Testosterone in men: what is it for?
Last reviewed: 01.06.2018
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Testosterone is a male sex hormone produced in the testicles of men. If to specify, then it is developed by the so-called Leydig cells, the totality of these cells is also called the pubertal gland. In addition to testicles, testosterone is also synthesized from androstenedione, produced by the mesh cortex of the adrenal cortex. Every day the male body synthesizes about 6-7 milligrams of the hormone, the blood level in the blood ranges from 300 to 1000 nanograms per deciliter. Ironically, men do not have the exclusive right to manufacture male sex hormone - testosterone is produced in the female body (in the same adrenal cortex and in the ovaries), however, in much smaller quantities - only 1 milligram per day. Testosterone is synthesized from cholesterol, there are two variants of its synthesis, the first and second, differing not so much.
In any case, directly into testosterone, a substance called a testosterone precursor or prohormone is converted. The synthesis of testosterone occurs, as already mentioned, mainly in the testes (Leydig cells). Mainly the modes of influence of the pituitary luteinizing hormone (LH or lutropin). LH, in turn, are produced in the pituitary gland under the influence of the hypothalamic hormone, called gonadotropin-releasing hormone (GnRH, GtRH). The pituitary gland uses information about the presence of sex hormones in the blood in order to regulate the production of LH, and the hypothalamus - to regulate the production of GnRH. In any case, the increase in the level of free testosterone in the body is a signal for the hypophysis to reduce the production of LH, and once the production of luteinizing hormone falls, the production of testosterone itself also decreases.
The role of testosterone in the body of men and women
The value of the hormone testosterone for men can not be overestimated; testosterone, in fact, makes us men - it is responsible for the formation of secondary sexual characteristics. It is thanks to him that men, we are fortunate to wear lush vegetation on face and body; it is thanks to him that we have a lower voice and a more aggressive character than the fair sex. Finally, it is testosterone that can contribute to the baldness of men, not all, of course, but some. Testosterone also activates anabolic processes in the body, and this property was taken as a basis when using this hormone in medical practice and in sports.
Testosterone for women is also an important hormone. The first was a relationship between testosterone levels in women's blood and fat deposition. In the period preceding menopause, as well as after it, the testosterone level in the body of women is significantly reduced. It is during this period that women are most prone to the deposition of fats. However, testosterone was used as an aid in getting rid of surplus fat under the skin and for patients who experienced the onset of menopause only in the very distant future, but the level of this hormone in the blood was clearly below normal.
In addition, the lack of testosterone in the blood in women can significantly weaken the sex drive; a low level of testosterone contributes to the emergence of problems with concentration of attention, increases the likelihood of depressive conditions. Moreover, the lack of testosterone results in increased dryness and thinning of the skin. So, for women, the importance of this hormone is no less difficult to overestimate than for men.
The level of testosterone in the body of a man
The level of testosterone in the blood of men grows very high during the period of sexual maturation, while in the youth years testosterone can be sufficient to form an athletic build. But after 45-50 years, the level of testosterone in the male body starts steadily and quite dramatically decreases, and the estrogen level rises. Taken together, these two factors inevitably lead to various and very unpleasant disorders, among which there are problems with the prostate, cardiovascular system, memory, diseases associated with weakening immunity and even age-related gynecomastia (enlargement of the mammary glands). By the way, recent studies show that men do not have a common level of testosterone in their elderly age, but a level of free testosterone. This is due to the increase in their blood levels of globulin, which binds sex hormones. Be that as it may, during this period, additional injections of testosterone are very, very desirable. And not only injecting testosterone - to fight with an elevated level of SHBG in the blood helps insulin. The testosterone level has diurnal fluctuations: the maximum is 7-9 hours in the morning, at least 0-3 hours at night. With such fluctuations, one interesting observation is associated with an even large enough amount of a short-lived steroid (up to 100 mg of methandrostenolone) introduced into the body during the maximum period (6 am 12 noon), practically does not disrupt the production of endogenous testosterone. The statement, by the way, is not groundless - it is confirmed by practice.
In addition to diurnal fluctuations, testosterone in the blood of men also has seasonal fluctuations: it increases in spring, and its peak falls at night. Since July, testosterone levels are gradually decreasing, and the lowest level reaches by mid-September. This time is the most "favorable" for the beginning of the autumn depression.