Endocrine system parts and function. Endocrine System: Anatomy, Function, Glands, and Hormones Explained

12.07.202328.06.2023 by alexxlab

What is the endocrine system and how does it work. Which glands make up the endocrine system. How do hormones affect our body. What are the main functions of the endocrine system. How does the endocrine system regulate bodily processes.

Содержание

The Endocrine System: An Overview of Glands and Hormones

The endocrine system is a complex network of glands and organs that produce and secrete hormones directly into the bloodstream. These hormones act as chemical messengers, traveling throughout the body to regulate various physiological processes. Understanding the intricate workings of the endocrine system is crucial for comprehending how our bodies maintain balance and respond to internal and external stimuli.

The endocrine system plays a vital role in numerous bodily functions, including:

Metabolism regulation
Growth and development
Mood and emotional balance
Reproductive processes
Stress response
Tissue function
Sleep cycles

By producing and releasing hormones, the endocrine system influences nearly every cell, organ, and function in our bodies. This intricate system works in tandem with the nervous system to maintain homeostasis and ensure proper bodily functions.

Major Glands of the Endocrine System: Location and Function

The endocrine system comprises several major glands, each with specific functions and hormone production. These glands work together to maintain balance within the body.

Hypothalamus: The Control Center

Located in the lower central part of the brain, the hypothalamus serves as a crucial link between the endocrine and nervous systems. It gathers information from various sources, including temperature, light exposure, and emotions, and relays this data to the pituitary gland. The hypothalamus produces chemicals that control hormone release from the pituitary, effectively acting as a control center for many endocrine functions.

Pituitary Gland: The Master Gland

Despite its small size (no larger than a pea), the pituitary gland is often referred to as the “master gland” due to its influence on other endocrine glands. Situated at the base of the brain, it produces a wide array of hormones that regulate various bodily functions.

Key hormones produced by the pituitary gland include:

Growth hormone: Stimulates bone and tissue growth
Prolactin: Activates milk production in breastfeeding women
Thyroid-stimulating hormone: Regulates thyroid gland function
Adrenocorticotropic hormone: Stimulates adrenal gland hormone production
Antidiuretic hormone: Controls body water balance
Oxytocin: Triggers uterine contractions during labor

The pituitary gland also secretes endorphins, which help reduce pain perception, and hormones that signal reproductive organs to produce sex hormones. Additionally, it plays a crucial role in controlling ovulation and the menstrual cycle in women.

Thyroid Gland: Metabolism Regulator

The butterfly-shaped thyroid gland, located in the front part of the lower neck, produces thyroxine and triiodothyronine. These hormones are essential for regulating metabolism, controlling the rate at which cells convert food into energy. Thyroid hormones also play a vital role in bone growth and development, as well as in the maturation of the brain and nervous system.

Parathyroid Glands: Calcium Balance Guardians

Four tiny parathyroid glands are attached to the thyroid gland. These glands work together to release parathyroid hormone, which regulates calcium levels in the blood. This process is supported by calcitonin, a hormone produced by the thyroid gland. The interplay between these hormones ensures proper calcium balance, which is crucial for various bodily functions, including bone health and muscle contractions.

Adrenal Glands: Stress Response and Metabolism

The two triangular adrenal glands, situated atop each kidney, consist of two distinct parts with different functions:

Adrenal cortex (outer part): Produces corticosteroids that regulate salt and water balance, stress response, metabolism, immune function, and sexual development.
Adrenal medulla (inner part): Secretes catecholamines, such as epinephrine (adrenaline), which increase blood pressure and heart rate during stress.

Pineal Gland: Sleep-Wake Cycle Regulator

The pineal gland, located in the middle of the brain, secretes melatonin. This hormone plays a crucial role in regulating the sleep-wake cycle, also known as the circadian rhythm. Melatonin production is influenced by light exposure, with levels typically increasing in darkness and decreasing in light.

Hormones: The Chemical Messengers of the Endocrine System

Hormones are the key players in the endocrine system, acting as chemical messengers that travel through the bloodstream to target specific cells or organs. These powerful compounds can influence various bodily functions, from metabolism and growth to mood and reproduction.

How do hormones exert their effects on the body? Hormones work by binding to specific receptors on target cells. This binding triggers a cascade of events within the cell, leading to changes in cellular function or activity. The specificity of hormone-receptor interactions ensures that hormones only affect their intended targets, even though they circulate throughout the entire body.

Types of Hormones

Hormones can be classified into several categories based on their chemical structure:

Amino acid-derived hormones: Examples include epinephrine and thyroid hormones
Peptide hormones: Such as insulin and growth hormone
Steroid hormones: Including sex hormones like estrogen and testosterone

Each type of hormone has unique properties that influence how it is produced, transported, and metabolized in the body.

Endocrine System Regulation: Maintaining Balance

The endocrine system employs various mechanisms to regulate hormone levels and maintain homeostasis. This delicate balance is crucial for optimal bodily function and overall health.

