home Calculators Pituitary gland: what is it and what is its effect on the body? Pituitary hormones: functions and abnormalities

Pituitary gland: what is it and what is its effect on the body? Pituitary hormones: functions and abnormalities

The pituitary gland of the brain is a gland that is the main gland of the endocrine system. The gland produces hormones. She uses her hormones to control various organs person. The functioning of the pituitary gland is controlled by the hypothalamus, a part of the diencephalon, which is located next to the pituitary gland and thalamus. Based on where the pituitary gland is located, one can judge the degree of its importance for normal life person. Any disturbances in the functioning of this gland lead to serious disturbances in the body.

Characteristics of the pituitary gland

A more accurate description of where the pituitary gland is located is the base of the brain, the “sella turcica” (the depression of the skull, in the middle cranial fossa). On both sides of the pituitary gland there are nerves and large vessels, and the optic nerves are also located above it.

The weight of the pituitary gland is very small. This gland in an adult weighs 0.5-0.6 g; after pregnancy and childbirth in women, the pituitary gland increases slightly, sometimes even up to 1.5 g. The dimensions of the pituitary gland correspond to its weight: 1.4 x 1.1 x 0.8 cm.

The pituitary gland has a certain structure. It consists of lobes (anterior, intermediate and posterior) and is connected to the hypothalamus by a small tube. Each lobe of the pituitary gland has its own purpose. The structure of the pituitary gland allows it to perform its functions. Each lobe of the pituitary gland produces its own type of hormone.

Pituitary hormones

Each of the lobes, closely interconnected, is responsible for the production of certain hormones. What the pituitary gland is responsible for will become clear if we analyze in detail the functions of the hormones it produces.

The anterior lobe produces the following hormones:

The posterior lobe of the pituitary gland (neurohypophysis) produces the following hormones:

vasopressin – controls the functioning of the cardiovascular, central nervous systems and kidneys;
Oxytocin plays a huge role in human reproductive function.

The neurohypophysis also produces several other hormones that perform similar functions to those listed (mesotocin, glumitocin, vasotocin, isotocin, asparotocin, valitocin).

The intermediate or middle lobe of the pituitary gland produces the following hormones:

alpha-melanocyte-stimulating and γ-melanocyte-stimulating hormones are responsible for pigmentation and ultraviolet protection;
beta-endorphin is responsible for reducing stress, pain, shock, for the tone of the nervous system, etc.;
met-enkephalin is responsible for the regulation of behavior and pain control;
γ-lipotropic hormone regulates fat metabolism in the body.

Functions of the gland

The functions of the pituitary gland are quite numerous. Any deviations in its work lead to serious complications. The pituitary gland ensures homeostasis in the body, controls all metabolic processes directly or indirectly, through the control of other glands. Control thyroid gland, adrenal glands and gonads are provided by pituitary hormones.

The growth and development of organs and tissues is also carried out by pituitary hormones. Therefore, insufficiency of hormones leads to dwarfism, and excess of hormones provokes too active human growth.

The control of many systems and individual organs also occurs thanks to the pituitary gland (uterine contractility, gastrointestinal tract, lactation, reproductive function, work of cardio-vascular system and etc.).

In addition, pituitary hormones regulate metabolic processes (fat synthesis, etc.). The mental and nervous systems are also dependent on the functioning of the pituitary gland. The perception of stress, pain, and the development of shock depend on the hormonal state.

Any deviations in the production of pituitary hormones lead to serious consequences, irreversible changes in the body. Timely diagnosis and treatment of such disorders is important.

Pituitary gland - main element endocrine system. Pituitary hormones control the functions of many organs. Malfunction of this gland very often becomes the cause of many diseases or abnormalities in the growth and development of the human body.

Description of the pituitary gland

From normal functioning The condition of the organism as a whole depends on this organ. The pituitary gland develops in the fetus already at 4-5 weeks of pregnancy along with the pituitary arteries, which are responsible for the blood supply to this gland.

The pituitary gland is located in the sphenoid bone of the skull and is held in place by a fixing shell. It has oval shape, its size is about 10 mm in length and 12 in width, but may vary slightly. Weight is about 5-7 mg, in women it is more developed than in men. It is believed that this is due to the production of prolactins, which are responsible for the manifestation of maternal instinct.

