Hormones of the female reproductive glands. The structure and function of the male reproductive glands. How testosterone is produced

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Male sex glands

The sex glands (sometimes called gonads) are the ovaries in women and the testes in men. The two testicles are located inside the scrotum in the anterior pelvic region. Their main function is the production of sperm, which are secreted through the penis.

Male genital tract

Location and structure

The testicles are the primary sex organs of a man, located in the testes.

Functions

The testicles are responsible for the production of sperm and semen, but they also contain special cells with endocrine function. They produce male sex hormones called androgens, of which testosterone is the main hormone.

Testosterone is responsible for:
... the growth and development of male genital organs and the maintenance of their adult size;

... an increase in the larynx (and, as a result, voice changes);
... increased growth of bones and muscles;
... male sexual arousal.

How testosterone is produced

Testosterone is produced by the action of hormones in the hypothalamus and the anterior pituitary gland. Testosterone levels are regulated by negative feedback.

Female sex glands

The ovaries are a woman's primary reproductive organs, located in the lower abdomen along the sides of the uterus. They produce eggs for reproduction, but also other systems - the ovarian follicles and the corpus luteum - that have endocrine functions related to the body's reproductive activity.

Functions

Ovarian follicles secrete the hormone estrogen, which is responsible for:
... the maturation of the female genital (reproductive) organs, such as the uterus and vagina;
... breast development;
... the growth and distribution of body hair;
... distribution of fat on the thighs, legs and chest.

The corpus luteum also secretes some estrogen, but its main hormone is progesterone, which causes the lining tissue of the uterus to thicken to prepare the body for pregnancy. Both estrogen and progesterone are responsible for the changes that occur during the menstrual cycle.

How estrogen and progesterone are produced

Like testosterone, estrogen and progesterone are secreted by hormones from the hypothalamus and pituitary gland. Estrogen and progesterone levels are regulated by negative feedback.

Female genital tract

Pituitary control of the ovulation cycle

The ovaries are under the control of the anterior pituitary gland. Under the influence of estrogen produced by the ovarian follicle, the pituitary gland produces follicle-stimulating hormone (prolan A, FSH) and luteinizing hormone (prolan B, LH). These hormones cause the follicle to mature and release an egg during ovulation. The remainder of the follicle forms the corpus luteum, which produces progesterone. If the egg is not fertilized, progesterone levels drop and menstruation occurs.

Before puberty, the amount of male and female hormones in boys and girls is about the same. With the onset of puberty, the ovaries produce several times more female sex hormones, and the testes - several times more male sex hormones.

Male sex hormones - androgens (androsterone, testosterone, etc.) are produced in the tissues of the testes. Testosterone regulates the process of spermatogenesis, the development of secondary sexual characteristics, affects the level of protein and carbohydrate metabolism.

Female sex hormones - estrogens (estrol, estriol, estradiol) are produced in the ovaries. They participate in the regulation of puberty and the development of secondary sexual characteristics in girls, regulate the menstrual cycle, and when pregnancy occurs, they regulate its normal course. In the ovaries, a corpus luteum is formed in the place of a bursting follicle (Graaf's vesicle). In the corpus luteum, the hormone progesterone is produced, which prepares the uterine lining for implantation of a fertilized egg, stimulates the development of the mammary glands and the muscular layer of the uterus, and regulates the normal course of pregnancy in its initial stages. During pregnancy, the placenta also produces female sex hormones that regulate the course of pregnancy and childbirth.

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See what "Sex glands" are in other dictionaries:

Modern encyclopedia

- (gonads) organs that form sex cells (eggs and sperm) in animals and humans, as well as produce sex hormones. Male sex glands, testes, female ovaries; mixed sex glands are hermaphroditic (in some worms, ... ... Big Encyclopedic Dictionary

Sex glands- (gonads), organs that form sex cells (eggs and sperm) in animals and humans, as well as produce sex hormones. Male sex glands, testes, female ovaries; mixed sex glands are hermaphroditic (in some worms, ... ... Illustrated Encyclopedic Dictionary

GENITAL GLANDS- GENITAL GLANDS, or gonads, glands that produce sex cells (generative function of the pancreas) and sex hormones (endocrine function of the pancreas). (Comparative anatomy and embryology of the Item. See. Genitourinary organs.) Male sex glands are called ... ... Great medical encyclopedia

