Effects of steroid hormones and growth factors on the development of the male mouse reproductive tract in vitro

In order to determine what growth-promoting factors may be involved in androgen-induced male reproductive tract development, the newborn mouse urogenital sinus region with seminal vesicles attached was cultured for 5 days on collagen gel matrix in a serum-free medium composed of DMEM and Ham's F-12 (1:1) supplemented with BSA, insulin, cholera toxin and transferrin. Testosterone and 5 alpha-dihydrotestosterone (DHT) stimulated development of seminal vesicle (SV), coagulating gland (CG), prostate (P) and bulbourethral gland (BG). Epidermal growth factor (EGF) stimulated development of CG, P and BG, but inhibited that of SV. Transforming growth factor-alpha (TGF-alpha) inhibited SV development, but had stimulatory effects on both CG and P. Addition of anti-EGF antibody significantly inhibited the DHT-induced development of CG and BG, but not of SV and P. These findings suggest that both EGF and TGF-alpha have organ-specific regulatory actions on male reproductive tract development and that EGF may mediate the action of DHT in the development of CG and BG.