The pituitary gland produces various hormones and includes an anterior (adenohypophysis) and posterior (neurohypophysis) part. The anterior part of the pituitary gland is the largest and produces large quantity hormones and has more functions, while the back weighs only 20% of the entire organ.

An interesting fact: during self-induced pregnancy (the actual absence of a fetus), a woman’s mammary glands, uterus and abdomen may enlarge, which proves the connection between the pituitary gland and the cerebral cortex.

Hormones of the anterior pituitary gland

The anterior lobe is called the adenohypophysis. It is responsible for body processes such as stress, growth, reproduction, lactation. The hypothalamus controls the activity of the adenohypophysis, and the latter, in turn, regulates the activity of the adrenal glands, liver, thyroid and gonads, bone tissue. A list of pituitary hormones of the anterior lobe and their functions are presented in the table of this article.

The main parts of the adenohypophysis:

distal - has largest size, produces most hormones;
tubular - located in the shell of the distal part, poorly studied;
intermediate part - located between the distal part and the neurohypophysis.

Somatotropin (GH, or growth hormone)

Responsible for growth and development by influencing the long tubular bones of the limbs and enhancing protein synthesis. In the third decade of a person’s life, as well as every subsequent 10 years, its level decreases by 15%. Somatotropin has an immunostimulant effect and can influence carbohydrate metabolism, by increasing blood glucose levels, reduces the risk of fat deposits (in combination with sex hormones and thyroid hormones), and increases muscle mass.

Note: if the child’s growth is slow, tablets or injections containing GH are prescribed. The second option is considered the most effective, because somatotropin is best preserved in the form of a powder, which is convenient to dissolve in liquid and give an injection.

The amount of growth hormone varies throughout the day. It peaks after about two hours of sleep at night, and during the day it peaks every 3-5 hours. Over the period of life, its highest level is achieved during pregnancy in the fetus at 4-6 months - at this time it is a hundred times higher than in an adult.

The secretion of this pituitary hormone is influenced by peptide hormones hypothalamus. You can increase it using physical exercise, sleep, consumption of certain amino acids. With high blood levels fatty acids, somatostatin, glucocorticoids and estradiol, the level of somatotropin decreases.

Excess GH can cause thickened bones, a thickened tongue, acromegaly, and rough facial features. On general condition This is reflected in the body by muscle weakness and pinched nerves. Low somatotropin in children is expressed by retarded growth, sexual and mental development(the appearance of the last two factors is significantly influenced by the underdevelopment of the pituitary gland).

TSH (thyroid stimulating hormone)

TSH controls the production of T3 (thyroxine) and T4 (triiodothyronine). When TSH is high, both of these hormones decrease, and vice versa. TSH norm varies depending on the time of day, age and gender of a person. During pregnancy, its level is quite low in the first trimester and may exceed the norm in the last.

Important: when taking a blood test for TSH, it is necessary to check T3 and T4, otherwise the diagnosis may be erroneous. In addition, tests must be taken at the same time of day.

Causes of low TSH:

trauma and inflammation in the brain;
inflammatory processes, tumors or oncology of the thyroid gland;
incorrectly selected hormonal therapy:
stress.

A simultaneous decrease in TSH, T3 and T4 may signal the presence of a disease such as hypopituitarism, and an increase in the latter may indicate hyperthyroidism.

Causes of high TSH:

thyroid diseases;
pituitary adenoma;
unstable production of thyrotropin;
preeclampsia (in pregnant women);
depressive disorders.

With an increase in all pituitary hormones of this group, primary hypothyroidism can be diagnosed, and with different T3 and T4, the appearance of thyrotropinoma is possible.

ACTH

Adrenocorticotropic hormone controls the degree of activity of the adrenal glands, which produce cortisol, cortisone and adrenocorticosterone. In general, ACTH influences hormones that help cope with stress, control sexual development, reproductive function body.

Advice: before analyzing this pituitary hormone in the blood, you need to refrain from severe physical activity, eating fatty, spicy, smoked foods, alcohol. Blood is drawn in the morning on an empty stomach.

Reasons for increased ACTH:

Addison's disease, Itsenko-Cushing's disease;
presence of a tumor in the pituitary gland;
congenital adrenal insufficiency;
Nelson's syndrome;
ectopic ACTH syndrome;
taking certain medications;
postoperative period.

Reasons for decreased ACTH:

inhibition of the function of the pituitary gland and/or adrenal cortex;
the presence of an adrenal tumor.

