EFFECT OF ETHANOL ADMINISTRATION TOGETHER WITH HIGH-PROTEIN OR LOW-PROTEIN DIET ON LIPID-COMPOSITION OF INTESTINAL MICROVILLUS MEMBRANE IN RATS

Ethanol feeding daily for 40 days to rats enhanced cholesterol, triglycerides, phospholipids (PL), and glycolipids contents of intestinal brush borders. The observed increase in membrane PL was reflected in phosphatidyl serine, phosphatidyl inositol, phosphatidyl choline, and phosphatidyl ethanolamine. Feeding of an 8% protein (low protein; LP) diet to rats reduced the cholesterol content but augmented PL, triglyceride, and cerebroside contents of brush borders compared with the control values. Membranes from ethanol-fed, malnourished animals revealed a decrease in membrane PL and triglyceride contents compared with those values for LP-fed rats. Feeding of a 30% protein (high protein; HP) diet to rats significantly increased various lipid fractions ( cholesterol, PL, cerebrosides, and gangliosides) of intestinal microvillus membrane (MVM) compared with those of the controls. Ethanol administration together with the HP diet reduced membrane cholesterol, PL, triglycerides and glycolipids contents compared with those values for HP-fed animals. Thus, the feeding of a HP diet prevented the lipid accumulation in the rat intestine induced by chronic ethanol feeding. These results suggest that lipid composition of intestinal MVM is modified by ethanol and dietary protein regimens. The sensitivity of MVM lipid composition to ethanol is influenced by the dietary protein content of the animals.