Time-dependent induction of hepatic cytochrome p450 enzyme activity and mrna expression by bilobalide in rats

Abstract

A single dose by gavage of bilobalide (30 mg/kg) was found to produce a time- dependent induction of hepatic cytochrome P450 (CYP) enzyme activity and protein expression in rats. An RT-PCR study further showed that mRNA expression of CYP2B was maximal at 6 h. Plasma and liver bilobalide concentration in rats following administration of Ginkgo biloba extract equivalent to bilobalide of approximately 40 mg/kg showed a similar response to that exhibited by mRNA expression. These findings suggest that bilobalide markedly induced hepatic CYPs, but the induction could be mitigated due to rapid elimination from the liver. © 2009 The Japanese Pharmacological Society.