Androgens are Necessary for the Establishment of Secretory Protein Expression in the Guinea Pig Seminal Vesicle Epithelium1

The guinea pig seminal vesicle epithelium (GPSVE) synthesizes and secretes milligram quantities of four related secretory proteins in an androgen-dependent manner. To investigate the role of androgens in the establishment of secretory protein synthesis during the development of the GPSVE, animals were castrated at Day 5, approximately 10 days before secretory protein accumulation begins in intact animals. Castration did not eliminate secretory protein mRNA from the SVE, but it did indefinitely postpone the developmentally programmed increase in secretory protein mRNA. Injection of neonatally castrated guinea pigs with either estradiol or dexamethasone did not alter levels of secretory protein mRNAs. However, treatment of castrated neonates with either testosterone propionate or dihydrotestosterone (DHT) led to specific increases in secretory protein mRNAs within 4 days. Although neonatally castrated animals accumulated and translated significant amounts of secretory protein mRNA, the newly synthesized secretory proteins failed to accumulate until exogenous androgens were provided. This observation suggests that androgens regulate both the accumulation of secretory protein mRNA and the accumulation of secretory proteins in the GPSVE.