Comparison of Reproductive Tissue Weights in the Enhanced Hershberger Assay of 17.ALPHA.-Methyltestosterone between Peripubertal and Castrated Rats.

Abstract

We studied the comparative changes in weight of the accessory sex organs in intact and castrated rats to which 17α-methyltestosterone (MT) had been administered. In study 1, MT was administered to SD rats at doses of 0.1, 1, and 10 mg/kg/day. In castrated rats that received oral administration, the ventral prostate was heavier in those given 1-10 mg/kg, while in intact rats the increase of this organ was not observed. In castrated rats that received subcutaneous injections, the bulbo cavernous/levator ani muscle (BC/LA) was heavier in intact rats given 1-10 mg/kg, while in castrated rats, BC/LA was heavier at all doses of MT. In study 2, MT was administered subcutaneously to SD rats at doses of 0.001, 0.01, and 0.1 mg/kg/day. The ventral prostate, seminal vesicle, and BC/LA were heavier in castrated rats given 0.1 mg/kg, while the only increase in intact rats was in the BC/LA of those given 0.1 mg/kg. In study 3, MT was administered orally to AP rats at doses of 25 and 100 mg/kg/day. The prostate and BC/LA were heavier in intact rats given 25 and 100 mg/kg, and in those intact rats given 100 mg/kg, the Cowper’s glands and seminal vesicle were heavier. In castrated rats, all organs were heavier in 25 and 100 mg/kg groups. This study demonstrates that treatment of intact and castrated rats induces changes in the weights of the accessory sex organs, and that castrated rats are more sensitive to MT than are intact rats.