Induction of cytochrome P-450 related metabolic activities in the rat ventral prostate

Rats were treated with β-naphthoflavone (BNF) or phenobarbital (PB), 80 mg kg i.p. for 4 days and microsomes prepared from the ventral prostate were assayed for aryl hydrocarbon hydroxylase (AHH), 7-ethoxyresorufin-O-deethylase (7-EOD) and NADPH-cytochrome c reductase activities. The relative increase after BNF treatment was approx. 1000 times for AHH, and 800 times for 7-EOD, while the NADPH-cytochrome c reductase activity was not significantly altered. PB treatment caused no significant effects. Treatment with BNF led to an increased in vitro formation of all measured benzo(a)pyrene (B(a)P) metabolites, especially phenols. Carbon monoxide (CO) and α-naphthoflavone (α-NF) inhibited 7-EOD- and AHH-activities. The rat ventral prostate contains inducible cytochrome P-450-dependent enzymes, a circumstance of potential importance in the etiology of prostatic carcinoma.