- (synonym - gonads), organs that form sex cells (see Gametes) and sex hormones. They are an integral part of the genitals. They perform mixed functions, since they produce products not only external (potential ... ... Sexological encyclopedia

- (gonads), organs that form sex cells (eggs and sperm) in animals and humans, as well as produce sex hormones. Male sex glands, testes, female ovaries; mixed sex glands are hermaphroditic (in some worms, ... ... encyclopedic Dictionary

Human, organs that form sex cells (gametes) and produce sex hormones. Form the sex of an individual, sexual instincts and behavior, etc. Male sex glands (testicles) form sperm and hormones that stimulate development and function ... ... Biological encyclopedic dictionary

Gonads, organs that form sex cells (eggs and sperm) in animals and humans. P. f. higher animals secrete sex hormones into the bloodstream. Intrasecretory function of the Item. regulated by gonadotropic hormones (See Gonadotropic ... ... Great Soviet Encyclopedia

- (gonads), organs that form sex cells (eggs and sperm) in animals and humans, as well as produce sex hormones. Husband. P. f. testes, female ovaries; mixed Item. hermaphroditic (in some worms, molluscs, etc.) ... Natural science. encyclopedic Dictionary

GENITAL GLANDS- the organs in which the germ cells are formed (in women, these are the ovaries, which produce eggs, and in men, the testes, which produce sperm), as well as sex hormones ... Encyclopedic Dictionary of Psychology and Pedagogy

Books

Physiology textbook, Bykov K.M., Vladimirov G.E., Delov V.E., The publication is a textbook for students of medical institutes, which determines its composition and selection of material. As the authors write in the Preface, this edition of the textbook is more ... Category: Human Anatomy and Physiology Publisher: State Publishing House of Medical Literature,
A work in black (MP3 audiobook on 2 CDs), Gustav Meyrink, "Let, from the point of view of intellect and high spirituality, the later novels of Gustav Meyrink are more significant, opening such abysses from which breathtaking, but these stories, ... Category: Classical and contemporary prose Publisher: Bibliophonics, audiobook

Most of the circulating testosterone (60%) is tightly bound in the blood to sex hormone binding globulin (SHBG). Free and albumin-bound testosterone can enter the cells of the body, in light of which this part of testosterone is called biologically available. Despite binding to SHBG, testosterone has a short half-life of 10 minutes. Testosterone is metabolized primarily by the liver. However, testosterone metabolites make up only 20-30% of urine 17-ketosteroids.

SHBG is a large glycoprotein produced by the liver. The production of SHBG by the liver depends on many metabolic factors:

sex steroids actively modulate the synthesis of SHBG - estrogens stimulate it, while androgens suppress, which causes a higher concentration of SHBG in women;
in patients with liver cirrhosis, the level of estrogen in the blood remains normal, and testosterone decreases, which leads to an increase in the level of SHBG in such patients;
reduced concentration of T4 or T, reduces the level of SHBG, while against the background of thyrotoxicosis, the level of SHBG increases;
the concentration of SHBG is reduced in obesity and acromegaly, which is due to the influence of hyperinsulinemia.

Factors affecting the concentration of sex hormone binding globulin

Conversion of testosterone to 17β-estradiol and dihydrotestosterone (DHT)... The daily synthesis of testosterone is 5-7 mg, or 5000-7000 mcg. In healthy men, up to 40 μg of 17β-estradiol is formed, and 3/4 of this amount is formed in peripheral tissues by aromatization of testosterone with the enzyme aromatase, and the remaining 10 μg are secreted directly by testicles (Leydig cells). The greatest amount of aromatase is found in adipose tissue, therefore, the higher the degree of obesity, the more intense the synthesis of estradiol.

Estradiol metabolism in men:

daily production 35-45 mcg;
biologically active 2-3% of estradiol, the rest is associated with SHBG;
sources of circulating estradiol:

formation from testosterone by aromatization at the periphery - 60%;
secretion by testicles - 20%;
peripheral conversion from estrone - 20%.

The main part of DHT (up to 350 μg) is formed by direct transformation of testosterone under the action of 5α-reductase. In humans, two isoenzymes of 5-reductase have been isolated. Type 1 is localized mainly in the skin, liver and testicles, while type II is located in reproductive tissues, genital skin and epididymis.

Binding to androgen receptors... Androgen receptor - a polypeptide (910 amino acids), like other steroid and thyroid receptors, refers to DNA-binding proteins. The same receptors bind testosterone and DHT.

