Testosterone

Testosterone is the primary male sex hormone and anabolic steroid in males.^[1] In humans, testosterone plays a key role in the development of male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristics such as increased muscle and bone mass, and the growth of body hair. It is associated with increased sex drive, the inclination to impress partners and other courting behaviors.^[2] See also Testosterone.

Testosterone is a steroid from the androstane class. It exerts its action through binding to and activation of the androgen receptor. Ligand binding domain (LBD) containing an active site which binds intramolecularly the N-terminal FXXFL motif or coactivators with the same motif.^[3] Water molecules are shown as red spheres. Human androgen receptor bound to testosterone (2ylo).