[Alcohol induced changes of amino acid metabolism].

The effects of ethanol upon amino acid metabolism represent a complex interaction of ethanol metabolism and its products, nutritional abnormalities and pathological alterations in various organs especially the liver. The effects of chronic alcohol consumption upon amino acid absorption, digestion and transport appear largely of theoretical interest without significant impact on nitrogen balance, hepatic urea or protein synthesis or plasma amino acid patterns. Marked alterations in amino acid metabolism in the liver and other organs are observed in human alcoholics. These result in changes in plasma and tissue levels of amino acids and may explain or contribute to hepatic encephalopathy by altering levels of intermediate products such as catecholamines and neurotransmitters. Plasma amino acid changes due to ethanol may also provide a biochemical marker for the assessment of ethanol consumption in an objective fashion. Amino acid requirements in the diet may be altered in the alcoholic along with lowered protein tolerance. Administration of selected proteins or mixtures of amino acids may provide a means for maintaining nitrogen balance while avoiding or improving hepatic encephalopathy in such patients.