Regulation of the function of the male genital glands

The function of the testicles is regulated by closed feedback systems, in which six main components are distinguished:

extrahypothalamic parts of the central nervous system;
hypothalamus;
adenohypophysis;
testicles;
target organs regulated by male sex hormones;
transport system for male sex hormones and their metabolism.

Extrahypothalamic regulation of the central nervous system... Extrahypothalamic parts of the brain have both a stimulating and a suppressive effect on the reproductive function. In the midbrain, cells contain biogenic amines, norepinephrine (HA) and serotonin (5-hydroxytryptamine; 5-HT), as well as neurotransmitters that are closely associated with many parts of the hypothalamus, including the preoptic, anterior and mediobasal zones, where neurons that produce GnRH are located ...

Hypothalamic regulation

Pulsing GnRH secretion. The hypothalamus serves as an integrating center for GnRH regulation. GnRH is a decapeptide that is secreted into the portal system of the pituitary gland at regular intervals - the peak of secretion is every 90-120 minutes. The half-life of GnRH is 5-10 minutes, and it practically does not enter the systemic circulation, therefore, its content in the blood is not examined. The selectivity of stimulating the secretion of gonadotropins LH and FSH depends on the frequency of the pulsatile secretion of GnRH. The “hypothalamic biorhythm generator” localized in the arcuate nucleus regulates the secretion of GnRH. At the same time, each individual neuron secretes GnRH not constantly, but periodically, which probably provides the total pulsating nature of GnRH secretion under the synchronizing influence of the “hypothalamic biorhythm generator”. The pulsating secretion of GnRH also determines the pulsating rhythm of the secretion of hormones of the glands regulated by it (LH, FSH, androgens, inhibin). Previously, it was assumed that there are releasing hormones for both LH and FSH, but currently the majority share the point of view that only GnRH regulates the secretion of both LH and FSH, and the degree of influence on LH and FSH depends on the rhythm of GnRH secretion: high frequency decreases the secretion of both LH and FSH; low frequency stimulates FSH secretion to a greater extent than LH; administration of GnRH at a constant rate suppresses the secretion of both pituitary gonadotropins.
Regulation of GnRH. The synthesis and secretion of GnRH is regulated by the extrahypothalamic parts of the central nervous system, the concentration in the blood of androgens, peptide hormones, such as prolactin, activin, inhibin and leptin. Local modulation of GnRH secretion is carried out by neuropeptides, catecholamines, indolamines, NO, dopamine, neuropeptide Y, VIN and CRH.

The hypothalamic peptide kisspeptin in men stimulates a rapid increase in LH secretion. More recently, hypothalamic GnRH secretion has been shown to be mediated by kissneurons, which produce kisspeptin, which stimulates the kiss1 receptor. Kisspeptin neurons also mediate the feedback of sex hormones to the hypothalamus.

The introduction of lepitin increases the content of kiss1 in messenger RNA of hypothalamic cells, as well as the secretion of LH and testosterone. Therefore, Kisspeptin can be an intermediate link in the implementation of leptin stimulation of GnRH secretion.

Prolactin suppresses the secretion of GnRH, which is manifested by hypogonadism in patients with hyperprolactinemia.

Pituitary regulation. The gonadotrophins LH and FSH are synthesized by gonadotrophs of the adenohypophysis and are secreted spike-like in response to spike-like secretion of GnRH. However, since the rate of elimination of gonadotropins is lower than that of GnRH, the peaks of gonadotropin secretion are less pronounced. LH and FSH are large glycoproteins.

LH binds to specific membrane receptors in Leydig cells, which triggers a chain of G-protein-mediated reactions that stimulate testosterone synthesis in the testes.

FSH binds to receptors on Sertoli cells, stimulating the formation of a number of specific proteins in them, including androgen-binding protein, inhibin, activin, plasminogen activator, γ-glutamyl transpeptidase, and protein kinase inhibitor. FSH in conjunction with testosterone produced by Leydig cells and activin synergistically stimulate spermatogenesis and suppress the apoptosis of germ cells.

Regulation of the secretion of gonadotropins... As noted above, the secretion of gonadotropins is regulated by the pulsatile secretion of GnRH.

Regulatory effects of inflammatory cytokines.

Biological action of testosterone and its metabolites

Testosterone has a direct effect on the body or indirectly, through its two main metabolites - DHT and 17β-estradiol.

