Effects of menthofuran, a monoterpene furan on rat liver microsomal enzymes, in vivo

Abstract

Oral administration (250 mg/kg) of menthofuran, a monoterpene furan, to rats once daily for 3 days caused hepatotoxicity as judged by a significant increase in serum glutamate pyruvate transaminase (SGPT) and decreases in glucose-6-phosphate and aminopyrine N-demethylase activities. Administration of menthofuran also resulted in a decrease in the levels of liver microsomal cytochrome P-450, whereas cytochrome b 5 and NAD(P)H-cytochrome c reductase activities were not affected. These effects of methofuran were both dose- and time-dependent. retreatment of rats with phenobarbital (PB) prior to menthofuran treatment potentiated hepatotoxicity suggesting that a PB-induced cytochrome P-450 catalyzed the formation of reactive metabolite(s) responsible for the hepatotoxicity.