The Effect of Bile Acids on Cholesterol Absorption, Deposition and Synthesis in the Rat1

Summary. The effect of cholic, desoxycholic and dehydrocholic acid on the intestinal cholesterol absorption and on the simultaneous deposition of cholesterol in the liver has been studied in balance experiments on rats. Bile acid ingestion on a fat‐free diet did not increase the absorption of cholesterol. When the effect of the bile acids were tested on a diet containing 5 per cent arachis oil or 9 per cent oleic acid, a stimulating effect on cholesterol absorption was only observed in one group fed cholic acid with arachis oil. The variability in these experiments was considerable and no clearcut conclusion could be drawn concerning the effect of bile acids on the intestinal absorption of cholesterol in the presence of dietary fat or fatty acids. The deposition of cholesterol in the liver was markedly increased by cholic or desoxycholic acid ingestion and moderately but definitely increased by dehydrocholic acid ingestion. The serum cholesterol levels of the rats fed bile acids reflected in most cases the increased deposition in the liver. The simultaneous measurements of cholesterol absorption and deposition indicated a post‐absorptive effect of dietary bile acids on cholesterol metabolism. Cholic acid feeding, in the presence or absence of dietary cholesterol did not increase the hepatic cholesterol synthesis in vitro, as judged by the incorporation of 1–C14 acetate into cholesterol in surviving liver slices. The inference has been made that bile acid ingestion probably interferes with the catabolism of cholesterol in the liver.