There are three stages of life, in which testosterone has a different, and key, effect on the body. Lack of testosterone or 5a-reductase, which converts testosterone to DHT, leads to the development of ambivalent genitals.

In the absence of the enzyme 5α-reductase, a symptom such as a micropenis appears. DHT is essential for the growth and development of the prostate gland, where its concentration is 10 times higher than testosterone. In principle, the actions of testosterone and DHT are topographically dependent: testosterone affects beard growth, and hair growth in the armpits and pubis is DHT-dependent. DHT inhibits the growth of hair on the scalp, which causes the characteristic baldness in some men. Testosterone stimulates erythropoiesis through two mechanisms:

stimulating renal and extrarenal formation of erythropoietin;
having a direct effect on the bone marrow.

With a deficiency of the aromatase enzyme, osteoporosis develops, as the content of estradiol decreases. Estradiol is also required to close the areas of epiphysial growth.

Recently, there have been data on the effect of testosterone on metabolism:

increases insulin sensitivity and, accordingly, glucose tolerance, stimulates mitochondrial genes for oxidative phosphorylation;
increases the expression of regulatory enzymes of glycolysis and glucose transporter GLUT4;
the effect of testosterone on lipids is manifested after the end of puberty: the concentration of high-density lipoproteins decreases, and triglycerides and low-density lipoproteins - increases;
in the prepubertal period, there are no sex differences in lipid metabolism.

Testosterone has a vasodilating effect, and it is endothelially independent, exerting a direct effect on vascular smooth muscle. Estradiol also has a vasodilating effect through nitric oxide (II).

Testosterone has an important psychotropic effect on the brain, increasing mood (drive), motivation, aggressiveness and libido. It also affects cognitive functions, in particular, improves spatial orientation and mathematical ability. However, testosterone levels are negatively correlated with ease of verbal function.

Biological effects of testosterone and dihydrotestosterone

Testosterone	DHT
Stimulates beard growth. A deficiency leads to erectile dysfunction	Provides intrauterine development of male genital organs
Increases libido. Provides normal penile architectonics	Causes baldness
Stimulates the development of muscle tissue and its strength	Stimulates the growth and development of the prostate gland
Stimulates erythropoiesis
Increases insulin sensitivity
Increases glucose tolerance
Increases the expression of glycolysis regulatory enzymes
Increases the expression of the glucose transporter GLUT4
Has a vasodilating effect
Improves mood (drive)
Improves brain function, particularly short-term memory, and enhances math ability
Testosterone levels negatively correlate with verbal function

In puberty, testosterone and DHT affect the growth of the scrotum, penis and ensure the functional unity of these structures, and they also stimulate:

ambisexual hair growth;
sexual growth of hair (beard, mustache, chest, abdomen and back);
activity of the sebaceous glands (acne).

Testosterone and DHT stimulate the growth of skeletal muscle and larynx, which in the latter case is manifested in a low voice in men.

Testosterone and its metabolites (DHT and estradiol) stimulate the growth of epiphyseal cartilage plates, cause rapid growth at puberty, promote the closure of growth zones of the pineal gland, increase bone mass, stimulate hematopoiesis, prostate growth, libido, change in a characteristic way social behavior, increase aggressiveness.

Estradiol:

provides pubertal growth;
maintains bone density;
regulates the secretion of gonadotropins.

Phases of the functional formation of the hypothalamo-pituitary-gonadal system

In a male fetus, the concentration of gonadotropins and testosterone in the blood begins to increase by the end of the 2nd month of gestation, rapidly increasing to a maximum, which is maintained until late pregnancy; the concentration of testosterone in newborn boys is only slightly higher than that observed in girls.

Soon after childbirth, in boys, LH, FSH and testosterone concentrations rise again and remain at the achieved level for about 3 months, but then gradually decline to very low levels by the end of the first year of life. These low levels of gonadotropins and testosterone persist until puberty.

In the prepubertal period, the secretion of GnRH increases in amplitude and frequency in the morning hours before awakening, which is accompanied by an increase in the secretion of LH, FSH and testosterone in the morning hours. With the development of puberty, the duration of the peak secretion of gonadotropins and testosterone increases until, at the end of puberty, the peaks of secretion become regular throughout the day.

During puberty, the sensitivity of gonadotropins to the stimulating effect of GnRH is also restored.

After the onset of puberty, the concentrations of gonadotropins and testosterone increase, reaching the values of an adult man by the age of 17.

