Comparison of the Metabolites Formed in Rat Prostate Following thein VivoAdministration of Seven Natural Androgens*

The incorporation of radioactivity by rat prostate has been measured following administration of seven tritium-labeled natural androgens to separate groups of castrated functionally hepatectomized rats. In addition a study has been made of the identity and subcellular localization of metabolites formed from each steroid. With every androgen tested radioactivity was detected in cytoplasmic and nuclear fractions at intervals ranging from 5 min to 1 hour after the administration of the hormone. Highest levels of nuclear radioactivity were achieved with testosterone, dihydrotestosterone and androstanediol; intermediate levels with androstanedione, androstanedione, and androsterone; a low level with dehydroepiandrosterone. Every androgen gave rise to several metabolites in prostatic cytoplasm and invariably one of these was dihydrotestosterone. In nuclei dihydrotestosterone consistently was found to be the major metabolite. There was a striking absence of any other significant nuclear product except for testosterone in three instances A and androstanediol in one. (Endocrinology 89: 1212, 1971)