Feedback Loops

One of the primary regulatory mechanisms in the endocrine system is the feedback loop. There are two main types:

Negative feedback loops: These help maintain hormone levels within a narrow range. When hormone levels rise too high, the system signals a reduction in hormone production.
Positive feedback loops: Less common, these loops amplify hormone production in specific situations, such as during childbirth or ovulation.

Factors Influencing Hormone Levels

Several factors can affect hormone levels in the body, including:

Stress
Infection
Changes in fluid and mineral balance
Diet and nutrition
Physical activity
Environmental factors

Understanding these influences is crucial for maintaining endocrine health and addressing hormonal imbalances.

Endocrine Disorders: When the System Malfunctions

Endocrine disorders occur when glands produce too much or too little of a hormone, or when the body doesn’t respond properly to hormones. These imbalances can lead to various health issues, affecting growth, metabolism, reproduction, and other vital functions.

Common Endocrine Disorders

Some frequently encountered endocrine disorders include:

Diabetes mellitus: Impaired insulin production or utilization
Thyroid disorders: Hypothyroidism and hyperthyroidism
Adrenal insufficiency: Reduced cortisol production
Growth hormone deficiency: Impaired growth and development
Polycystic ovary syndrome (PCOS): Hormonal imbalance affecting ovarian function

Many endocrine disorders can be effectively managed with medication, lifestyle changes, or hormone replacement therapy. Early diagnosis and treatment are crucial for preventing complications and improving quality of life.

The Endocrine System and Overall Health: Connections and Implications

The endocrine system’s influence extends far beyond individual glands and hormones. Its intricate connections with other bodily systems highlight the importance of hormonal balance for overall health and well-being.

Endocrine-Immune System Interactions

The endocrine and immune systems are closely intertwined. Hormones can modulate immune responses, while immune cells can influence hormone production. This bidirectional communication plays a crucial role in maintaining health and fighting disease.

Endocrine System and Mental Health

Hormonal imbalances can significantly impact mental health. For example, thyroid disorders are often associated with mood changes, while cortisol imbalances can contribute to anxiety and depression. Understanding these connections is essential for comprehensive mental health care.

Hormones and Aging

As we age, hormone production and sensitivity can change, leading to various health issues. Hormonal changes associated with aging include:

Decreased growth hormone production
Reduced testosterone levels in men (andropause)
Declining estrogen and progesterone in women (menopause)
Changes in thyroid function

Managing these age-related hormonal changes can help maintain health and vitality in later years.

Advances in Endocrinology: Current Research and Future Directions

The field of endocrinology continues to evolve, with ongoing research shedding light on the complex workings of the endocrine system and paving the way for new treatments and interventions.

Emerging Technologies

Advancements in technology are revolutionizing endocrine research and treatment. Some promising areas include:

Artificial pancreas systems for diabetes management
Gene therapy for endocrine disorders
Bioengineered hormone replacements
Advanced imaging techniques for early detection of endocrine tumors

Personalized Medicine in Endocrinology

The concept of personalized medicine is gaining traction in endocrinology. By considering individual genetic profiles, lifestyle factors, and environmental influences, healthcare providers can tailor treatments to each patient’s unique needs, potentially improving outcomes and reducing side effects.

Environmental Endocrine Disruptors

Increasing attention is being paid to the impact of environmental chemicals on the endocrine system. These endocrine disruptors can interfere with hormone production, metabolism, or action, potentially leading to various health issues. Ongoing research aims to identify these compounds and develop strategies to mitigate their effects.

As our understanding of the endocrine system deepens, so does our ability to maintain hormonal balance and address endocrine disorders. The intricate dance of glands and hormones continues to fascinate researchers and healthcare providers alike, promising new insights and innovative treatments for the future.

Endocrine System

What Is the Endocrine System?

The endocrine system is made up of glands that make hormones. Hormones are the body’s chemical messengers. They carry information and instructions from one set of cells to another.

The endocrine (EN-duh-krin) system influences almost every cell, organ, and function of our bodies.

What Does the Endocrine System Do?

Endocrine glands release hormones into the bloodstream. This lets the hormones travel to cells in other parts of the body.
The endocrine hormones help control mood, growth and development, the way our organs work, metabolism , and reproduction.
The endocrine system regulates how much of each hormone is released. This can depend on levels of hormones already in the blood, or on levels of other substances in the blood, like calcium. Many things affect hormone levels, such as stress, infection, and changes in the balance of fluid and minerals in blood.

Too much or too little of any hormone can harm the body. Medicines can treat many of these problems.

What Are the Parts of the Endocrine System?

While many parts of the body make hormones, the major glands that make up the endocrine system are the:

hypothalamus
pituitary
thyroid
parathyroids
adrenals
pineal body
the ovaries
the testes

The pancreas is part of the endocrine system and the digestive system. That’s because it secretes hormones into the bloodstream, and makes and secretes enzymes into the digestive tract.

Hypothalamus: The hypothalamus (hi-po-THAL-uh-mus) is in the lower central part of the brain. It links the endocrine system and nervous system. Nerve cells in the hypothalamus make chemicals that control the release of hormones secreted from the pituitary gland. The hypothalamus gathers information sensed by the brain (such as the surrounding temperature, light exposure, and feelings) and sends it to the pituitary. This information influences the hormones that the pituitary makes and releases.

