METABOLISM AND MODE OF ACTION OF ANDROGENS IN TARGET TISSUES OF MALE RATS

Abstract

ABSTRACT The effect of testosterone and 5α-dihydrotestosterone on protein and nucleic acid content as well as on the activities of some enzymes has been studied in the ventral prostate and the seminal vesicles of immature castrated rats. Both androgens were given intraperitoneally in doses of 1 mg daily for one or three days the rats were sacrificed one day after the last injection. In the prostate it was found that 5α-dihydrotestosterone had a greater effect on DNA increase, i. e. cell proliferation than testosterone, whereas cell metabolism was stimulated by the two androgens to nearly the same extent. In the seminal vesicles a single dose led to the same results as had been obtained in the prostate, i. e. a greater cell proliferative action of 5α-dihydrotestosterone and an equal stimulation of cell metabolism by testosterone and 5α-dihydrotestosterone was also observed. When three doses of the two androgens were given, cell proliferation as well as cell metabolism in the seminal vesicles were significantly more increased after 5α-dihydrotestosterone than after testosterone. The difference of action after systemic administration of the two androgens is explained by their different accumulation and by their different peripheral metabolism in the target tissues. From the partly independent effects of various androgens on cell proliferation and cell metabolism the conclusion may be drawn that there exist at least two intracellular sites of action.