Growth responses of the guinea pig seminal vesicle epithelium and muscle to long-term treatment with dihydrotestosterone and/or estradiol benzoate.

The three-month treatment regimen with dihydrotestosterone (DHT) and estradiol (E2B) which was capable of producing a supranormal growth of the canine prostate gland equal to that occurring in spontaneous canine benign prostatic hypertrophy, failed to produce similar changes in either the epithelium or smooth muscle of the guinea pig seminal vesicle. The factor limiting the growth response in the seminal vesicle epithelium and muscle of the castrate guinea pig proved to be the lack of a DHT-estradiol benzoate (E2B) synergism, since the growth responses in seminal vesicle tissues to the three-month treatment with DHT alone were similar to that previously recorded for the canine prostate. The lack of a DHT-E2B synergism in the guinea pig seminal vesicle may be responsible for the absence of spontaneous hypertrophy of this organ and other organs such as the human seminal vesicle with advancing age.