抄録
Some Japanese herbal medicines (Kampo medicines) have been shown to inhibit the activity of aminopyrine N-demethylase in rat liver microsomes. Namely, Sho-seiryu-to and Keishi-kajutubu-to inhibited not only aminopyrine N-demethylation but also erythromycin N-demethylation, 7-ethoxycoumarin 0-deethylation, 4-nitrophenol 7-hydroxylation, desipramine 2-hydroxylation and coumarin 7-hydroxylation in rat liver microsomes to varying extents. Cinnamon Bark, Schisandra Fruit and Ephedra Herb, which are crude medicine ingredients contained in Sho-seiryu-to, showed a higher potential to inhibit erythromycin N-demethylation than Sho-seiryuto and other components such as Pinellia Tuber, Glycyrrhiza, Asiasarum Root and Peony Root at the same concentrations.
From these results, some Kampo medicines are thought to have an inhibitory effect on cytochrome P450 in rat liver microsomes, and that the inhibitory effect of Sho-seiryu-to on erythromycin N-demethylation may be, at least in part, associated with the ingredient (s) of Cinnamon Bark, Schisandra Fruit and/or Ephedra Herb.
