[The characteristics of hormone responsiveness of glandular epithelium and stroma in male accessory sex organs]

We investigated the hormonal responsiveness of gland and stroma in the male accessory sex organs (ventral prostate, dorsolateral prostate and seminal vesicle). Immature rats (3 weeks old) were castrated and left untreated for 4 weeks and then distributed at random into 3 groups, A, B, C. The rats in groups A, B and C were injected subcutaneously with 0.2 ml of soybean oil, 5 alpha-dihydrotestosterone (DHT, 500 micrograms/day) or estradiol-17 beta (E2-17 beta, 5 micrograms/day), respectively, for 14 days before they were killed. DHT administration in prepuberal castrates stimulated collagen synthesis and accumulation in the stroma of male accessory sex organs as well as the proliferation and differentiation of the glandular epithelium in these organs. In E2-17 beta treated rats, the glandular epithelium of ventral prostate and seminal vesicle had mostly a single layer structure, but the glandular epithelium of dorsolateral prostate had a mostly multilayer structure. On the other hand, in E2-17 beta treated rats, the EMBP content, an indicator of glandular epithelium differentiation in male accessory sex organs, did not increase even in the dorsolateral prostate which showed a multilayer gland epithelium. Collagen synthesis and accumulation in the seminal vesicle was stimulated by E2-17 beta treatment several times as much as in the ventral and dorsolateral prostate. Histological investigation demonstrated that the seminal vesicle in prepuberal castrates treated with E2-17 beta resembled that of fibromuscular type human benign prostatic hyperplasia.