Effects of Sino-Japanese herbs in the family Labiatae on the hepatic drug metabolizing enzymes and lipid peroxidation in rats

The effects of hot water extracts (HWEs) and distanninized fractions (DTFs) from 9 kinds of Labiatae herbs on rat hepatic lipid peroxidation (LPO) and the activities of aminopyrine N-demethylase (APD) and aniline hydroxylase (ANH) were examined in vitro. The APD activity was inhibited by the HWEs from 6 herbs, of which the effect of HWE from Ogon was remarkable. The APD activity was increased by HWE from Shisoshi. The inhibitory effect of the HWE from Ogon was not different compared that of the DTF from Ogon, whereas the APD activity was decreased in the DTF from Shisoshi in comparison with that of the HWE. The ANH activity was inhibited by the HWEs from 7 herbs. Except in the case of Kakho and Shisoyo, the inhibitory effects of the HWEs were enhanced by these of the DTFs from the 7 herbs, of which the effect of DTF from Ogon was remarkable. LPO was inhibited by the HWEs from 8 herbs. Especially, HWE from Ogon strikingly inhibited LPO, and this effect was retained by the DTF from Ogon. The present results suggested that Ogon, which showed remarkable effects on LPO, and the activities of APD and ANH might also exert their effects in vivo.