Males synthesize androgens at a much higher level than females because they have testicles- Testicles are referred to as "testes" and are located in the scrotum. (Hey, I once received a letter asking how to get "testes" and where do they come from. So stop with the "hey stupid" comments) They also produce androgens through biosynthesis due to enzymatic pathways stalling from the adrenal glands which are located near the kidneys. Predominantly, the adrenal glands (there are two) produce epinephrine, which is also called adrenaline, but also produce other hormones commonly referred to as prohormones through a biosynthesis processes and due to conversion enzymes. The lion's share of a male's androgens are produced by the Leydig's cells located in the testes. The most active and dominant androgen is testosterone, which is of course the main focus of this discussion.

Testosterone production is governed by the hypothalamus- pituitary -testes -axis referred to hereafter as the "HPTA". The HPTA has a series of checks and balances all influenced by serum (the fluid part of the blood containing the active hormones which circulate through the body) levels of several hormones and pro-hormones. If testosterone production is too low. the testes signal the hypothalamus to release more leutenizing-hormone-releasing- homione (LHRH). The circulating LHRH tells the pituitary to release more leutenizing- hormone (LH) and follicle-stimulating-hormone (FSH). When the circulating FSH and LH reach the testes, they signal the Leydig's cells to produce more sperm and testosterone.

When testosterone levels are too high the testes signal the hypothalamus to release less LHRH...and then "the boy's" production process decreases or stops. It is quite interesting that elevated estrogen levels can signal a production decrease for androgens, such as testosterone, far more significantly than any androgen. Please, read that again to be sure you understand the basic HPTA function. It does relate heavily to the effects and effectiveness of exogenous (occurring outside the body) AAS use by athletes.