EFFECT OF RETINOIC ACID ON PROSTATIC DEVELOPMENT

BACKGROUND AND METHODS. To assess the effect of retinoids on prostatic ductal branching morphogenesis, anterior prostates from newborn rats were cultured under serum-free conditions for 6 days in the presence o f testosterone (10(-8) mM) plus 13-cis-retinoic acid (13-cis-RA), all- trans-retinoic acid (at-RA), or N-4-hydroxyphenyl-retinamide (4-HPR). Measures of morphologic complexity were computed and compared between specimens of different treatment groups. RESULTS. Prostatic ductal gro wth and branching were inhibited in a dose-dependent fashion by both 1 3-cis-RA and at-RA, but not by 4-HPR. This inhibitory effect of 13-cis -RA was reversible, as the prostatic ducts resumed branching and growt h after removal of retinoic acid from the culture medium. Using revers e transcription polymerase chain reaction, we then investigated the ex pression of nuclear receptor genes for retinoic acid. CONCLUSIONS. Thi s showed the presence of RAR-beta and RAR-gamma in the 0-day prostate, suggesting that the effects of these retinoids on ductal morphogenesi s may be via these receptors. (C) 1997 Wiley-Liss, Inc.