Prolactin

Prolactin plays a very big role important role V female body. This pituitary hormone affects sexual development in women, regulates the lactation process (including preventing conception during this period), forms the maternal instinct, and helps maintain progesterone. IN male body it controls the synthesis of testosterone and is involved in the regulation of sexual function, namely spermatogenesis.

Important: a few days before taking a prolactin test, sexual intercourse, visits to baths and saunas, alcohol are prohibited, and it is also advisable to avoid stress. Even slight stress can show this pituitary hormone to be elevated.

Reasons for increased prolactin:

prolactinoma;
anorexia;
hypothyroidism (low production of thyroid hormones);
polycystic ovary syndrome.

A deficiency of this pituitary hormone is caused by tumors or tuberculosis of the pituitary gland itself, as well as head injuries that have a depressing effect on this gland.

Posterior pituitary hormones

The main task of the neurohypophysis is to regulate blood pressure, heart tone, water balance and sexual function.

Oxytocin

It is most significant for women, because stimulates the work of the uterine muscles, controls the lactation process, and is responsible for the manifestation of the maternal instinct. It significantly affects a person’s behavior, his psyche, sexual arousal, and can reduce stress levels and give a feeling of calm. Is a neurotransmitter. In men, it increases potency.

Important! This pituitary hormone can be increased only by relaxing procedures, walks, i.e. actions that improve a person's mood.

Vasopressin

The main function of vasopressin is the body’s water balance, carried out through active work kidney Active growth Depletion of this hormone occurs with large blood loss, low blood pressure, and dehydration. Vasopressin is also able to remove sodium from the blood, saturate body tissues with fluid, and in combination with oxytocin improves brain activity.

Lack of vasopressin leads to dehydration and diabetes mellitus. Its excess is extremely rare and is called Parhon syndrome, the symptoms of which are low blood density and high sodium content. Patients can quickly gain weight, suffer from headaches, nausea, loss of appetite, and general weakness.

Fact: The posterior lobe of the pituitary gland contains a number of other hormones with similar properties: mesotocin, isotocin, vasotocin, valitocin, glumitocin, asparotocin.

Average share

Another name is intermediate. Its value is less than other shares, but it is also capable of secreting hormones. The main ones:

alpha-melanocyte-stimulating - promotes the production of melanin;
beta-endorphin - reduces pain and stress levels;
γ-lipotropic - reduces fat deposits, accelerates the breakdown of fats;
γ-melanocyst-stimulating hormone - an analogue of alpha-melanocyte-stimulating hormone;
met-enkephalin - regulates human behavior and pain.

Conclusion

Many hormones are used in medical practice for treatment various diseases. To monitor your health, it is recommended to get tested once or twice a year. Since it is necessary to know not only the results of the analysis, but also what the pituitary hormones influence, it is best to turn to professionals. Timely correction of hormone levels will reduce the consequences for the body to a minimum.

Endocrine glands, which include the pituitary gland, produce biologically active substances - hormones, which are released directly into the blood and are transported with its current to the organs. Pituitary gland (from Greek.hypophysis- process) regulates the activity of other endocrine glands, influences the processes of reproduction, and participates in the implementation of protective and adaptive reactions of the body. The pituitary gland is part of the system neurohumoral regulation, stimulating or inhibiting the production of tropic hormones corresponding to the hormones of the gonads, adrenal glands and thyroid gland.

The structure and location of the pituitary gland

The pituitary gland has a round shape and weighs about 0.5 g. It is located inside the skull, in a small depression at its base, and is attached to the brain (to the hypothalamus) with the help of a thin stalk - the funnel (Fig. 1). This place is called saddle turcica. It is separated from the cranial cavity by a dense membrane - the sellar diaphragm, through a narrow opening through which a funnel passes. The size of the pituitary gland is judged by the size of the sella turcica on radiographs of the skull.

In the embryo, the pituitary gland develops from different primordia. Therefore, the pituitary gland seems to consist of two fused parts, having various functions and structure. The growth of the pituitary gland stops at the end of puberty. Their production of hormones occurs already at the very early stages development - at the 9-10th week of embryo formation. The formation of the activity of the pituitary gland is associated with the development of the brain. The most important stages are 6-7 years and 10 years, when the production of hormones by the pituitary gland increases significantly.

