Androgen metabolism and actions in rat ventral prostate epithelial and stromal cell cultures
The rat ventral prostate requires androgens for normal development, growth, and function. To investigate the relationship between androgen metabolism and its effects in the prostate and to examine differences between the epithelial and stromal cells, we have established a system of primary cell cultures of immature rat ventral prostate cells. Cultures of both cell types after reaching confluency (6–7 days) actively metabolized 3H-labelled testosterone (T), 5α-dihydrotestosterone (5α-DHT), 5α-androstane-3α,17β-diol, and 5α-androstane-3β,17β-diol. The epithelial cells actively reduced T to 5α-DHT and formed significant amounts of 5α-androstane-3,17-dione from T, 5α-DHT, and 5α-androstane-3α,17β-diol. All substrates were converted to significant amounts of C19O3metabolites. The stromal cells also metabolized all substrates, but very little 5α-androstane-3,17-dione was formed. The metabolism studies indicate that both cell types have Δ4-5α-reductase, 3α- and 3β-hydroxysteroid oxidoreductase and hydroxylase activities. The epithelial cells have significant 17β-hydroxysteroid oxidoreductase activity. The epithelial cells cultures grown in the presence of T have higher acid phosphatase (AP) contents (demonstrated histochemically and by biochemical assay). Tartrate inhibition studies indicate that the epithelial cells grown in the presence of T are making secretory AP. Stromal cell AP is not influenced by T. The results indicate that the cultured cells maintain differentiated prostatic functions: ability to metabolize androgens and, in the case of the epithelial cells, synthesize secretory AP.