Sex-hormone-binding globulin in the plasma of normal men and patients with benign prostatic hypertrophy.

Sex-hormone-binding globulin (SHBG) was measured in the plasma of normal men aged 30--50 yr, normal men 50--70 yr of age, and men 50--70 yr of age suffering from benign prostatic hypertrophy (BPH). The level of binding proteins in normal "young" men decreased approximately 45% in normal "older" men. A 100% rise was observed in BPH patients as compared to normal older men. This increase seemed to be related to a rise in SHBG and also to the appearance of binding species of smaller molecular weight than that of SHBG.