In accordance with the development of the pituitary gland, from two rudiments it is distinguished, as already indicated, the anterior lobe - adenohypophysis, and the posterior lobe - neurohypophysis. The adenohypophysis is larger, its mass makes up 70-80% of the mass of the entire gland. The smaller neurohypophysis belongs to a part of the brain called the hypothalamus.

Hypothalamic-pituitary

The pituitary gland is included in the neurohumoral regulation system, which works according to the principle feedback. Thus, a lack of hormones in the blood of the sex glands, adrenal glands or thyroid gland stimulates the production of corresponding tropic hormones. And an excess of hormones from these glands in the blood inhibits the production of tropic hormones.

Humoral (carried out through the blood) regulation of body functions is under the direct control of the nervous system and is carried out jointly with it. The hypothalamus occupies a central place in this process. Thanks to close cooperation the pituitary gland and the hypothalamus create a single hypothalamic-pituitary system, which controls the functions of the body. It is in the nuclei of the hypothalamus that substances are produced ( neurohormones), which then enter the pituitary gland and contribute to its production of hormones. Neurohormones enter the anterior pituitary gland through the system blood vessels, in the back - along the processes themselves nerve cells. The pituitary gland, together with the hypothalamus, is the central link of the endocrine system and performs the function of integrating and coordinating the activity of the endocrine glands.

Pituitary hormones

Cells of the anterior pituitary gland produce tropic hormones, which selectively regulate the activity of other endocrine glands and the development of the body as a whole.

Somatotropic hormone(growth hormone) stimulates protein synthesis in organs and tissues and the growth of the body as a whole. For its action, it is necessary to have a sufficient amount of carbohydrates and insulin (pancreatic hormone) in the body. Influenced growth hormone the breakdown of fats and their use in energy metabolism is enhanced.

Gonadotropic hormones stimulate the activity of the gonads. One of them - follicle stimulating hormone(FSH) - promotes the development of follicles in the ovaries and the formation of sperm in the ovaries. Another, luteinizing hormone(LH), is necessary for the release of mature eggs from the follicle (ovulation) and the secretion of female and male sex hormones. In women, FSH and LH regulate the menstrual cycle.

Prolactin promotes the growth of mammary glands and milk secretion, and also stimulates the release of female sex hormones in the ovaries. In addition, he is responsible for the manifestation of parental instinct. Experiments on animals have shown that administering prolactin to males increases their interest in their young, and under certain conditions can cause their mammary glands to secrete milk.

Adrenocorticotropic hormone(ACTH) stimulates the growth of the adrenal cortex and its production of numerous hormones. The secretion of ACTH by the pituitary gland increases under stress.

Thyroid-stimulating hormone(TSH) is necessary for the development and normal functioning of the thyroid gland: it promotes the accumulation of iodine, increases the number of secretory cells and increases their activity. The secretion of TSH by the pituitary gland increases with insufficient levels of thyroid hormones in the blood, as well as with cooling. In the latter case, this leads to increased heat production in the body.

The posterior lobe of the pituitary gland secretes hormones that regulate the tone of vascular smooth muscles ( vasopressin) and uterus ( oxytocin) (Fig. 2). Vasopressin causes contraction of vascular smooth muscles (mainly small arteries) and leads to an increase in blood pressure, regulates reverse suction water in the kidneys, which reduces diuresis and increases urine density (therefore another name for this hormone is antidiuretic hormone). Oxytocin stimulates uterine contractions, especially at the end of pregnancy, and also affects milk secretion. The presence of this hormone in the blood is a prerequisite for the normal course of labor.

Diseases due to disruption of hormone production

Change normal sizes pituitary gland leads to disruption of hormone production and noticeable changes in the state of the body. Hormones enhance or weaken various body functions. Both their deficiency (hypofunction) and excess (hyperfunction) lead to changes in the state of the body.

With hyperfunction of the anterior pituitary gland in childhood increased body growth is observed: the person becomes very tall. In such giants, whose height exceeds 2 m, examination may reveal a pituitary tumor. If the pituitary gland is not active enough during the growth period (hypofunction), then growth retardation occurs and a short person (dwarf) is formed. In such people, skeletal ossification occurs later, the genitals and secondary sexual characteristics are poorly developed, and they do not tolerate infectious and other diseases well.

