but the mismanagement of chemicals threatens the achievement of key development goals and sustainable development for all,” said Deputy General UN Secretary-General and UNEP Executive Director Achim Steiner.

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\ n “Investing in new testing methods and research can help to better understand the costs of EDC exposure and reduce risks, while helping to maximize the benefits and offering smarter options and alternatives that are consistent with the transition to green economy, ”added Mr. Steiner.

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More research is needed

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\ nIn addition to exposure to chemicals, other environmental and non-genetic factors such as age and nutrition may be responsible for the observed increase in the number of diseases and disorders.But because of the large gaps in knowledge, it is extremely difficult to determine the exact causes and consequences.

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\ n “More research is urgently needed to gain a better understanding of the health and environmental impact of endocrine disruptors,” said Dr. Maria Neira, Director of Public Health and the Environment, WHO. – The latest scientific evidence shows that communities around the world are exposed to EDCs and their associated risks.WHO will work with partners to prioritize research to explore the links between EDCs and health outcomes in order to mitigate risks. The responsibility to protect future generations lies with all of us. ”

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\ nThe report also notes that similar concerns are caused by the impact of EDCs on wildlife. In Alaska in the United States of America, exposure to such chemicals in some deer populations can lead to reproductive harm, infertility and deformation of the horns.The declining populations of otters and sea lions may also be due in part to their exposure to various PCB compounds, the insecticide DDT, other persistent organic pollutants, and metals such as mercury. At the same time, bans and restrictions on the use of EDCs are associated with the restoration of populations of wild animals and a decrease in health problems.

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Recommendations

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\ nThe study provides a number of recommendations for improving global knowledge of these chemicals, reducing the potential risks of disease and reducing the associated costs.These guidelines include the following:

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• Testing: Known EDCs are just the tip of the iceberg and deeper testing is needed to identify other possible endocrine disruptors, their sources and routes of exposure.

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• Scientific Research: More scientific evidence is needed to determine the effects of the increasingly significant exposure to ECDE mixtures (mainly from industrial waste) on humans and wildlife.

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• Reporting: Many sources of EDCs are unknown due to insufficient reporting and information on the chemicals contained in products, materials and goods.

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• Collaboration: Enhanced data sharing between scientists and between countries can help fill data gaps, mainly in developing and emerging economies.

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\ n “Over the past ten years, great advances have been made in scientific research, showing that endocrine disorders are much more common and more complex than it was thought a decade ago,” said Ake Bergman, professor Stockholm University and editor-in-chief of the report.“As science develops further, it is necessary to ensure both the management of endocrine disrupting chemicals and further research into the effects of these chemicals on wildlife and humans and the consequences of such exposure.”

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For more information please contact:

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\ nNick Nuttall
\ nPress Secretary and Director of Communications UNEP
\ nTel .: +41 79 596 5737 / +254 733 632 755
\ n mail: [email protected]

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\ nGlenn Thomas
\ nLiaison Officer, Communications Department, WHO,
\ nTel: +41 22 791 3983
\ nMobile: +41 79 509 0677
\ n mail: [email protected]

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\ nNada Osseiran
\ nLiaison Officer, Public Health & Environment
\ nTel: +41 22 791 4475
\ nMobile: +41 79 445 1624 90 106 \ n mail: [email protected]

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90,000 Gynecological manifestations of endocrine pathology

Gynecological manifestations of endocrine pathology

Diseases of the endocrine system are diverse both in the localization of the lesion and in their manifestations. The organs of internal secretion produce hormones that regulate the growth, development and functioning of all organs and systems of our complex organism. Gynecological endocrinology is a large branch of medicine dealing with the problems of hormonal regulation of the female reproductive system, and a gynecologist-endocrinologist is a highly qualified specialist who deeply understands the mechanism of action of each hormone and their delicate interaction in the field of women’s health.

What diseases can a gynecologist-endocrinologist treat?

A specialist in gynecological endocrinology diagnoses and treats the following diseases:

1. Infertility resulting from hormonal imbalance.
2. Violation of the menstrual cycle.
3. Hirsutism.
4. Polycystic ovary syndrome.
5. Certain types of acne.
6. Severe premenstrual syndrome.
7. Pathological manifestations of menopause.

In addition, a gynecologist-endocrinologist consults women during pregnancy, prescribes supportive therapy for normal menopause, selects hormonal contraceptives, taking into account the characteristics of a woman’s hormonal status.

Diagnostics and treatment of endocrinological diseases of the female genital area

Reception of a specialist in gynecological endocrinology differs from the usual consultation in duration: in order to make an accurate diagnosis, the doctor must assess the function of almost every system of the woman’s body.The specialist interviews the woman in detail, collects anamnesis, including family history, clarifies complaints, draws attention to the patient’s mental state. The examination is not limited to a standard gynecological examination in a chair: for diagnosis, the doctor must assess the physique, the condition of the skin, the thyroid gland, the parameters of the heart, vascular tone, the condition of the hair, nails and other organs and systems of the body.
After the initial examination, the doctor draws up an individual examination plan, which may include:

• general analysis of blood and urine;
• blood glucose;
• study of hormonal status;
• functional tests;
• ultrasound examination;
• densitometry;
• X-ray examination;
• CT and MRI;
• genetic tests.

Treatment of endocrine and gynecological diseases can be conservative and operative. In the first case, the emphasis is on medical correction of hormonal imbalance, while patients should not be afraid to take hormonal drugs: well-chosen therapy normalizes the work of all organs, improves mental state and prevents the development of complications. In the second case, individual surgical treatment.

You can make an appointment with a gynecologist-endocrinologist of the Medius family medicine clinic network on the website or by calling +7 (812) 777-34-03.

90,000 Assistance to patients with endocrine system problems at KMV

Mood, emotions, general vitality of a person are controlled by hormones. It is the hormonal background that dictates to us the state of mind and body. A malfunction of the thyroid gland can result in both emotional and physical disruptions of the whole organism. Diseases caused by dysfunction of the endocrine glands are becoming more and more, and every tenth inhabitant of our country suffers from this to one degree or another.

In the region of Caucasian Mineral Waters, such patients are treated in the endocrinology department of the city clinical hospital of Pyatigorsk – the only one at the KMV.

The department was founded in 1976. Today it is headed by Tamara Emmanuilovna Butkova, an endocrinologist of the highest category, who has been in the profession for more than forty years. Her hands in the department created comfort and coziness, which are especially important for patients who come here regularly.

The specialists of the department are always aware of new effective methods of diagnosis and treatment of endocrine diseases.

In the case of an endocrine disease requiring surgical treatment, an endocrinologist surgeon is consulted with the choice of the most effective treatment tactics. In addition, consultations of patients with endocrine pathology are carried out by highly qualified cardiologists, neurologists, and ophthalmologists, which makes it possible to diagnose macro- and microvascular complications of diabetes mellitus in a timely manner and to carry out appropriate treatment at the optimal time. Using modern techniques for the study of blood vessels: rheovasography and rheoencephalography, the degree of severity of vascular changes is maximally specified in the endocrinology department.

Endocrinologists widely use modern effective diagnostic methods for endocrine diseases: conducting a glycemic profile, examining glycated hemoglobin, examining thyroid hormones, ultrasound examination of the thyroid gland, fine needle biopsy of thyroid nodules, determining the level of calcium and phosphorus in the blood, X-ray diagnostics.