Pituitary: The pituitary (puh-TOO-uh-ter-ee) gland is at the base of the brain, and is no bigger than a pea. Despite its small size, the pituitary is often called the “master gland.” The hormones it makes control many other endocrine glands.

The pituitary gland makes many hormones, such as:

growth hormone, which stimulates the growth of bone and other body tissues and plays a role in the body’s handling of nutrients and minerals
prolactin (pro-LAK-tin), which activates milk production in women who are breastfeeding
thyrotropin (thy-ruh-TRO-pin), which stimulates the thyroid gland to make thyroid hormones
corticotropin (kor-tih-ko-TRO-pin), which stimulates the adrenal gland to make certain hormones
antidiuretic (an-ty-dy-uh-REH-tik) hormone, which helps control body water balance through its effect on the kidneys
oxytocin (ahk-see-TOE-sin), which triggers the contractions of the uterus that happen during labor

The pituitary also secretes endorphins (en-DOR-fins), chemicals that act on the nervous system and reduce feelings of pain. The pituitary also secretes hormones that signal the reproductive organs to make sex hormones. The pituitary gland also controls ovulation and the menstrual cycle in women.

Thyroid: The thyroid (THY-royd) is in the front part of the lower neck. It’s shaped like a bow tie or butterfly. It makes the thyroid hormones thyroxine (thy-RAHK-sin) and triiodothyronine (try-eye-oh-doe-THY-ruh-neen). These hormones control the rate at which cells burn fuels from food to make energy. The more thyroid hormone there is in the bloodstream, the faster chemical reactions happen in the body.

Thyroid hormones are important because they help kids’ and teens’ bones grow and develop, and they also play a role in the development of the brain and nervous system.

Parathyroids: Attached to the thyroid are four tiny glands that work together called the parathyroids (par-uh-THY-roydz). They release parathyroid hormone, which controls the level of calcium in the blood with the help of calcitonin (kal-suh-TOE-nin), which the thyroid makes.

Adrenal Glands: These two triangular adrenal (uh-DREE-nul) glands sit on top of each kidney. The adrenal glands have two parts, each of which makes a set of hormones and has a different function:

The outer part is the adrenal cortex. It makes hormones called corticosteroids (kor-tih-ko-STER-oydz) that help control salt and water balance in the body, the body’s response to stress, metabolism, the immune system, and sexual development and function.
The inner part is the adrenal medulla (muh-DUH-luh). It makes catecholamines (kah-tuh-KO-luh-meenz), such as epinephrine (eh-puh-NEH-frun). Also called adrenaline, epinephrine increases blood pressure and heart rate when the body is under stress.

Pineal: The pineal (pih-NEE-ul) body, also called the pineal gland, is in the middle of the brain. It secretes melatonin (meh-luh-TOE-nin), a hormone that may help regulate when we sleep at night and wake in the morning.

Reproductive Glands: The gonads are the main source of sex hormones. In boys the male gonads, or testes (TES-teez), are in the scrotum. They secrete hormones called androgens (AN-druh-junz), the most important of which is testosterone (tess-TOSS-tuh-rone). These hormones tell a boy’s body when it’s time to make the changes associated with puberty, like penis and height growth, deepening voice, and growth in facial and pubic hair. Working with hormones from the pituitary gland, testosterone also tells a boy’s body when it’s time to make sperm in the testes.

A girl’s gonads, the ovaries (OH-vuh-reez), are in her pelvis. They make eggs and secrete the female hormones estrogen (ESS-truh-jen) and progesterone (pro-JESS-tuh-rone). Estrogen is involved when a girl starts puberty. During puberty, a girl will have breast growth, start to accumulate body fat around the hips and thighs, and have a growth spurt. Estrogen and progesterone are also involved in the regulation of a girl’s menstrual cycle. These hormones also play a role in pregnancy.

Pancreas: The pancreas (PAN-kree-us) makes insulin (IN-suh-lin) and glucagon (GLOO-kuh-gawn), which are hormones that control the level of glucose, or sugar, in the blood. Insulin helps keep the body supplied with stores of energy. The body uses this stored energy for exercise and activity, and it also helps organs work as they should.

What Can Help Keep the Endocrine System Healthy?

To help keep your child’s endocrine system healthy:

Get plenty of exercise.
Eat a nutritious diet.
Go for regular medical checkups.
Talk to the doctor before taking any supplements or herbal treatments.
Let the doctor know about any family history of endocrine problems, such as diabetes or thyroid problems.

When Should I Call the Doctor?

Let the doctor know if your child:

drinks a lot of water but is still thirsty
has to pee often
has frequent belly pain or nausea
is very tired or weak
is gaining or losing a lot of weight
has tremors or sweats a lot
is constipated
isn’t growing or developing as expected

Endocrine system – Poultry Hub Australia

The Endocrine System

The endocrine system consists of a number of organs and major glands located in different areas of the body which play an important role in the proper functioning of the animal. The glands produce special compounds called hormones, which in turn, target particular systems or organs, and the way that they function. These glands are called endocrine glands because they do not have an opening to discharge their secretions but discharge them directly into the bloodstream. The hormones are then carried to their target systems and organs to carry out their task. In many cases, different hormones operate together to regulate a particular function. When these get out of balance, the bird’s body cannot function properly and hence performance will suffer, in some cases, an imbalance can even lead to death.