In an adult, hyperfunction of the anterior lobe of the pituitary gland leads to acromegaly - excessive enlargement of the hands, feet, nose, tongue, facial bones, ears, some organs of the chest and abdominal cavities - lower jaw becomes long and wide, the nose thickens, cheekbones and brow ridges stand out strongly. In addition, with acromegaly, the functions of other endocrine glands, in particular the reproductive and pancreas, are disrupted. With hypofunction of the anterior lobe of the pituitary gland in adults, a metabolic disorder is observed, which leads either to obesity (pituitary obesity) or to sudden weight loss (pituitary cachexia).

Hypofunction of the posterior lobe of the pituitary gland is the cause of diabetes insipidus (diabetes insipidus). In this case, a large amount of urine is released (up to 4 liters per day), due to the inability of the kidneys to concentrate it, and severe thirst occurs.

Hyperprolactinemia syndrome serves as both a manifestation of an isolated hypothalamic-pituitary pathology and...

Clinical picture of the disease... The clinical picture of Itsenko-Cushing's pathology is very characteristic. In those suffering from BIC (Cushing's disease)...

Hyperprolactinemia (prolactinomas) most often occurs in young women. The symptom is the appearance...

Pituitary gland - what is it?
This concept refers to one of the smallest glands that plays...

The pituitary gland (putuitary gland) is located in a small depression at the base of the brain, just below...

Tumors of this gland are often called pituitary adenomas. In fact, these phenomena can have many faces...

The pituitary gland is endocrine gland, which is located in the brain. Actually human...

So, any disturbances in the functioning of this gland are a direct path to the development of numerous very dangerous diseases. So, for example, a lack of pituitary hormones causes the development of diseases such as: hypothyroidism, dwarfism, diabetes insipidus, hypopituitarism and some others. As for dwarfism, it is noted only if a lack of hormones from this gland is observed in childhood. I would like to give a definition to such a condition as hypopituatarism. Hypopituatarism is a deficiency of not one, but several hormones, which leads to disruption of the development of the child’s reproductive system.

Quite often, doctors note an excess of such hormones. In this case, it makes itself known hyperprolactinemia, gigantism, acromegaly, Cushing's disease, osteoporosis And so on and so forth. In fact, there are plenty of reasons for the pituitary gland to malfunction. These include traumatic brain injuries, and radiation, and hemorrhage, and meningitis, and reception pharmaceuticals , and many others.
By the way, to normalize the functioning of this gland, you can use the help of special dietary supplements (dietary supplements).

The pathology rarely occurs before the age of 12 or after 60 years. IN adolescence Cushing's disease mainly develops during puberty.

The clinical picture of Itsenko-Cushing's pathology is very characteristic. In those suffering from BIC (Cushing's disease), body weight increases and is redistributed adipose tissue- fat is concentrated in the shoulder girdle, supraclavicular areas, and in the cervical region of the spine. At the same time, thinning of the arms and legs occurs due to loss of adipose tissue and muscle atrophy. The face takes on a rounded shape, the cheeks turn reddish, trophic transformations of the dermis are recorded with the appearance of difficult-to-heal ulcers, dryness and high exfoliation. On the hips, chest, shoulders, and abdomen, certain skin stretches appear in the form of stripes with a red-violet tint. The result is high fragility of the capillaries; with minor bruises, hematomas appear.

At the same time, excessive pigmentation of the epidermis occurs in areas of friction (neck, elbows, armpits). In women, high hirsutism is often recorded on the face (mustache, beard) and in the chest area.

One of the first manifestations of NIR is sexual disorders in the form of irregular menstruation, decreased potency.

One of the most dangerous complications Itsenko-Cushing's disease is caused by damage to the cardiovascular system, in the form of progression of blood pressure with disruptions in metabolism in the heart. Different muscles undergo atrophy with characteristic clinical pictures(for example, with atrophy of the peritoneal muscles, the size of the abdomen increases). Electrolyte disruptions progress, hormonal in nature (hormonally active and passive);
by volume (microadenomas, small, medium, large and extra-large);
topographic-anatomical division (endosellar, endoextrasellar with slight and severe tumor contamination);
histological division and others.

Pituitary adenoma synthesizes mainly 6 hormones, therefore, depending on which cells the adenoma developed from, that hormone will be synthesized in large quantities, which will provoke the appearance of a certain pathology (Itsenko-Cushing pathology, acromegaly, hyperprolactinemia, etc.).

