ASSESSMENT OF PROSTATIC PROTEIN SECRETION IN TISSUE RECOMBINANTS MADEOF UROGENITAL SINUS MESENCHYME AND UROTHELIUM FROM NORMAL OR ANDROGEN-INSENSITIVE MICE

Urogenital sinus mesenchyme (UGM) from normal, androgen receptor-posit ive mice appears to instructively induce prostatic morphology in urina ry tract epithelium from both normal and androgen-insensitive (Tfm) mi ce. This indicates that epithelial androgen receptors are not necessar y for prostatic development. However, the secretory function of these tissue recombinants has never been assessed. In this study antisera to androgen-dependent dorsolateral prostate (DLP) secretion were used in immunocytochemistry, Western blotting, and immunoprecipitation techni ques to detect the presence of these prostatic proteins in tissue reco mbinants made with either normal or Tfm epithelium. In a majority of c ases, UGM plus normal bladder or urethral epithelium developed into pr ostatic tissue that produced androgen-dependent DLP proteins. Hence UG M appeared to be capable of instructively inducing a functional prosta tic phenotype in these normal heterotypic epithelia. With rare excepti ons, tissue recombinants of UGM plus Tfm bladder or urethral epitheliu m did not produce full prostatic cytodifferentiation or mouse DLP prot eins, indicating that epithelial androgen receptors are important for the final stages of morphogenesis and in the initiation of secretory f unction in the prostate.