Anti-androgen TSAA-291. I. Anti-androgenic effects of a new steroid TSAA-291 (16 beta-ethyl-17 beta-hydroxy-4-oestren-3-one) and its derivatives.

Anti-androgenic properties of newly synthesized steroidal compounds, TSAA-291 and its derivatives, were studied in the rat. (1) Subcutaneous administrations of TSAA-291 and TSAA-272 were effective in depressing the weight of seminal vesicles and ventral and dorsal prostates in the adult rat. (2) TSAA-291, TSAA-328 and TSAA-272 were shown to be anti-androgenic by the subcutaneous or oral route in the immature castrated male rat treated with testosterone propionate. The dose-response curves of all the test agents expressed in terms of percentage inhibition were approximately parallel to each other. Cyproterone acetate depressed the weight of levator ani muscle dose-dependently, whereas TSAA-291, TSAA-328 and TSAA-330 did not inhibit the muscle weight in a dose range sufficiently effective in inhibiting the weight of seminal vesicles and ventral and dorsal prostates. (3) TSAA-291 was also anti-androgenic against androstenedione and dehydroepiandrosterone. (4) Local administration of the anti-androgenic compounds into the left seminal vesicle or left testis of the young adult rat depressed the weight of the seminal vesicle or testis on the treated side as compared with the vehicle-injected contra-lateral side.