Dose dependence of N-hydroxy-3,2'-dimethyl-4-aminobiphenyl-induced rat prostate carcinogenesis.

Groups of F344 rats were administered biweekly intraperitoneal injections of N-hydroxy-3,2'-dimethyl-4-aminobiphenyl (N-OH-DMAB) at a dose of 5, 10 or 20 mg/kg body weight or DMAB, the parent compound, at a dose of 25 mg/kg body weight, for a total of 10 times. Prostate carcinomas in the ventral lobe developed in a N-OH-DMAB dose-dependent manner (0, 17.6 and 66.7%, respectively) with limited tumor yields in other organs. Although intraperitoneal administration of DMAB was similarly found to induce prostate tumors, it also caused severe chemical peritonitis, which resulted in a high mortality. The present data confirmed that intraperitoneal administration of N-OH-DMAB provides a relatively specific induction method for models of prostate carcinogenesis.