[Sex hormones in the male].

The measurement of androgen hormones in reduced times using small samples of blood is nowadays possible by using the radioimmunological techniques. The level of testosterone in plasma is directly correlated with glandular secretion, though several different factors may provoke variations of such level. The measurement of testosterone in plasma is used for evaluation of testicular function. The main applications of testosterone determination in clinical practice are reported; special stress is laid on diagnosis on male hypogonadisms and on the study of testicular function in male sexual impotence.