Pituitary gland or hypophysis

The pituitary gland is often called the master gland because many of the compounds it produces target other similar glands to trigger them to produce their compounds that, in turn, influence the functioning of a particular system or organ. Thus, it can be said it is a controlling gland.
The pituitary gland is a pea-sized gland located at the base of the brain and is well protected by the surrounding skull bones. It consists of two parts:

Anterior pituitary
Posterior pituitary

The anterior pituitary gland is stimulated by special releasing factors from the hypothalamus of the brain to produce and release a number of hormones. These include:

Thyroid Stimulating Hormone – stimulates the thyroid gland.
Adrenocorticotrophic Hormone – stimulates the adrenal cortex.
Sex hormones – stimulates the sex glands:
- Luteinising Hormone (LH)
- Follicle Stimulating Hormone (FSH)
Melanin Stimulating Hormone – function in birds is unknown.
Natural Growth Hormone – stimulates growth of the animal.

The quantity of these hormones produced by the pituitary gland will influence the level of activity of the target organ or response. The more that is produced, the greater will be the response. The posterior pituitary gland produces arginine vasotocin and stores oxytocin and Antidiuretic hormone (ADH, which is known as vasopressin) that are produced by the hypothalamus. Oxytocin plays a part in the release of the yolk into the oviduct and the actual laying of the egg or oviposition. Antidiuretic hormone acts on the kidney collecting ducts and positively affect the reabsorption of water into the blood. The secretions produced or stored in the pituitary gland enter the blood stream and are then transported to the part of the body that they target.

Hypothalamus

The hypothalamus is a major part of the brain and is located at the base and approximately in the skull. As far as its endocrine functions in the bird is concerned, they include the production of the releasing factors that act as a control on the anterior pituitary gland, and oxytocin that plays a part in the release of the yolk. The quantity of the releasing factors and oxytocin released is influenced by day length. The longer the day is to 18 hours, the greater the amount of these compounds released and the greater the effect on the target gland or function.

Adrenal gland

The adrenal glands are small glands approximately 9 mm long located anterior to (in front of) the kidneys. There are two adrenal glands, each associated with a particular kidney. Each gland consists of two different types of cells that form two distinct parts of the gland, namely the adrenal cortex and the adrenal medulla.

The cortex produces three hormones:

Corticosterone – facilitate the carbohydrate and fat metabolism, breakdown of protein and palys an important role in the bird’s reaction to stress
Aldosterone – increases the reabsorption and retention of sodium
8-hydroxycorticosterone – function unknown

The adrenal medulla produces two compounds:

Norepinephrine – fat metabolism
Epinephrine – control of blood pressure

Thyroid gland

The thyroid gland consists of two reddish purple glands that lie either side of the base of the neck. This gland produces two hormones:

Thyroxine – helps regulate heat production, carbohydrate metabolism, promotes high blood sugar level, and promotes growth
Triiodothyronine – development of skin and feathers; may be involved in the moulting process

Parathyroid glands

These are two small, round, yellowish-white glands located at the base of the thyroid glands at the base of the neck. They produce a hormone called parathormone which reacts to low blood calcium levels and works to increase the amount of calcium in the blood.

Ultimobranchial bodies

These are 1-3 mm long and are located just posterior to (behind) the parathyroid glands. They produce a hormone called calcitonin that works to reduce the calcium level in the blood stream. Thus, the hormones parathormone of the parathyroids and calcitonin of the ultimobranchial bodies must be in balance if the calcium levels in the blood are to be in balance to requirements.

Pineal body

The pineal body is a very small gland located above the mid-brain, that uses tryptophane (an amino acid) to produce melatonin. Melatonin affects sleep, behaviour and brain electrical activity. Thus the pineal body acts as a biological clock, and as such, has an effect on the activities of the hypothalamus and its production of releasing factors.

Islets of Langerhans

These are small clumps of special cells located in the pancreas, which sit in the duodenal loop of the small intestine. These special cells produce two hormones:

Insulin – lowers blood sugar
Glucagon – increases blood sugar and affects fatty acid levels

Gonads

The sex organs of males and females are called the gonads. These organs produce hormones called sex hormones and include:

Oestrogen – the primary female sex hormone which controls and regulates the female reproductive system and secondary sex characteristics.
Testosterone – the primary male sex hormone which plays an important role in the development of male reproductive tissues and promotes male secondary sexual characteristics
Progesterone – an endogenous steroid which is involved in the menstrual cycle, pregnancy, and embryogenesis. It also acts as an intermediate in the production of other endogenous steroids

Both males and females produce and need all three hormones but in different amounts. For example, when a male is castrated the balance of the sex hormones is affected which leads to the bird taking on female characteristics. This means that a capon, or castrated male, will over time, take on much of the appearance and behaviour of a female.

