CHARACTERIZATION OF THE SPECIFIC ANDROGEN RECEPTORS IN THE HUMAN PROSTATE GLAND

A search has been conducted for specific androgen-binding proteins in soluble extracts of normal human prostate tissue and in surgical samples removed at retropubic prostatectomy for benign prostatic hyperplasia. Proteins with a particularly high affinity for a metabolite of testosterone, 5\g=a\-dihydrotestosterone,have been identified in studies on the binding of 3H-labelled steroids in vitro. The 5\g=a\-dihydrotestosterone-protein complexes have been partially characterized using sucrose density gradient centrifuga-tion and gel-exclusion chromatography. The androgen receptors in the human prostate gland are remarkably similar to those previously described in the accessory sexual glands of experimental animals. These findings have been confirmed by the analysis of extracts of hyperplastic prostate glands labelled by the administration of [3H]testosterone in vivo. No attempt was made to correlate the degree of binding with the histological appearance of the specimens ofhyperplastic prostate or to determine whether the receptors were principally present in the hyperplastic nodules. Such androgen\x=req-\ binding proteins were not present in serum, skeletal muscle or adipose tissue. The possible relevance of these findings to the onset of clinical disorders in the human prostate gland is briefly discussed