Discover the profound impact of the endocrine system on our overall health and well-being. Explore the key glands, their functions, and how to maintain optimal endocrine balance.

The Endocrine System: The Unseen Orchestrator of Our Health

The endocrine system is a complex network of glands and hormones that play a vital role in regulating various physiological processes within the human body. While it may not be a common topic of dinner table discussion, understanding the intricacies of this system can have a profound impact on our overall well-being.

The Key Glands of the Endocrine System

The endocrine system is composed of several key glands, each with its own specific functions and responsibilities. These include the hypothalamus, pituitary, thyroid, parathyroid, adrenal, pancreas, ovaries, and testes. Collectively, these glands work in harmony to maintain the delicate balance of hormones that are essential for the proper functioning of the body.

The Intricate Dance of Hormones

Hormones are the chemical messengers produced by the endocrine glands, and they are responsible for a wide range of physiological processes, including growth, metabolism, sexual function, and mood regulation. When the production or distribution of these hormones becomes imbalanced, it can lead to a host of health issues, ranging from fatigue and weight fluctuations to mood swings and reproductive problems.

The Endocrine System’s Influence on Mental and Emotional Well-being

The endocrine system not only affects our physical health but also plays a critical role in our mental and emotional well-being. The hormones produced by the endocrine glands can have a profound impact on our mood, cognitive function, and overall emotional stability. Understanding this connection can help us better manage stress, improve our mental clarity, and enhance our overall quality of life.

Nurturing the Endocrine System for Optimal Health

Maintaining the optimal functioning of the endocrine system requires a holistic approach that incorporates a healthy lifestyle, stress management techniques, and targeted nutritional support. By understanding the unique needs of each endocrine gland and implementing simple, yet effective, strategies, individuals can take an active role in supporting their own endocrine health and well-being.

The Endocrine System and Traditional Chinese Medicine

In Traditional Chinese Medicine (TCM), the endocrine system is closely tied to the internal balance of Yin and Yang energies within the body. Imbalances in these energies can lead to various endocrine disorders, and TCM practitioners use a range of modalities, such as acupuncture and herbal remedies, to help restore this essential balance.

Empowering Ourselves through Endocrine Awareness

By understanding the critical role the endocrine system plays in our overall health and well-being, we can take proactive steps to support its optimal functioning. From adopting healthy lifestyle habits to seeking professional guidance when necessary, individuals can empower themselves to achieve greater balance, vitality, and resilience in the face of the modern world’s challenges.

What are the key glands that make up the endocrine system?

The key glands that make up the endocrine system include the hypothalamus, pituitary, thyroid, parathyroid, adrenal, pancreas, ovaries, and testes. These glands work in harmony to produce and regulate the hormones that are essential for various physiological processes in the body.

How do hormones influence our mental and emotional well-being?

Hormones produced by the endocrine glands can have a significant impact on our mood, cognitive function, and overall emotional stability. Imbalances in these hormones can contribute to a range of mental and emotional health issues, such as depression, anxiety, and mood swings. Understanding the connection between the endocrine system and our mental well-being can help us better manage stress and improve our overall quality of life.

What are some strategies for nurturing the endocrine system for optimal health?

Maintaining the optimal functioning of the endocrine system requires a holistic approach that includes a healthy lifestyle, stress management techniques, and targeted nutritional support. This may involve adopting dietary changes, engaging in regular exercise, practicing relaxation techniques, and seeking guidance from healthcare professionals when necessary.

How does Traditional Chinese Medicine view the endocrine system?

In Traditional Chinese Medicine (TCM), the endocrine system is closely tied to the internal balance of Yin and Yang energies within the body. Imbalances in these energies can lead to various endocrine disorders, and TCM practitioners use a range of modalities, such as acupuncture and herbal remedies, to help restore this essential balance and support the overall functioning of the endocrine system.

Why is it important to have a good understanding of the endocrine system?