Hyperprolactinemia (prolactinomas) most often occurs in young women. The symptom is the appearance of lactoreamenorrhea syndrome (the release of colostrum from the mammary glands with irregular menstruation). In addition to amenorrhea, infertility may occur due to constant (or disrupted) menstruation without ovulation.

In women, prolactinomas are usually detected in the first stages of development, since women have more obvious manifestations- disruptions in menstruation, which gives an early warning signal.

Hyperprolactinemia is one of the most important factors in sexual dysfunction in men. Of the pathologies that provoke hyperprolactinemia in men, prolactinomas come first, followed by other tumors of the chiasmalosellar region, which change the shape of the pituitary stalk and provoke hyperprolactinemia - pseudoprolactinomas.

In a situation where the factor of hyperprolactinemia in men is a large pituitary adenoma, the manifestations of the pathology may predominantly include signs of loss of pituitary tropic hormones.

Registration of hyperprolactinemia in men is complicated by the fact that the corresponding manifestations (infertility, decreased sexual desire and weakening of potency) are rarely taken as manifestations endocrine pathologies. As a rule, pathology is discovered late, since in men the manifestation of weakened potency is more subjective.

Acromegaly is a dangerous neuroendocrine pathology that progresses as a consequence of constant excess synthesis of somatotropic hormone. The main factor for acromegaly is somatotropic pituitary adenoma, but it can also be caused by oncological diseases pancreas, lungs, mediastinum and other regions, as well as inherited pathologies.

This pathology manifests itself through disproportionate growth of the skeleton, cartilage, soft tissues, and organs, which occurs in adults with completed physiological development. At the age of up to 18 years, with continued physiological development, excessive production of somatotropic hormone provokes the progression of gigantism, which is characterized by proportional growth of bone tissue in length, ultimately leading to greatly increased human growth. If this person does not receive appropriate treatment, then upon completion of puberty he will have all the standard manifestations of acromegaly.

This effect on the body provokes the appearance various complications, which in turn leads to severe disability, reduced life expectancy, high mortality, the likelihood of which, without appropriate therapy, is very high.

Those suffering from acromegaly experience skeletal injury in the form of enlargement of size upper jaw, expansion of spaces between teeth, thickening of the frontal bone, arthritis of bone tissue, Scheuermann-Mau disease, osteoporosis, excessive growth of the limbs.

Nervous and endocrine system humans have not yet been fully studied. What do they have in common? What significance do they have for the human body, and what functions do they perform?

What is the pituitary gland?

The pituitary gland is located in a bone formation - the sella turcica, consists of neurons and endocrine cells, coordinates the interaction of these two critical systems body. Pituitary hormones are produced under the influence of the nervous system; they unite all the glands internal secretion into one common system.

In its structure, the pituitary gland consists of the adenohypophysis and the neurohypophysis. There is also middle part pituitary gland, but due to its similar structure and functions it is usually referred to as the adenohypophysis. Percentage the neurohypophysis and the adenohypophysis are not the same; the majority of the gland is the adenohypophysis (according to some data - up to 80%).

The pituitary gland is a small gland, shaped like a legume, it is located in the sella turcica (a bone formation of the skull), its weight hardly exceeds 0.5 g. It belongs to the central glands.

Pituitary hormones also differ:

adenohypophysis hormones are secreted in the gland and released into the blood;
hormones of the posterior lobe of the pituitary gland are only stored in it and released into the blood as needed;
neurohypophysis hormones are produced by neurosecretory nuclei in the hypothalamus, and then sent to the pituitary gland along nerve fibers, where they are stored until they are demanded by other glands;

Hypothalamus - combines the functions of the endocrine and nervous systems. The hormones of the hypothalamus and pituitary gland are closely related.

Functions

Pituitary hormones contribute to their release by the thyroid gland, adrenal cortex, and gonads.

Adenopituitary hormones are tropic substances (with the exception of β-endorphin and met-enkephalin), biologically active substances whose action is directed to tissues and cells or stimulates other endocrine glands to achieve the desired result. Hormones of the anterior pituitary gland include:

The posterior lobe of the pituitary gland produces vasopressin and oxytocin.

It is hardly possible to overestimate the importance of these biological active substances for the body, they are responsible for most vital functions.

