Inter-individual differences of (+)-4-[4-(4-methylphenyl)phenylmethoxy-1-piperidinyl]butyric acid ((+)-MPPB) disposition in rats.

Inter-individual differences of drug plasma concentration were recognized in male Sprague-Dawley (SD) rats after a p.o. or i.v. administration of (+)-MPPB. Rats could be divided into two phenotypes, the rapid-metabolizing group (RM) and the slow-metabolizing group (SM). The hepatic clearance (CLliver) of RM was about 10 times larger than that of SM. Outbred SD(male, female), and Wistar(male) rats were mixtures of RM and SM. On the other hand, all inbred Lewis(male) rats were RM, and all inbred F344(male) and ACl(male) rats were SM.