Stages of puberty in boys (according to Tanner)

Stages of development of the genital organs	Pubic hair growth stages
Stage 1... Prepubertal. Testicles, scrotum, and penis are approximately the same size and proportion as in early childhood	Stage 1... Prepubertal. The growth of only vellus hair is noticeable, which is not more pronounced than on the front wall of the abdomen, i.e. pubic hair is absent
Stage 2... The scrotum and testicles enlarge, the texture of the skin of the scrotum changes, it acquires a reddish tint	Stage 2... Growth of long, slightly pigmented, sparse, vellus, straight or slightly curly hair around the base of the penis
Stage 3... The growth of the penis occurs, first mainly in length and to a lesser extent in diameter. Further growth of the scrotum and testicles is also noted.	Stage 3... Hair becomes much darker, coarser, more curly. Growth of thin hair at the suprapubic articulation
Stage 4... The penis increases even more in length and in diameter, the glans of the penis develops. The testicles and scrotum are enlarged, the skin of the scrotum darkens	Stage 4... Full pubic hair growth, as in an adult, but the covered area is noticeably less than in most adults.
Stage 5... The full development of the genitals, both in size and shape. After reaching the 5th stage of development, further growth of the genitals does not occur	Stage 5... Pubic hair, both in quality and type, corresponds to the adult period, distributed in the form of a triangle turned upside down. Hair growth is also noted on the inner surface of the legs, but not along the white line of the abdomen and does not extend over the base of the triangle of pubic hair growth. In most men, hair growth over the pubis develops further with age.

In the pre-pubertal period, the level of gonadotropins and gonadal steroids is low. At the same time, under the influence of ACTH, the secretion of adrenal androgens begins to increase in boys from the age of 7-8, i.e. This phenomenon is called adrenarche. The growth spurt observed before puberty and sometimes the appearance of axillary and pubic hair are associated with the action of adrenal androgens.

The growth of pubic hair is caused by androgens in the testicles and adrenal glands. Hair growth on the face also increases: growth extends to the middle of the lower lip, to the lateral and lower surface of the chin. The first stage of facial hair growth coincides with the 3rd stage of pubic hair growth (average age 14.5 years), and the last stage - with the completion of the 5th stage of pubic hair and the 5th stage of development of the genitals. Hair in the perianal zone appears a little earlier than in the armpits. At the end and after puberty, the hair growth zone extends from the pubic region upwards, taking on a diamond shape.

The first sign of the onset of puberty is usually an increase in the maximum diameter of the testicles (excluding the epididymis) more than 2.5 cm. In maturing Sertoli cells, mitosis stops, and they differentiate into mature cells. Under the influence of LH, the number of Leydig cells in the testicles also increases.

Spermatozoa in morning urine (spermarch) appear at the chronological age of 13.5 years or at the corresponding bone age at 3-4 stages of genital development and pubic hair growth at 2-4 stages. When puberty develops earlier or later, the age of onset of the spermarch changes accordingly. Thus, the reproductive function in boys develops before the onset of physical and, naturally, psychological maturity.

Puberty Acceleration (Leap) growth occurs under multilateral endocrine control, in which the leading role is played by growth hormone and sex hormones; with a lack of one or both of them, the pubertal growth spurt decreases or does not occur at all. By enhancing the secretion of STH, sex hormones indirectly stimulate the synthesis of IGF-1 and, in addition, directly activate the formation of IGF-1 in cartilage. From the beginning of puberty, the growth rate of the legs outstrips the growth rate of the trunk, but during the growth spurt, these rates level out. The distal parts of the limbs (feet and hands) begin to grow before the growth of the proximal parts, so the rapid increase in shoe size is the first harbinger of puberty growth. On average, during puberty, boys grow by 28 cm, and the later puberty begins, the higher the final growth is (due to the longer puberty).

At puberty, the larynx increases, the vocal cords thicken and lengthen, which is accompanied at about 13 years of age by a fragile voice and a decrease in its timbre, the formation of a male timbre is completed by the age of 15. Due to the anabolic action of androgens, the mass of muscles (especially androgen-sensitive muscles of the chest and shoulder girdle), connective tissue, bones increases, and the density of bone tissue increases. The lymphoid tissue reaches its maximum mass by the age of 12, and after that the mass decreases with the progression of puberty.

The sex glands are organs that take part in the formation of germ cells. They are part of both the female and male reproductive systems and belong to the mixed secretion glands. These secretory organs produce hormones. When released into the bloodstream, they ensure the normal functioning of the body and genitals in particular. They also produce cells, without which conception is impossible: sperm and eggs.