Understanding the critical role the endocrine system plays in our overall health and well-being can empower us to take proactive steps to support its optimal functioning. By recognizing the interconnectedness of the endocrine system with our physical, mental, and emotional well-being, we can make more informed choices and adopt strategies that promote greater balance, vitality, and resilience in the face of life’s challenges.

How can the endocrine system impact our physical health?

The endocrine system is responsible for regulating a wide range of physiological processes, including growth, metabolism, sexual function, and immune system function. Imbalances in the hormones produced by the endocrine glands can lead to a variety of physical health issues, such as weight fluctuations, reproductive problems, and compromised immune function. Maintaining the optimal functioning of the endocrine system is essential for overall physical well-being.

Organic India Clean

Shining the Light on the Forgotten System

It’s not usually a topic of conversation around the dinner table or something you’d choose to
read up on, as most people would consider the functioning of the endocrine system to be a
tad dry. Yet, understanding the basics of this vital and fascinating system of the body can
make a huge difference to your life.

Our endocrine glands can impact every area of our health. The endocrine system is made up
of glands that produce and secrete hormones. It is responsible for the hormonal functions
in the body, with the 30 hormones produced each having a very specific job to do. We all
know the impact of whacky hormones, and it’s fair to say, it’s not good!

If one gland’s function is out of balance, it can affect the health of all the others, and
the glands affect the function of the entire body. Not only does the endocrine system work
on the physical realm, but also on the emotional and energetic realms. It is highly beneficial
and empowering to understand how we can nurture our own bodies and support the optimal functioning
of these glands.

With a few simple tricks, you can easily keep your body in tune and enjoy greater happiness
and balance.

A Basic Guide to The Endocrine System

The endocrine system is a major, yet sometimes overlooked, component of your body. While it has
many physical functions, such as regulating sleep, heart rate, metabolism, the immune system,
and so much more, it is vital to mental functionality and mood.

The human Endocrine system plays a major role in our health and wellbeing.

Looking at the important gland centres of the body – the hypothalamus, the pituitary, thyroid,
parathyroid, the adrenals, pancreas, pineal gland, ovaries and testes – we begin to understand
why this system is so important. But the liver, pancreas, stomach, small intestine, kidneys,
and the placenta are all also part of the endocrine system. So if you’re feeling a little
down, touchy, or just plain grouchy, perhaps your endocrine system is suffering.

Together, the hypothalamus and the pituitary regulate all processes related to survival in
general, such as hunger, thirst, sexual activity, body temperature, stress, and fight or
flight. The hypothalamus tells the pituitary what to do, and then the pituitary tells the
other endocrine organs what to do. You can imagine it like a control centre with a chain
of command and if anything falls apart in this chain of command, the body’s balance can go
awry. The endocrine organ hormones feed back to the hypothalamus, telling it when to turn
on or off. The hypothalamus is the go-between of the endocrine system, nervous system, and
the immune system. There is a powerful relationship between the endocrine system and the
central nervous system and the two systems are synergistic. Most illness is caused by imbalance
and stress, and we all know that if your nervous system is optimal you will deal with stress
better, and have optimum wellbeing.

The hormone secretions are a language; a dance, that keeps us energetically stable, balanced
and feeling supported. When it is not in equilibrium we feel tired, heavy and unsupported.
Stress plays a big part in destabilising our endocrine function and, consequently, our nervous
system too.

Chinese Medicine and The Endocrine System

In Traditional Chinese Medicine (TCM), the endocrine system is closely tied to the internal balance
of Yin and Yang energies in the body. Although imbalance between the Yin and Yang energy
is the basis of any human disease, the most important element for endocrine disorder treatment
is centered on the kidney meridian

Meridians are channels of energy that run throughout our bodies.

Western physiology and anatomy limits its description of the kidney to the actual organ itself,
while TCM assigns it major significance with the ‘kidney’ as the home of the ‘ancestral chi’
(inherent constitution) and the root of yin and yang for the entire body. TCM also recognises
the prominent hormone regulating role played by the adrenals, which are two endocrine glands
attached to the superior surface of the kidneys, and just how important they are in the regulation
of the autonomic nervous system.

