Hepatic amino acid levels in rats after long-term ethanol feeding

Abstract

Male Wistar rats were given ethanol to provide 25–33 per cent of the total calories consumed. Control rats were pair-fed either sucrose or lipid. The experiments lasted for 5–9 weeks. In experiment A protein constituted about 15 per cent of the calories and all diets were given until the moment of sacrifice. In experiment B the same diets were fed to similar groups of animals, but a control diet was given to all three groups as the only food the last day before death. Protein provided 10 per cent only of the total calories in this experiment due to a higher intake of ethanol. In experiment C the protein content of the basic diet was enhanced and both ethanol and control rats covered about 25 per cent of their caloric demands by protein. In this experiment, too, a control diet was given to both groups the last day before sacrifice. Long-term ethanol feeding reduced the incorporation of intraperitoneally injected 14C-labelled valine into hepatic protein in all three feeding models. There were, however, no consistent changes in the concentrations of the individual hepatic amino acids when ethanol treated and control rats were compared. It is concluded that reduced hepatic protein synthesis accompanying long-term ethanol consumption is not a direct consequence of lack of a single or several amino acids, and that moderate to severe consumption of ethanol does not disturb the normal pattern of free amino acids in the rat liver.