EFFECTS OF CAFFEINE AND SAPONIN ON ALCOHOL ABSORPTION AND METABOLISM|
Hirose M., Tsukamoto S., Kanegae T., Isobe E., Nagoya T.*, Hojo K.**
Department of Legal Medicine, * Department of Common-Use Facilities for Medical Research and ** Third Department of Internal Medicine, Nihon University School of Medicine, 30-1 Ohyaguchi-Kamimachi, Itabashi-Ku, Tokyo 173, Japan
The effects of the seed saponin of Thea sinensis L. (ryokucha saponin) and caffeine on ethanol absorption and metabolism in mice were investigated. Saponin and caffeine were orally given to the mice 1 hour before administration of ethanol (2 g/kg). Blood, liver and stomach were obtained 0, 1, 3 hours after ethanol administration. The ethanol, acetaldehyde and acetate concentrations in each specimen were measured by head space gas chromatography. The motility of the intestine was tested on the small intestine of the mice by Magnus instrument. Both saponin and caffeine decreased the ethanol levels in the blood and liver but increased that in the stomach 3- or 4-fold over the control level. This result suggests that saponin and caffeine inhibit alcohol absorption. Strips of the intestine were attached with a string to the end of a rod which was mounted in a bath (Magnus instrument). The opposite end of the tissue was secured to a strain gauge and tension measurement were recorded. We proved that the motility of the small intestine was inhibited by saponin orcaffeine with applying Magnus instrument on the digestive system of the mice in vitro. Based on these results, we speculate that caffeine and the seed saponin suppress alcohol absorption by slowing gastric emptying and inhibiting absorption across the membrane of the digestive tract.