The Hormonal Maintenance and Restoration of Guinea Pig Seminal Vesicle Fibromuscular Stroma

Abstract
Using the separated epithelium and muscle preparation of the guinea pig seminal vesicle, studies to investigate the hormonal control of epithelial collagen, muscle collagen and muscle cells were designed. All hormone treatment regimens involved a comparison of the effects of hormone maintenance (hormone treatments initiated on the day of castration) vs. hormone restoration (hormone treatments initiated after a castration-induced regression) on these 3 components of the fibromuscular stroma. In the epithelium, castration induced a 35% decline in collagen content, which was either returned to normal by androgen restoration or prevented by androgen maintenance. In all androgen treatment regimens, changes in epithelial collagen correlated with changes in epithelial wet weight, cell number, RNA content and cell size. In contrast, growth of the epithelium was not stimulated by estrogen maintenance or restoration. Castration reduced muscle wet and dry weight, as well as cell size and RNA content, but there was no effect on cell number and collagen content. Androgen maintenance or restoration reversed the castration-induced regression in all parameters and also caused collagen content to increase 35% above normal. Estrogen maintenance of castrates sustained wet weight, dry weight and RNA content at normal and stimulated supranormal increases in both collagen content and cell number. Similarly, estrogen restoration induced supranormal increases in collagen content and returned RNA content to normal. Estrogen''s ability to stimulate supranormal increases in cell number and restore wet and dry weight to normal was lost after a castration-induced muscle regression. Components of the guinea pig seminal vesicle fibromuscular stroma were sensitive to androgens and/or estrogens. The action of androgen on these tissue components was independent of the state of tissue regression, while with the exception of RNA and collagen content, all the effects of estrogen were significantly reduced with castration-induced regression of the tissue.