The kidney meridian is known as the root of life and the reservoir of energy; the seat of
courage and willpower.

The Chakras and The Endocrine System

The ancient Greek philosopher, Plato, saw the spinal energy centres, or chakras, as being the
subtle organs of the soul in establishing dominion over the mind and body. Plato said that
the soul manifested in three forms.

The highest level of soul expression he called the logos, psyche or immortal soul. It’s found
in the eyebrow centre and associated with the endocrine gland, the pituitary and Hypothalamus
or master gland of the endocrine system. He called the middle level of soul expression thymos,
the mortal soul, the aspect that is in charge of the body and its vital expression, and its
associated endocrine gland is the thymus gland. The third or lowest level epithymia

, is concerned with our basic survival instincts and is at the root centre, associated with
the endocrine glands, the adrenals. So embedded in the chakra system is the endocrine glands,
with perhaps the most important endocrine glands – the adrenals – and the base chakra forming
the basic energetic support or foundation for the entire organism.

Hermeticists and other esoteric philosophers noticed that every chakra is linked to an endocrine
gland: the crown chakra with the pineal, the brow centre with the pituitary and hypothalamus,
the throat centre with the thyroid gland, the heart centre with the thymus gland, solar plexus
with pancreas, sacral chakra with the reproductive organs and the base chakra with adrenals.

The chakras are said to correlate with the different glands of the endocrine system.

They then reasoned that the function of the associated endocrine gland must have something to
do with the spiritual, psychological, psychosomatic and physiological functions attributed
to the chakra, or energy center.

Endocrine Disruptors

Stress, infection and inflammation, sleep, exercise and diet – especially minerals and fluid
balance – all have an impact on hormone levels. Synthetic organic chemicals have a negative
impact on the human endocrine system and they place stress on human reproduction, growth
and/or development.

The endocrine disruptors mimic or block hormones and disrupt the way the body normally works
through the functional impairment of the endocrine glands.

Typical symptoms of the endocrine disorders include low immunity, fatigue, weight gain, depression,
digestive issues, hair loss, arthritis, and feeling chilled regardless of the temperature.

Creating Endocrine Balance

The entire endocrine system works together to control the level of hormones circulating throughout
your body, and if one or more hormones are even slightly imbalanced, it can cause widespread
and major health problems.

Healthy, unprocessed fats promote optimal endocrine function.

There are some simple ways we can balance our hormones naturally. Eating healthy fats, like coconut
oil and avocados, go a long way to supporting hormonal balance. Supplementing your diet with
adaptogen herbs – a unique class of healing plants that promote hormone balance, boost immune
function and protect the body from diseases, especially those caused by excess stress – such
as Ashwagandha, medicinal mushrooms, Rhodiola and Holy Basil, can have a powerful effect
on the body. Dairy is a big no-no for taking care of your hormones because dairy contains
numerous natural hormones that weren’t meant to be combined with our own.

Reducing the impact of chemicals on the body, by eating wholesome natural food, and eliminating
toxic kitchen, beauty and body care products go a long way to supporting hormonal health.

Of course, exercise is vital for hormonal balance too. For people with hormonal imbalances,
the key with exercise is to be careful not to overdo it. Reducing stress and ensuring you
get enough sleep are vital to happy hormones. Cortisol, the primary ‘stress hormone’, is
regulated at midnight. So people who go to bed late never truly get a break from their sympathetic
flight/fight stress response.

Balancing Hormones with Yoga

Yoga is one of the best ways to balance the endocrine system. Practices like Yoga Nidra or yogic
sleep, are a great way to control stress and emotion through encouraging the autonomic nervous
system and the digest, rest response which is so nourishing to our entire system. Yogic breathing
supports the hypothalamus and other glands, helping to balance the endocrine system. And
of course, yoga asana (or poses) have a direct action on the endocrine organs, through twists,
inversions and other poses which massage and stimulate the organs such as the kidneys, liver
and pancreas, encouraging hormone production and flow. The chakras and endocrine glands align
and communicate in important ways, and by practising yoga we can support greater hormonal
balance through harmonised chakras.