Further information

Bradley, OC (1960) The Structure of the Fowl, Tom Grahame ed, Oliver and Boyd, Edinburgh, UK.
Dingle, J.G. (1991) Poultry Husbandry 1: Study Book, DEC, USQ, Toowoomba, Australia.

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Endocrine system

ENDOCRINE
SYSTEM

Endocrine
organs and nervous system regulate and
coordinate the functions of our body.
Knowledge of the structure and functions of the endocrine system
system is the basis for studying
humoral regulatory mechanisms.
Study of the histophysiology of endocrine
organs is important for understanding disorders
humoral regulation that
necessary for physicians of all specialties
and especially endocrinologists.

General
characteristics of the endocrine system

B
The composition of the endocrine system includes
highly specialized secretory
organs (organs with purely endocrine
secretion) or parts of organs (in the glands
with mixed function), as well as single
endocrine cells scattered throughout
various non-endocrine organs (lungs,
kidneys, alimentary canal). basis
most endocrine glands (as well as
exocrine) is epithelial
textile. However, a number of organs (hypothalamus,
posterior lobe of the pituitary gland, pineal gland, medulla
adrenal substance, some
single endocrine cells) are
derivatives of nervous tissue (neurons
or neuroglia).

All
organs of the endocrine system produce
highly active and specialized
but the action of the substance is hormones. One and
the same endocrine gland can
to produce different
hormone action. At the same time, secretion
the same hormones can be carried out
various endocrine organs.
Morphological features of endocrine
bodies are the presence of a group
highly specialized secretory
cells or one such cell,
producing biologically active
substances – hormones that enter the blood
and lymph. Therefore, in the endocrine organs
there are no excretory ducts, and
endocrine cells are surrounded by dense
network of lymphatic and circulatory
sinusoidal capillaries. In the endocrine
secretory hormone-producing system
cells can be arranged in groups
strands, follicles or solitary
endocrinocytes. Hormones by chemical
nature are different: protein (STG),
glycoprotein (TSH), steroid (cortex
adrenals). In fact, hormones
are divided into “starters” and “executor hormones”.
Trigger hormones are
neurohormones of the central endocrine
hypothalamic organs and tropic hormones
pituitary. “Performing hormones”
peripheral endocrine glands or
target organs, as opposed to “launchers”
have a direct effect
on the basic functions of the body: adaptation,
metabolism, growth, sexual function and
others

B
The body has two regulatory
systems: nervous and endocrine.
The activity of the endocrine system in
ultimately regulated by the nervous
system. Relationship between nervous and endocrine
system through the hypothalamus
– part of the brain that is the highest
vegetative center. Its nuclei are formed
special neurosecretory neurons,
capable of producing not only
neurotransmitters (norepinephrine,
serotonin), like all neurons, but also
neurohormones, in particular liberins and
statins entering the bloodstream
channel and thus reaching
anterior pituitary gland. These neurohormones
are transmitters, switches
impulses from nervous to endocrine
system, on the adenohypophysis, stimulating with
with the help of the liberins, or by oppression through
statins produced by endocrinocytes
anterior pituitary triple hormones,
in turn affecting the products.
hormones from peripheral endocrine
glands. Thus, humoral
by, transhypophyseal hypothalamus
regulates the activity of peripheral
endocrine organs – target organs,
whose endocrine cells have
receptors for the corresponding hormones.
Hypothalamic regulation of endocrine
glands can also be performed parahypophyseally
along the chains of efferent neurons. In my
queue on the principle of “feedback”
endocrine glands are capable of directly
respond to your own hormones.
It should be noted that the regulatory role
the hypothalamus is controlled by higher
parts of the brain (limbic
system, epiphysis, reticular formation
etc.), the ratio of catecholamines,
serotonin, acetylcholine, and
endorphins and enkephalins produced by
specialized neurons in the brain.

Classification
organs of the endocrine system

1.
Central regulatory formations
endocrine system (neurosecretory
nuclei of the hypothalamus, pituitary gland, pineal gland).

2.
Peripheral endocrine glands:
pituitary-dependent (thyroid thyrocytes)
glands, adrenal cortex) and
pituitary-independent (parathyroid
iron, thyroid calcitoninocytes
glands, adrenal medulla).

3.
Organs with endocrine and non-endocrine
functions (pancreas, reproductive
glands, placenta).

4.
Solitary hormone-producing cells
(in the lungs, kidneys, digestive tube
etc.) of nervous origin and non-nervous.

Organs
endocrine system

HYPOPHYSIS
composed of adenohypophysis epithelial
genesis (anterior lobe, middle lobe and
tuberal part and neurohypophysis
neuroglial origin (posterior
share, funnel, stem). Anterior lobe
the pituitary gland is represented by epithelial
grouped endocrinocytes
and strands, between which in a loose
connective tissue are located
sinusoidal blood capillaries
type. Endocrinocytes are divided into days
large groups: chromophilic with good
staining granules and chromophobic
with slightly stained cytoplasm and
without granules. Among the chromophilic
cells distinguish basophilic with granules
containing glycoproteins and staining
basic dyes, and acidophilic
with large protein granules,
stained with acid dyes.
Basophilic endocrinocytes (4-10% of them)
include several types (depending on
from the produced hormone, see table
1 cells: thyrotropocytes – cells
polygonal shape, in their cytoplasm
contains small granules (80-150 nm),
oval or round gonadotropocytes
forms have granules (200-300 nm) and
eccentrically located nucleus, in
in the center of the cage – a light zone – “courtyard”
or macula (on the electronogram it is
golgi apparatus). Corticotropocytes –
irregularly shaped cells
special spherical granules (200-250 nm).
Acidophilic endocrinocytes (30-35%) have
well developed granular
endoplasmic reticulum and subdivided
per:

