Effect of Chronic Ethanol Feeding upon the Catabolism of Protein and Lipid Moieties of Chylomicrons and Very Low Density Lipoproteins in Vivo and in the Perfused Heart System

Abstract

Effect of chronic ethanol feeding for 6 weeks to male Wistar rats upon the catabolism of rat chylomicrons and very low density lipoproteins was investigated both in vivo and in the perfused heart system. The exponential decay curves in the plasma compartment or in the perfused heart system of these lipoproteins labeled in the protein or triacylglycerol or cholesterol moieties were determined. It was found that chronic ethanol feeding inhibited the catabolism of both protein and triacylglycerol moieties by 26-35%, whereas that of the cholesterol moiety was inhibited by 67-71%. Since the catabolism of the triacylglycerol moiety takes place essentially in the extrahepatic tissues while that of the cholesterol moiety occurs in the liver, it is concluded that ethanol affects the catabolism of triacylglycerol-rich lipoproteins in the liver more than in the extrahepatic tissues.