When the genitals are formed

The development of the reproductive system of the unborn child occurs at about 4 or 5 weeks of gestation. In this case, the sex glands are also formed. At first, the embryo is bisexual, that is, organs develop in the same way in boys as in girls. Belonging to a particular gender looms closer to 12 weeks. The process depends entirely on the Y chromosome. The male sex glands begin to develop from the mesoderm. The seminiferous tubules, excretory ducts of the glands are formed. At 8 months, the testicles descend into the scrotum. After 32 weeks, there is little ovarian hormonal activity in girls. It lasts until the end of pregnancy and is the norm. Further organ development ends during puberty.

These organs in women include the ovaries. Their weight is about 8 grams.

These paired sex glands are located in the small pelvis and have a bluish color. The structure of the organ is heterogeneous, the surface consists of cubic epithelium. The cortical substance is located deeper. Globular sacs can be observed in it. This is the follicle in which the egg cell develops. After the process of its maturation, the membrane bursts, the female reproductive cell through the fallopian tubes enters the uterine cavity. This is how the ovulation process takes place. In place of the follicle that burst, a corpus luteum is formed. If fertilization does not occur, it turns whitish, and then disappears altogether. The female sex glands secrete the following hormones: estrogens, progesterone.

The hormone estrogen: functions

Estrogen means a group of hormones: estradiol, estriol, estrone. They all play an important role in the body. First of all, they are responsible for the normal course of the menstrual cycle. In addition, they directly contribute to fertilization, the release of the egg into the uterus. The hormones estrogens, which are produced by the gonads, affect the condition of the skin, the type of hair growth (female), the work of the sebaceous secretion organs, and also take part in water-salt metabolism. Stimulating bone formation is another function they perform. It is the lack of estrogen production during menopause that contributes to frequent fractures and the development of osteoporosis. With a small amount of the hormone during puberty, a cycle failure, slow development of the mammary glands and other genital organs can be observed. Its increased content is characterized by irritability, weight gain, skin and hair problems.

Progesterone, its meaning

The second hormone that the female sex glands produce, namely the corpus luteum, is progesterone. It directly affects the process of conception, and also helps to maintain and bear a child. With its help, the egg is able to gain a foothold in the uterus. Also, progesterone stops the menstrual cycle during pregnancy. With its insufficient amount, you can observe vaginal bleeding, irregularities in the course of menstruation, sudden mood swings, inflammatory processes in the organs of the reproductive system. It is also important that one of the causes of infertility is the low content of this hormone. An excess of progesterone indicates the presence of neoplasms (although its increased content during pregnancy is the norm). With an increased production of this hormone, frequent depression can be observed (since it directly affects the emotionality of a woman), sexual desire decreases, headaches and weight gain are not uncommon.

The testes in men are the organ for the secretion of sex hormones. It is in them that spermatozoa are formed and specific substances are produced.

The male sex glands perform the following functions: preparation for the process of conception, the manifestation of sexual desire, the development of secondary sexual characteristics. Intensive testicular growth is observed up to 15 years. Outside, they are covered with a shell, inside of which there are up to 300 lobules. They house the seminal canals and connective tissue. Through the vas deferens, the germ cells enter the ejaculatory ducts, which open into the urethra. The sperm itself consists of a head, neck, tail. These cells begin to be produced during puberty. The process continues until old age. Their number in sperm, which is discarded at a time, can reach 200 million. Male sex glands produce the following hormones: androgens (testosterone), a small amount of estrogen.

Testosterone as a hormone of masculinity

This hormone is synthesized from cholesterol by special Leydig cells. Its main function is to maintain sexual desire, to ensure normal potency.

Its influence on the formation of skeletal musculature, bone growth has been established. Testosterone is directly involved in body hair growth (according to the male principle), because of its action, the vocal cords become thickened (as a result, the voice becomes coarser). Well, and, of course, the growth of the testicles, penis and prostate gland also depend on its production. Any decrease in the amount of this hormone can result in infertility. If there is a deficiency during puberty, then the development of the genitals slows down in young men, the muscles weaken, and there is little body hair. Lack of testosterone after this period can lead to impotence. Poor testicular function also significantly affects a man's weight. Moreover, you can observe both its growth and decrease in body weight. Testosterone naturally decreases after age 60.