Induction of liver cytochrome P450 2B1 by beta-ionone in Sprague Dawley rats.

Induction of liver cytochrome P450 2B1 by beta-ionone was investigated in male and female Sprague Dawley rats. Administration of beta-ionone subcutaneously 72 and 48 hr before sacrificing the animals not only significantly induced the liver microsomal activity of pentoxyresorufin O-dealkylase, but also clearly increased in the level of cytochrome P450 2B1 protein. The induction of cytochrome P450 2B1 by beta-ionone was much greater in male rats than in female rats. A slot blot analysis showed that the mRNA level was increased from 6 hr after treatment with beta-ionone in male rats and from 12 hr after treatment in female rats. Taken together, the present results indicate for the first time that the induction of cytochrome P450 2B1 by beta-ionone might be regulated by the accumulation of mRNAs.