Effects of androgen and estradiol administration on the weight of the ventral prostate, seminal vesicles, and testes of immature rats.

This study was designed to investigate the effects of pharmacologic doses of estradiol on th biologic actions of testosterone and 5alpha-dihydrotestosterone when administered to immature (21 to 28 of age) male rats. The weights of the prostate, seminal vesicles, and testes were used as the indicators of androgen effects. Estradiol had no effects on the testosterone- or 5alpha-dihydrotestosterone-induced increases in prostate weight over the 12 days after the androgen injection. Estradiol acted synergistically with testosterone but not 5alpha-dihydrotestosterone on the increases in seminal vesicle weight. Estradiol had no effect, by itself, on the rate of testes growth. Both androgens resulted in a decreased rate of testicular growth and this was not infuenced by estradiol.