The Effects of Various Androgens on Peripheral Structures in the Castrated Male Rat

Summary. A study was made of the relative abilities of propionates of eight naturally occurring androgens to maintain sexual accessory organ weights and numbers of penile spines in castrated adult male rats. Experiments involved daily treatment with either 150 μg/day for 5 weeks starting on the day of castration or 300 μg/day for 10 days starting 2 weeks after castration. The compounds tested were (a) testosterone, (b) dihydrotestosterone, (c) androstenedione, (d) androstanedione, (e) 3α-androstanediol, (f) androsterone, (g) 3β-androstanediol, and (h) androstenediol and they fell into three activity groups: (1) highly effective (a, b) as judged by all peripheral measures, (2) considerably less potent (c, d, e, f) than Group 1, with a negligible effect on the seminal vesicles, and (3) no effect detected (g, h). In general, the response of the penile spines followed that of the prostate and was equally sensitive. The conclusions from these results were basically in agreement with studies using immature male rats.