Hormonal control of accessory sex organ fibromuscular stroma.

Using the surgically separated epithelium and muscle preparation of the guinea pig seminal vesicle, quantitative determinations were made of the hormonal sensitivities of three components of male accessory sex organ fibromuscular stroma. The parameters measured were epithelial collagen, muscle tissue cell number, and muscle tissue collagen. Epithelial collagen increased approximately tenfold between one week of age and adulthood. This growth was completely prevented by castration and was sustained at normal levels of maintenance of prepubertal castrates with dihydrotestosterone (DHT). Castration of adult animals reduced epithelial collagen 40%; such reductions were prevented by DHT treatment. Estrogen treatment of adult castrates, either alone or in combination with DHT, had no anabolic effect on the epithelium. In all of these studies, changes in epithelial collagen correlated with changes in epithelial wet weight, DNA content, and RNA/DNA. From 1 week of age to adulthood, growth of seminal vesicle muscle involved marked increases in wet weight, DNA content, RNA/DNA, and collagen content. Increments in all parameters were prevented by prepubertal castration and were sustained at normal levels in castrates by DHT treatment. However, in adult animals, muscle DNA content and collagen levels were insensitive to castration and androgen replacement; only tissue weight and cell size (RNA/DNA) were androgen sensitive. Estrogen treatment of adult castrates caused supranormal increases in muscle DNA and collagen; changes in collagen were irreversible. The effects of simultaneous treatment of DHT and estrogen did not differ from those of DHT alone. Therefore, normal postnatal development of the stromal components, epithelial collagen, muscle cells, and muscle collagen was androgen dependent, but in adult animals, only epithelial collagen retained androgenic sensitivity. Estrogen induced supranormal and irreversible growths in the muscle.