somatotropocytes
with granules with a diameter of 350-400 nm and
lactotropocytes with larger granules
500-600 nm in the cytoplasm. Chromophobic or
chief cells (60%) are either
undifferentiated reserve,
or cells in different functional
states. Hypothalamic regulation
adenohypophyseal hormone formation
carried out in a humoral way.
Superior pituitary artery in the area
medial hypothalamic eminence
breaks down into primary capillary
net. On the walls of these capillaries
end of the axons of the neurons of the middle
hypothalamus. along the axons of these neurons
their neurohormones liberins and statins
enter the blood. Primary capillaries
plexuses are collected in portal
vessels. The latter descend into the front
share and there they break up into a secondary
capillary network from which liberins
and statins diffuse to endocrinocytes
adenohypophysis.

Medium
the proportion of the pituitary gland in humans is poorly developed.
This lobe produces melanocytotropin
and lipotropin, which affects lipid
exchange. This portion consists of epithelial
cells and pseudofollicles – cavities
with secretion of albuminous or mucous
character.

Neurohypophysis
– the posterior lobe is represented by neuroglial cells
process-shaped cells – pituicytes.
This part of the pituitary gland itself does not produce,
but only accumulates hormones (ADH, oxytocin)
neurons of the nuclei of the anterior hypothalamus
and neurosecretory storage
Herring bodies. The latter are
axon endings of the cells of these neurons
on the walls of sinusoidal capillaries
posterior pituitary gland. neurohypophysis
refers to the neurohemal organs,
accumulating hypothalamic
hormones. The posterior pituitary is connected
with hypothalamus, pituitary stalk and
forms with it a single hypothalamic-pituitary
system.

Epiphysis

Epiphysis
or pineal gland
diencephalon cone
forms. The epiphysis is covered with connective tissue
capsule from which thin
septa with vessels and nerves dividing
organ into indistinct lobules. IN
organ lobules distinguish between two types of cells
neuroectodermal origin:
secretory pinealocytes
(endocrinocytes) and supporting
glial cells (gliocytes) with poor
cytoplasm and dense nuclei.
Pinealocytes are divided into two types: light
and dark. Light pinealocytes – large
process cells with homogeneous
cytoplasm. Dark cells have
granular cytoplasm (acidophilic or
basophilic granules). These two varieties
pinealocytes appear to represent
different functional states of one
cells. Processes of pinealocytes, club-shaped
expanding, contact with numerous
sinusoidal blood capillaries.
The involution of the pineal gland begins at 4-5 years of age.
age. After 8 years of age
epiphysis areas are found
calcified stroma (“brain
sand”), but the function of the gland does not stop.
The human pineal gland is able to capture
light stimulation and adjust
rhythmic processes in the body,
associated with the change of day and night.
hormones produced by the pineal gland
factors – serotonin, which is converted into
melatonin, antigonadotropin regulate
gonadal function through the hypothalamus
and eye. Among the hormonal factors
produced by the pineal gland, there is a hormone
increasing the level of potassium in the blood.

THYROID
IRON

Consists of
made up of two parts connected to each other
part of the gland called the isthmus.
Outside, the gland is covered with connective tissue
capsule from which thin
layers with vessels separating the organ
on slices. The main part of the parenchyma
lobules make up its structural and functional
units – follicles. These are the bubbles
wall of which is composed of follicular
endocrinocytes – thyrocytes. thyrocytes
– cuboidal epithelial cells
forms (with normofunction), secreting
iodine-containing hormones – thyroxine and
triiodothyronine, affecting the main
exchange. Follicles filled with colloid
(viscous liquid containing thyroglobulia).
Outside, the wall of the follicle is closely connected
with a network of circulatory and lymphatic
capillaries. With hypothyroidism
glands thyrocytes are flattened, colloid
compacted, the size of the follicles
increases, and vice versa, with hyperfunction
thyrocytes take a prismatic
shape, the colloid becomes more fluid
and contains numerous vacuoles. IN
the secretory cycle of the follicle is distinguished
the production phase and the excretion phase of the hormone.
Required for thyroxine production
iodides, amino acids, including tyrosine,
carbohydrate components, water, absorbed
thyrocytes from the blood. In the endoplasmic
networks of thyrocytes form a polypeptide
thyroglobulin chain, to which
Golgi complex join
carbohydrate components. Blood iodides from
with the help of peroxidases of thyrocytes are oxidized
to atomic iodine. At the border of thyrocytes
and the cavity of the follicle is switched on
iodine atoms in tyrosine polypeptide
thyroglobulin chains. As a result
mono- and diiodotyrosines are formed, and
further from them – tetraiodothyronine –
thyroxine and triiodothyronine. Hatch phase
proceeds with the reabsorption of the colloid by
phagocytosis of colloid fragments –
thyroglobulin pseudopodia of thyrocytes
with strong activation of the gland. Then
phagocytosed fragments under
by lysosomal enzymes
undergo proteolysis and released
from thyroglobulin iodothyronines are bought
from thyrocyte to blood capillaries
surrounding the follicle. moderate activity
thyroid is not accompanied
colloid phagocytosis. In this case
observed proteolysis in the cavity of the follicle
and pinocytosis of proteolysis products
thyrocyte. In connective tissue
stroma between follicles
small accumulations of epithelial
cells (interfollicular islets)
being a source of development of new
follicles. In the wall of the follicles
or in interfollicular islets
light neuronal cells are located
origin – parafollicular
endocrinocytes or calcitoninocytes
(K-cells). These endocrinocytes are
cytoplasm in addition to granules of neuramins
(serotonin, norepinephrine) specific
production-related graininess
protein hormones – calcitonin,
lowering the level of Ca in the blood, and
somatostatin. The production of these hormones
unlike the production of thyroxin, not
associated with iodine uptake and independent of
from pituitary thyrotropic hormone.
K-cell granules stain well
osmium and silver.