Yoga asana (poses), pranayama (breathing), and Nidra (sleep) also balance our hormones.

The endocrine network ‘talks’ to the other systems within the body to control everything from
growth and development to how energetic a person feels. It controls the process of hormonal
balance, special chemicals produced, stored, and distributed by glands and organs within
the body.

Many yoga poses stimulate and/or activate certain glands and organs, maintaining hormone
balance and consistent production and distribution. Specific yoga poses include all twists,
rabbit pose, forward bends and shoulder stand.

We can easily improve our health and vitality by taking care of this amazing regulatory system
of the body, the endocrine system. When our hormones are balanced we feel happy and able
to go out into the world and live our purpose with enthusiasm and joy. Our relationships
are improved and life flows.

Source credits: This article originally appeared on
UPLIFT Connect. It was written by Writer, Editor, Yoga Teacher and Healing Facilitator,
Azriel Re’Shel, and
UPLIFT Contributing Writer, Tanja Taljaard. UPLIFT is a global media channel dedicated
to inspiring positive change.

Major Endocrine Glands Names Locations Products – Endocrine System Hormones And Their Sources

The main endocrine glands are the hypothalamus, pituitary (anterior and posterior), thyroid, parathyroid, adrenal (cortex and medulla), pancreas, and gonads. All these glands together form the endocrine system.

1. The hypothalamus is an endocrine organ located in the brain. The hypothalamus synthesizes hormones such as ADH and oxytocin. The hypothalamus also synthesizes and secretes regulatory hormones that control the endocrine cells in the anterior pituitary gland such as Gonadotropin-Releasing Hormone, Thyrotropin Releasing Hormone, Growth Hormone Releasing Hormone and somatostatin.

2. The pituitary gland, sometimes called the “master gland,” is located at the base of the brain. The pituitary has two distinct regions: the anterior pituitary and the posterior pituitary.

The anterior pituitary produces seven hormones: growth hormone (GH), prolactin (PRL), thyroid-stimulating hormone (TSH), melanin-stimulating hormone (MSH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH). Anterior pituitary hormones are sometimes referred to as tropic hormones because they control the functioning of other organs. While these hormones are produced by the anterior pituitary, their production is controlled by regulatory hormones produced by the hypothalamus. The antidiuretic hormone (ADH) (or vasopressin) and oxytocin are produced by neurons in the hypothalamus and transported to the posterior pituitary. They are released into the circulatory system via neural signalling from the hypothalamus. These hormones are considered to be posterior pituitary hormones even though they are produced by the hypothalamus since that is where they are released into the circulatory system.

3. The thyroid gland, one of the largest endocrine glands in the body, is located in the neck, just below the larynx and in front of the trachea. The thyroid gland produces the hormones T3 (triiodothyronine) and T4 (thyroxine). These hormones increase the metabolic activity of the body‘s cells.

4. The parathyroid glands are small endocrine glands that produce parathyroid hormone. Most people have four parathyroid glands; however, the number can vary from two to six. These glands are located on the posterior surface of the thyroid gland.

5. Adrenal glands are a pair of ductless glands located above the kidneys. The adrenal glands produce glucocorticoids and androgens, which are sex hormones that promote masculinity. Androgens are produced in small amounts by the adrenal cortex in both males and females. They do not affect sexual characteristics and may supplement sex hormones released from the gonads. The adrenal medulla contains large, irregularly-shaped cells that are closely associated with blood vessels. The adrenal glands also produce epinephrine (adrenaline) and norepinephrine (noradrenaline) in response to stress.

6. The pancreas is an elongated organ that is located between the stomach and the proximal portion of the small intestine. It contains both exocrine cells that excrete digestive enzymes and endocrine cells that release hormones. As an endocrine gland, the pancreas produces several important hormones, such as insulin and glucagon in the islets of Langerhans, which are secreted into the bloodstream to regulate blood sugar levels.

