An early example of research in androgen deficiency
In a healthy man, approximately 95% of the androgens present are accounted for by testosterone produced in the testes (Figure 14.1). Luteinizing hormone (LH) is secreted by the pituitary gland, which regulates the conversion of cholesterol to testosterone in the Leydig cells. Testosterone, in turn, is metabolized to dihydrotestosterone (DHT) by 5α-reductase and undergoes aromatization to estradiol by aromatase. Dihydrotestosterone has been linked to prostate hypertrophy and male alopecia.7 The balance of the androgen is mainly in the form of DHEA produced by the adrenal glands.