[Plasma cholesterol distribution in the intestinal villus of the rat]

1. The distribution of plasma cholesterol in the various tissues of the rat intestine and in the epithelial cells localized at the different levels of the villus was investigated. Isotropic equilibrium and isotopic infusion or pulse were performed and analyzed by biochemical and radioautographical techniques. 2. The plasma cholesterol exchanges 55% of the total cholesterol in the epithelium and more (80%) in the core of the villus. The flow of plasma cholesterol through the epithelial basal membrane is lower than through the capillary membrane, but, it does not depend on the localization of the epithelial cell in the intestine (jejunum or ileum) or on the villus (crypt or top). 3. These results suggest the existence of fast intercellular cholesterol exchanges through the lateral membranes and heterogeneity of synthetic and plasma cholesterol within the epithelial cell.