The principal androgen (men sex hormone) is testosterone. This steroid is manufactured
by the interstitial (Leydig) cells of the testes. Secretion of testosterone increases
sharply at puberty and is responsible for the development of the so-called secondary
sexual characteristics.
Testosterone is also essential for the production of sperm.
Production of testosterone is controlled by the release of luteinizing hormone (LH)
from the anterior lobe of the pituitary gland, which is in turn controlled by the
release of GnRH from the hypothalamus. LH is also called interstitial cell stimulating
hormone (ICSH).
The Hypothalamus produces GnRH which stimulates the Pituitary Gland which in turn
produces LH which stimulates the testes to produce testosterone
Levels of testosterone are under a negative feedback control system whereby a rising
level of testosterone suppresses the