7. The pineal gland is a small endocrine gland in the brain. It is located near the center of the brain, between the two hemispheres. The main hormone produced and secreted by the pineal gland is melatonin.

8. The gonads are additional types of endocrine glands. They are the sex organs and include the male testes and female ovaries. Their main role is the production of steroid hormones. The testes produce androgens, which allow for the development of secondary sex characteristics and the production of sperm cells. The ovaries produce hormones, such as estrogen and progesterone, which cause secondary sex characteristics and prepare the body for childbirth.

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Key Points 

• The hypothalamus synthesizes hormones and transports them to the posterior pituitary gland while also synthesizing and secreting regulatory hormones that control cells in the anterior pituitary gland.

• The anterior pituitary gland, regulated by the hypothalamus, produces seven tropic hormones, growth hormone (GH), prolactin (PRL), thyroid-stimulating hormone (TSH), melanin-stimulating hormone (MSH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH), which control the functioning of other organs.

• The posterior pituitary stores hormones produced by the hypothalamus (ADH and oxytocin) and release them into the bloodstream; the gland does not actually produce any hormones.

• The thyroid gland produces T3, T4 and calcitonin hormones.

• Parathyroid glands are responsible for the regulation of the body’s calcium and phosphorus levels by producing parathyroid hormone, which helps control calcium release.

• The two major hormones produced by the adrenal cortex are the mineralocorticoids, which regulate the salt and water balance, and the glucocorticoids, which can regulate blood glucose and the body’s inflammatory response.

• There are three main glucocorticoids: cortisol, corticosterone, and cortisone.

• The adrenal medulla produces the hormones epinephrine and norepinephrine; these hormones regulate heart rate, breathing rate, cardiac muscle contractions, blood pressure, and blood glucose levels.

• Glucagon and insulin are examples of hormones created by the pancreas that regulate the blood sugar levels.

• The pineal gland, a small endocrine gland in the brain, is responsible for producing hormone melatonin involved in the regulation of biological rhythms, mainly circadian rhythms.

• The gonads (the testes in males and ovaries in females) are responsible for the production of steroid hormones, such as testosterone, estrogen, and progesterone.

Key Terms

Hypothalamus: a region of the forebrain located below the thalamus that regulates body temperature, some metabolic processes and governs the autonomic nervous system

Glucocorticoid: any of a group of steroid hormones, produced by the adrenal cortex, that are involved in metabolism and have anti-inflammatory properties

Epinephrine: (adrenaline) an amino acid-derived hormone secreted by the adrenal gland in response to stress

Islets of Langerhans: regions in the pancreas that contain its endocrine cells

Exocrine: producing external secretions that are released through a duct

Androgen: the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of masculine characteristics in vertebrates.

Oxytocin: a hormone that stimulates contractions during labor, and then the production of milk

Antidiuretic hormone: a hormone secreted by the hypothalamus to control water levels in the body

Parathyroid hormone: a hormone secreted by the parathyroid glands that regulate the calcium concentration of blood

Melatonin: a hormone that regulates the sleep-wake cycle

Biology Endocrine glands and their functions

Human organ systems perform strictly defined functions, and in order for the body to exist as a whole, it is necessary to regulate and coordinate this complex work. This regulation is carried out by the nervous and humoral systems. Humoral regulation is carried out due to the release of hormones into the internal environment of the body, which are produced by the endocrine glands.

Endocrine glands, or endocrine glands, do not have excretory ducts. The products of their vital activity – hormones – they secrete into the internal environment of the body: into the blood, lymph or tissue fluid. it is formed by endocrine glands. While the glands of external secretion – sweat, salivary, sebaceous, gastric – secrete the products of their vital activity into the external environment or body cavities.

Entering the bloodstream, the hormone is distributed throughout the body and carries out humoral regulation of the functions of organs and tissues, changing their activity, stimulating or inhibiting their work.

The most important endocrine glands are the thyroid, parathyroid, thymus, adrenal and pituitary glands.

