Many chronic alcoholics suffer cardiovascular complications, including alcoholic cardiomyopathy. The relationship between ethanol consumption and cardiac function at the cellular level has not been explored in detail. Previous data have shown that lipid metabolism in myocardium is altered by chronic ethanol consumption. The main objectives for this investigation are: 1) to examine the effects of acute and chronic ethanol consumption and withdrawal on lipid composition of rat ventricular subcellular membranes (mitochondria and sarcoplasmic reticulum); 2) to examine the in vivo and in vitro effects of ethanol on phospholipid-metabolizing enzymes in subcellular fractions of rat ventricular muscle; and 3) to examine the effects of ethanol interaction with propranolol in vivo and in vitro on lipid metabolism in rat myocardial tissue. Ethanol will be administered to rats via intragastric intubation for specified time intervals after which the animals will be sacrificed at intervals after withdrawal. Blood and tissue ethanol levels will be monitored. Lipid analyses will include determination of cholesterol, cholesterylesters, triglycerides, individual phospholipids, free fatty acids, and their acyl group compositions. In vivo and in vitro effects of ethanol will be examined in heart tissue mince, sarcoplasmic reticulum and mitochondria. Lipid-metabolizing enzyme activities to be examined include deacylation-recylation enzymes and lysophospholipase. These biochemical studies will help to elucidate the underlying biochemial mechanisms of ethanol insult to cardiovascular tissues.