Testosterone, the male hormone, is the most important androgen in the body. In men, Leydigin cells produce most of the testosterone in the testicles. Testosterone is also produced in the adrenal cortex and on the periphery in converting the androstenedione. Women have much lower testosterone levels than men. However, it also has a significant effect on the female body. In women, testosterone is produced in the ovaries and in the adrenal cortex. Hormonal regulation of testosterone is maintained and controlled by the hypothalamo-pituitary-gonad axis.


Androgens have androgenic, anabolic and psychological effects on the body. Androgenic effects include penis and prostate growth, hair growth in various areas, and baldness. The anabolic effects include larynx enlargement, vocal cords enlargement, lipid changes, muscle growth, fat loss, sebaceous gland enlargement and blood cell formation. The psychological effects of androgens include changes in libido, drive, sexual behavior and aggression.

Anabolic steroids are derived from the synthetic derivatives of testosterone. In medicine, anabolic steroids are used for testing to obtain the anabolic effects of testosterone without the secondary virilizing effects of androgens so that children and women can also use them. However, the attempt failed. For this reason, the term “anabolic steroid” is misleading. It is more correct to use the term “anabolic androgenic steroids”.

Testosterone is a naturally occurring androgenic anabolic steroid in the body. Testosterone and other anabolic steroids on the same chemical structure. Attempts have been made to modify the structure of synthetic anabolic steroids by increasing the anabolic effect and reducing the androgenic effect. The ratio of anabolic and androgenic activity of testosterone is 1:1, and it has a strong influence.

In other anabolic steroids, this relationship varies with the predominance of the anabolic effect. In addition, the structure of anabolic steroids has been modified in order to adjust the administration rate, the absorption, the duration of exposure and the aromatization of the substance. Consequently, anabolic steroids differ in relation to anabolic and androgen, in terms of administration (oral, intramuscular, dermal), in terms of absorption, in duration of action in the body and in aromatization in estrogen.

The history of the use of testosterone dates back to 1935, when testosterone is isolated after successes of the bull testicles. It has been fairly quickly discovered that oral testosterone is hepatotoxic and a half-frequent. After the synthesis of testosterone, the injectable propionate is available on the market and later, since the year 1950, the enanthate has prolonged action. In the 1950s and 1960s the pharmaceutical industry became increasingly interested in new androgens, and by the end of the 1980s a great name of anabolic steroids had been developed, over a thousand.

Influencing mechanism

Testosterone and all anabolic steroids act through androgen receptors. Androgen receptors are located on the X chromosome of cells and are found throughout the body. In addition to muscles, androgen receptors affect the heart, the immune system and the nerve system.


The popularity of testosterone as dopant is due to its strong effect on the force and the muscle mass. Testosterone also affects lipolysis, which is the degradation of fatty cells. Short and long term use of anabolic steroids results in increased cellular growth due to increased protein synthesis. The growth of muscle cells induced by testosterone is due to the activation of satellite cells and the growth of muscle cell nuclei.

The number of androgen receptors is limited, and usually normal testosterone levels are enough for them. Therefore, muscle growth is not necessarily due to an excess of anabolic steroids. Another mechanism that explains muscle growth may be the effect of anabolic steroids on cortisol. Cortisol is a catabolic hormone and anabolic steroids can reduce its effect. The inhibitory effect of anabolic steroids on the myostatin gene is also thought to be a mechanism for muscle growth. Myostatin regulates muscle growth. Testosterone also increases the secretion of growth hormone and insulin-like growth factor.