There are also glands of mixed secretion in the body, which produce several waste products. Some of them enter the bloodstream, and some go through the ducts into the cavity of the internal organs. This type of gland includes the pancreas and gonads.

The product of the vital activity of the endocrine glands is a hormone. The term “hormone” (from the Greek “I excite”, “I induce”) was introduced into practice by W. Bayliss and E. Starling. In January 1902, they conducted an experiment that convincingly proved the participation of the humoral factor in the regulation of the secretory activity of the pancreas. According to Bayliss and Starling, a hormone is any substance normally produced by the cells of any part of the body and carried by the blood to the distant parts on which it acts.

Currently, hormones are defined as highly active substances formed in the endocrine glands, entering the bloodstream and exerting a regulatory influence on the functions of organs and body systems remote from their place of secretion.

According to the chemical structure, hormones are divided into:

– hormones – derivatives of amino acids;

– protein and polypeptide hormones;

– steroid hormones.

According to the physiological effect – on launchers and performers. Trigger hormones (activators of the activity of other endocrine glands) include neurohormones of the hypothalamus and tropic hormones of the pituitary gland. Hormones-performers have a direct effect on the functions of the body.

Hormones are distinguished by a strict specificity of action – the reactions of organs, tissues and cells to them are strictly selective. Hormones act even in negligible amounts, but they are quickly destroyed, and therefore must be synthesized by the glands as needed and enter the bloodstream.

The thyroid gland is the largest of the endocrine glands, its mass is 16-23 g. It is located on both sides of the trachea just below the thyroid cartilage of the larynx. Thyroid hormones (thyroxine and triiodothyronine) contain iodine. Its intake with water and food is a necessary condition for the normal functioning of the gland.

Thyroid hormones regulate metabolism, enhance oxidative processes in cells and the breakdown of glycogen in the liver, affect the growth, development and differentiation of tissues, as well as the activity of the nervous system.

The adrenal glands are paired glands adjacent to the upper poles of the kidneys. Like the kidneys, the adrenal glands have two layers: the outer one is the cortical layer, and the inner one is the medulla, which are independent secretory organs. They produce different hormones with different patterns of action.

The cells of the cortical layer synthesize cortisol and corticosterone, which regulate mineral, carbohydrate, protein and fat metabolism. So, with their participation, the level of sodium and potassium in the blood is regulated, a certain concentration of glucose is maintained, the formation and deposition of glycogen in the liver and muscles increases. The last two functions of the adrenal glands are performed in conjunction with pancreatic hormones.

The adrenal medulla produces adrenaline and norepinephrine, which are released during strong emotions – anger, fear, pain, danger. The entry of these hormones into the blood causes a rapid heartbeat, narrowing of blood vessels, increased blood pressure, increased breakdown of glycogen in liver cells and muscles to glucose, inhibition of intestinal motility, relaxation of bronchial muscles, increased excitability of retinal receptors, auditory and vestibular apparatus. As a result, the functions of the body are rebuilt, forces are mobilized to endure stressful situations.

The pancreas is a mixed secretion gland. It has special islet cells that produce insulin and glucagon, which regulate carbohydrate metabolism in the body. So, insulin increases the consumption of glucose by cells, promotes the conversion of glucose into glycogen, thus reducing the amount of sugar in the blood. Due to the action of insulin, the blood glucose content is maintained at a constant level, favorable for the flow of vital processes.

Another pancreatic hormone – glucagon – is an insulin antagonist, has the opposite effect, that is, it enhances the breakdown of glycogen to glucose, increasing its content in the blood.

The gonads, the testes, or testicles in men and the ovaries in women, are glands of mixed secretion. The testicles produce androgens and the ovaries produce estrogens. They stimulate the development of reproductive organs, the maturation of germ cells and the formation of secondary sexual characteristics, that is, the structural features of the skeleton, the development of muscles, the distribution of hairline and subcutaneous fat, the structure of the larynx, the timbre of the voice in men and women.