Brief characteristics of anterior lobe hormones

Thyroid-stimulating

Thyroid-stimulating hormone is a protein that consists of two structures α and β. Only β has activity. The main function of thyrotropin is to stimulate the thyroid gland to secrete thyroxine, triiodothyronine and calcitonin in adequate quantities. Thyroid-stimulating hormone fluctuates significantly throughout the day. Maximum concentration thyroid-stimulating hormone observed at 2-3 am, minimum at 17-19 hours. As we age, the secretion of thyroid-stimulating hormone is disrupted and it becomes less abundant.

However, an excess of thyroid-stimulating hormone leads to disruption of the function and structure of the thyroid gland; its tissue is gradually mixed with colloidal tissue. Similar changes are detected during ultrasound diagnosis of the thyroid gland.

Adrenocorticotropic

Adrenocorticotropic hormone is the main stimulator of the adrenal cortex. Under its influence, the bulk of corticosteroids are produced, and it also affects the secretion of mineralocorticoids, estrogen and progesterone. It affects the human or animal body indirectly, affecting the metabolic processes that regulate corticosteroids. Another of its functions is participation in the secretion of pigments, which often leads to the formation age spots on the skin. Adrenocorticotropic hubbub is the same in humans and animals.

Somatropin

Somattropin is one of the the most important factors growth. Violation of the secretion of delivery or sensitivity to it in childhood leads to irreparable consequences. He is responsible for:

skeletal growth, especially the growth of long bones;
deposition of adipose tissue and its distribution in the body;
protein formation and metabolism;
muscle growth and strength.

Its function is that it participates in metabolic processes and affects insulin metabolism and the pancreatic cells themselves.

Gonadotropins

Gonadotropic hormones of the pituitary gland include follicle-stimulating and luteinizing hormones. They are made up of amino acids and are proteins in structure. Their main function is to ensure full reproductive function in men and women. FLG is responsible for the maturation of follicles in women and sperm in men. Luteinizing hormone promotes the rupture of follicles, the release of the egg, the formation corpus luteum in women, and stimulates androgen secretion in men.

Gonadotropin levels in men and women reproductive age not the same. In men it is approximately constant, but in the fair sex it varies significantly depending on the phase menstrual cycle. In the first phase of the cycle, follicle-stimulating hormone dominates, LH is minimal during this period, and, conversely, in the second it is activated. Their action is continuously interconnected, they complement each other.

Prolactin

Prolactin also plays a huge role in reproductive function. It is responsible for the subsequent development of the mammary glands and lactation, the expression of secondary sexual characteristics, the deposition of fat in the body, the maturation of the corpus luteum, growth and development internal organs, functions of skin appendages.

The action of prolactin is twofold. On the one hand, it is he who is considered responsible for the formation of the maternal instinct, the behavior of a pregnant woman and a young mother. On the other hand, excess prolactin leads to infertility. During pregnancy and lactation maximum effect lactogenic hormone is observed in combination with somatotropin and placental lactogen. Their interaction ensures the full growth and development of the fetus and the health of the pregnant woman herself.

Melanocyte-stimulating

Melanocyte-stimulating hormone is responsible for the production of pigment in skin cells. It is also believed that it is he who is responsible for the inadequate growth of melanocytes with their subsequent degeneration into malignant formations.

Hormones produced by the posterior lobe

Oxytocin and vasopressin

The posterior pituitary hormones oxytocin and vasopressin are completely different in their functions. Vasopressin is responsible for water-salt balance body, its action is aimed at the tubules of the nephrons of the kidneys. It stimulates the permeability of the wall to water, thereby controlling diuresis and circulating blood volume. When the secretion of antidiuretic hormone is disrupted, such a serious disease as diabetes insipidus develops.

Oxytocin has important for pregnant and lactating women, as it stimulates labor, as well as milk excretion. But the point of application and the effect of oxytocin in a nursing woman and a pregnant woman are different. On later During pregnancy, the endometrium of the uterus becomes more sensitive to the effects of oxytocin; its secretion during this period increases significantly and continues to increase until childbirth under the influence of prolactin. Contractions of the uterus promote the advancement of the fetus to the cervix, which provokes labor and the movement of the child along the birth canal. During lactation, oxytocin is produced when the baby sucks at the breast, this stimulates milk production.

It is very important for a young mother to put her baby to the breast early. The more often and more the baby tries to suckle, the faster the mother’s lactation will normalize.