PAROTHYROID
IRON

Parenchyma
organ is represented by strands of epithelial
cells are parathyrocytes. Between them in
layers of connective tissue
there are numerous capillaries.
Distinguish the main ones – light with inclusions
glycogen and dark parathyroid cells, as well as
oxyphilic parathyrocytes with numerous
mitochindria. In the main cells
the cytoplasm is basophilic, with large
grains. acidophilic cells are considered
aging forms of the main ones. Parathormone
parathyroid and calcitonin
thyroid glands are antagonists
they maintain calcium homeostasis
in organism. Parathyrin production
has a hypercalcemic effect
and is independent of pituitary hormones.

ADRENAL

Paired
organs consist of an outer cortical
matter and the inner medulla
substances. In the cortex, there are
three zones of epithelial cells: glomerular,
producing mineralocorticoid
the hormone aldosterone, which
water-salt metabolism, sodium retention
in organism; bundle, producing
glucocorticoids that affect metabolism
carbohydrates, proteins, lipids, inhibitory
inflammatory processes and immunity;
reticular zone – producing genital
hormones-androgens, estrogens, progesterone.
The glomerular zone, located under
capsule, formed by strands of flattened
endocrinocytes that form clusters
– balls. In the cytoplasm of these cells
few lipid inclusions. Destruction
this zone leads to death. Products
there are practically no hormones in this zone
dependent on pituitary hormones. Under
glomerular zone has sudanophobic
lipid-free layer. Beam
zone – the widest and consists of strands
cubic cells containing many
lipid inclusions, when dissolved
which the cytoplasm becomes “spongy”.
The cells themselves are called
spongiocytes. In the beam zone, there are
two types of cells: light and dark,
which are different functional
states of the same endocrinocytes.
The mesh zone is represented by branched
strands of small secretory cells,
forming a network, in the loops of which
abundance of sinusoidal capillaries. Beam
and reticular cortex of the adrenal glands
are pituitary glands. For
adrenal cortex,
producing steroid hormones
characterized by good development of agranular
endoplasmic reticulum and mitochondria
with twisted, branching cristae.
The adrenal medulla is
derivatives of nerve cells. His
chromaffin cells or brain cells
endocrinocytes are divided into light –
epinephrocytes that produce adrenaline
and dark – norepinephrocytes producing
norepinephrine. These cells regenerate
oxides of chromium, silver, osmium. Hence them
names – chromaffin, osmiophilic,
argyrophilic. Chromaffinocytes secrete
epinephrine and noradrenaline in the surrounding
their many blood vessels,
among which there are especially many venous
sinusoids. brain activity
substance independent of pituitary hormones
and regulated by nerve impulses. IN
release of the body from stressful conditions
cortex and adrenal medulla
with their hormones participate together.

Comprehensive hormonal examination for men, find out the prices for a complex of analyzes and take it in Moscow

Synonyms: Hormonal profile for men; Male hormonal status.

Comprehensive hormonal examination for men; Men’s comprehensive hormonal exam.

Profile composition:

No. 64 Testosterone

No. 149 Sex hormone-binding globulin (SHBG)*

No. 60 Luteinizing hormone (LH) , Luteinizing Hormone, LH)

No. 61 Prolactin (Prolactin) (+ additional macroprolactin test if prolactin result is above 700 mU/l)

No. 56 Thyroid Stimulating Hormone (TSH)

No. 11HOMA Insulin resistance index HOMA (HO MA- IR, Homeostasis Model Assessment of Insulin Resistance)

* free testosterone index calculation

General information about the study “Comprehensive hormonal examination for men”

Male reproductive function is supported by the interaction of a number of hormones. An important organ that controls the functions of most of the endocrine glands is the pituitary gland – it is in it that hormones are produced that stimulate the peripheral organs of the endocrine system. Among them, gonadotropins (follicle-stimulating (FSH) and luteinizing (LH) hormones and prolactin) should be noted, which affect the puberty of the male body and the process of spermatogenesis (development of spermatozoa). Another regulatory organ is the testicles, they synthesize androgens, the most important of which is testosterone, which ensures normal reproductive function and libido. Testosterone affects the changes that occur during puberty, controls spermatogenesis, plays a leading role in maintaining the health of a man as a whole.