The most important gland of the human endocrine system is the pituitary gland, or the lower appendage of the brain weighing only 0.5 g. It is located at the base of the brain – in the so-called “Turkish saddle”. The pituitary gland produces hormones that stimulate the functions of other endocrine glands.

In the pituitary gland, there are two main sections: the anterior lobe – adenohypophysis and the posterior – neurohypophysis, each of them produces certain hormones. So, in the anterior pituitary gland, hormones are produced that stimulate the synthesis and secretion of thyroid hormones (thyrotropin), adrenal glands (adrenocorticotropin), gonads (gonadotropin), as well as growth hormone (somatotropin).

Vasopressin and oxytocin are synthesized in the posterior pituitary gland. Vasopressin, or antidiuretic hormone, regulates water metabolism and vascular tone. Oxytocin increases the tone of the smooth muscles of the uterus, regulates the birth act and the secretion of milk by the mammary glands.

The pituitary gland is located directly below the hypothalamus and is connected to it by a funnel and a stalk. The hypothalamus is a part of the brain that has properties of the nervous and endocrine systems. The hypothalamus receives an extensive flow of information from the senses and internal organs. The composition of the neurosecretory nuclei of the hypothalamus includes the so-called large and small cell nuclei. The former secrete oxytocin and vasopressin, which are transported along the nerve trunks to the posterior pituitary gland, accumulate there and are used as needed. Other functions are performed by the small cell nuclei of the hypothalamus. They are able to develop the so-called releasing factors (allowing factors). Releasing factors through the venous system reach the pituitary gland and regulate the release of hormones of the latter.

All endocrine glands are interconnected. Hormones produced by some glands affect the activity of other glands. This provides a unified system of coordination, which is carried out according to the feedback principle: a decrease in the level of a peripheral hormone in the blood leads to an increase in the secretion of the corresponding tropic hormone, and an increase in the level of a peripheral hormone causes inhibition of the secretion of the tropic hormone.

Thus, the endocrine regulation of the body’s vital activity is complex and strictly balanced. Changes in physiological and biochemical reactions under the action of hormones contribute to the adaptation of the body to constantly changing environmental conditions.

For many years, scientists believed that hormones could only be produced by specialized endocrine glands or groups of cells whose sole function was to produce hormones. Currently, scientists believe that almost all organs and tissues of a living organism secrete hormones and biologically active compounds into the intercellular space and blood, through which interactions are carried out that unite cells and tissues into a single whole. So, the synthesis of hormones is found in the cells of the blood and the immune system, in the retina of the eye, in the cells lining the intestines and blood vessels, in the heart muscles. Most likely, this list will expand in the future.

Endocrine glands

Biologically active substances – hormones – are of great importance in the life of humans and animals. They are produced by special glands richly supplied with blood vessels. These glands do not have excretory ducts, and their hormones enter directly into the bloodstream, and then are carried throughout the body, carrying out humoral regulation of all functions: they excite or inhibit the activity of the body, affect its growth and development, change the intensity of metabolism. Due to the absence of excretory ducts, these glands are called glands of internal secretion, or endocrine, in contrast to the digestive, sweat, sebaceous glands of external secretion, having excretory ducts.

According to the structure and physiological action hormones are specific: each hormone has a powerful effect on certain metabolic processes or the work of an organ, causing a slowdown or, conversely, an increase in its function. The endocrine glands include the pituitary gland, thyroid gland, parathyroid glands, adrenal glands, insular part of the pancreas, intrasecretory part of the gonads. All of them are functionally interconnected: hormones produced by some glands affect the activity of other glands, which provides a single system of coordination between them, which is carried out on the principle of feedback. The leading role in this system belongs to the pituitary gland, whose hormones stimulate the activity of other endocrine glands.

