Metabolism of hepatic and plasma triglycerides in rabbits given ethanol or ethionine.

The formation and transport of hepatic triglyceride fatty acids (TGFA) were studied after intravenous administration of palmitate-1-(14)C or palmitate-9,10-(3)H in rabbits pretreated with ethanol or ethionine. Administration of ethanol produced significant hypertriglyceridemia without consistent accumulation of hepatic fat. The isotopic studies suggest that plasma free fatty acids were the major precursors of TGFA in d < 1.006 lipoproteins and that fatty acids synthesized in the liver were not the source of the hypertriglyceridemia in the ethanol-treated animals. Administration of ethionine resulted in an increased concentration of TGFA in the liver, a decreased level of TGFA in d < 1.006 lipoproteins and a very low specific activity in this plasma fraction. These findings suggest that the development of fatty liver after administration of ethionine is in part accompanied by impaired release of TGFA from the liver.