Disorders of endocrine regulation are considered one of the most common causes of dysfunction of the reproductive system in men. Violations of the hormonal status can provoke environmental factors, bad habits (smoking, alcohol abuse), stress, diseases (diabetes mellitus, obesity, infections, etc.), excessive physical activity or, conversely, physical inactivity, etc. Also, the cause of hormonal imbalance can be taking anabolic steroids is a fairly common phenomenon among athletes, especially professionals. Anabolic steroids contain natural androgens (in particular, testosterone) and synthetic ones, which are structurally related and have a testosterone-like effect. Long-term use or excessive consumption of anabolic steroids is associated with certain health risks and the occurrence of conditions associated with hormonal imbalances, such as gynecomastia (enlargement of the mammary glands in men) and a decrease in the size of the testicles.

Problems caused by changes in hormonal levels can be manifested by a decrease in sexual desire, erectile dysfunction, increased fatigue and irritability, sleep disturbance, a decrease in bone mineral density (osteoporosis), visceral obesity (excess fat deposits in the abdomen), infertility. If a man has a low level of serum testosterone, obesity, arterial hypertension, dyslipidemia, impaired glucose metabolism and insulin resistance can develop – the main components of the metabolic syndrome. In addition, testosterone levels decline with aging, and this decline may be associated with some chronic diseases. In men with a clinical picture and laboratory-proven hypogonadism (insufficient function of the gonads), testosterone therapy may be effective.

Comprehensive examination for men aimed at assessing the level of hormones involved in the regulation of the reproductive system. The profile also includes a test for thyroid stimulating hormone (TSH) – an important link in the regulation of the thyroid gland, and the determination of insulin and glucose levels with the calculation of the insulin resistance index (HOMA).

The specifics of the use of tests profile “Comprehensive hormonal examination for men”

Testosterone – one of the main androgenic hormones – plays a key role in puberty, the development of secondary sexual characteristics, ensuring reproductive and sexual functions in men. In the body, testosterone is synthesized from cholesterol under the stimulatory effect of luteinizing hormone (LH). In the blood, most testosterone is inactive: 60-70% of the hormone is bound to sex hormone-binding globulin (SHBG), 25-38% to albumin (weakly bound testosterone), and only 2% of free testosterone is biologically active. Along with the androgenic effect, testosterone has a powerful anabolic effect on organs (muscles, liver), i.e., it accelerates protein synthesis in them. Low testosterone levels can cause reduced fertility, sexual dysfunction, impaired muscle mass formation and bone mineralization, impaired fat metabolism, and cognitive impairment. The level of the hormone decreases in some diseases and conditions: insulin resistance, metabolic syndrome, vascular complications. The symptoms of testosterone deficiency include the extinction of libido, a decrease in the number of morning erections, a decrease in the size of the testicles, mild body hair growth, gynecomastia (breast enlargement), etc. In some cases, men have a normal level of testosterone, while the concentration of LH increases, which can be considered as subclinical or compensated form of hypogonadism – a syndrome associated with low testosterone levels. Also, the determination of LH is carried out for the differential diagnosis of primary and secondary forms of hypogonadism.

Along with the luteinizing hormone, prolactin also supports male reproductive function, activates anabolic processes, regulates water-salt metabolism (slows down the excretion of water and sodium by the kidneys), and stimulates calcium absorption. Excessive content of prolactin contributes to gynecomastia, decreased sexual desire, weakening of erection.

Thyroid-stimulating hormone is a pituitary hormone that regulates the function of the thyroid gland (TG). The thyroid gland, interconnected with the hypothalamic-pituitary-gonadal axis, has a significant impact on the reproductive system. One of the manifestations of thyroid dysfunction in men is hypogonadism. The combination of the pathology of this organ with androgen deficiency contributes to a decrease in sexual and reproductive functions, and a deterioration in the quality of life. Long-term uncompensated hypothyroidism (the symptoms of which may partially coincide with manifestations of hypogonadism) leads to a slowdown in the maturation of the testicles and impaired spermatogenesis.

Insulin resistance assessment is the most common method for assessing insulin resistance and involves determining the basal (fasting) glucose-to-insulin ratio. The method is used in a set of tests when examining patients with obesity, diabetes, metabolic syndrome, etc. Diabetes mellitus and low testosterone levels often coexist and aggravate each other. This is due to the fact that androgens are involved in the regulation of fat and carbohydrate metabolism. Testosterone levels fall with aging, and this decline may be associated with the development of type 2 diabetes mellitus (DM2), which occurs predominantly in old age.

What is the purpose of the Comprehensive hormonal examination for men?

Test material

See relevant tests.

Method of determination