Pituitary gland is one of the central endocrine glands, located under the base of the brain and has a mass of 0.5-0.7 g. The pituitary gland consists of three lobes: anterior, middle and posterior, surrounded by a common capsule of connective tissue. One of the anterior lobe hormones affects growth. An excess of this hormone at a young age is accompanied by a sharp increase in growth – gigantism, and with increased function of the pituitary gland in an adult, when body growth stops, an increased growth of short bones occurs: tarsus, metatarsus, phalanges of the fingers, as well as soft tissues (tongue, nose). This disease is called acromegaly. Decreased function of the anterior pituitary leads to dwarf growth. Pituitary dwarfs are proportionately built and normally mentally developed. In the anterior lobe of the pituitary gland, hormones are also formed that affect the metabolism of fats, proteins, carbohydrates. The posterior pituitary gland produces antidiuretic hormone, which reduces the rate of urine formation and changes the body’s water metabolism.

The thyroid gland is located in the anterior region of the neck, weighs 30-60 g and consists of two lobes connected by an isthmus. Inside the gland there are small cavities, or follicles, filled with a mucous substance containing the hormone thyroxine. The hormone contains iodine. This hormone affects the metabolism, especially fats, the growth and development of the body, increases the excitability of the nervous system, the activity of the heart. With the growth of thyroid tissue, the amount of hormone entering the bloodstream increases, which leads to a disease called Graves’ disease. The patient’s metabolism increases, which is expressed in severe emaciation, increased excitability of the nervous system, increased sweating, fatigue, bulging eyes.

When the function of the thyroid gland is reduced, the disease myxedema occurs, manifested in mucous tissue edema, slowing down metabolism, growth and development retardation, memory impairment, mental impairment. If this happens in early childhood, develops cretinism (dementia), characterized by mental retardation, underdevelopment of the genital organs, dwarf growth, disproportionate body structure. In mountainous areas there is a disease known as endemic goiter, resulting from a lack of iodine in drinking water. At the same time, the gland tissue, growing, compensates for the deficiency of the hormone for some time, but even in this case it may not be enough for the body. In order to prevent endemic goiter, residents of the respective zones are supplied with iodine-enriched table salt or added to water.

Adrenal glands – paired glands located at the upper edge of the kidneys. Their mass is about 12 g each, together with the kidneys they are covered with a fatty capsule. They distinguish between a cortical, lighter substance, and a cerebral, dark one. In the cortical layer, several hormones are produced – corticosteroids, that affect salt and carbohydrate metabolism, promote the deposition of glycogen in the liver cells and maintain a constant concentration of glucose in the blood. With insufficient function of the cortical layer, Addison’s disease, accompanied by muscle weakness, shortness of breath, loss of appetite, decrease in blood sugar concentration, decrease in body temperature. The skin at the same time acquires a bronze hue – a characteristic sign of this disease. In the adrenal medulla, the hormone adrenaline is produced. Its action is diverse: it increases the frequency and strength of heart contractions, increases blood pressure (at the same time, the lumen of many small arteries narrows, and the arteries of the brain, heart and renal glomeruli expand), increases metabolism, especially carbohydrates, accelerates the conversion of glycogen (liver and working muscles) into glucose, as a result of which the working capacity of the muscles is restored.

The pancreas functions as a mixed gland whose hormone – insulin – is produced by the cells of the islets of Langerhans. Insulin regulates carbohydrate metabolism, i.e., promotes the absorption of glucose by cells, maintains its constancy in the blood, converting glucose into glycogen, which is deposited in the liver and muscles. The second hormone of this gland is glucagon . Its action is opposite to insulin: when there is a lack of glucose in the blood, glucagon promotes the conversion of glycogen into glucose. With a reduced function of the islets of Langerhans, the metabolism of carbohydrates, and then proteins and fats, is disturbed. The content of glucose in the blood increases from 0.1 to 0.4%, it appears in the urine, and the amount of urine increases to 8-10 liters. This disease is called0067 diabetes mellitus. It is treated by injecting human insulin extracted from animal organs.

The activity of all endocrine glands is interconnected: hormones of the anterior pituitary gland promote the development of the adrenal cortex, enhance insulin secretion, affect the flow of thyroxine into the blood and the function of the gonads.