Free amino acid levels in muscle and liver of a patient with glucagonoma syndrome

Abstract

This study set out to measure the amino acid concentrations in the femoral artery, femoral vein, hepatic vein, muscular and hepatic tissue, and urine of a patient with the glucagonoma syndrome. The total plasma amino acid concentration was severely reduced on admission (737 μmol/L, 26% of normal), with only a slight increase during intravenous administration of 200 g of amino acids per day. The total intracellular amino acid levels in the muscle were 86%, and those of the liver were 47% of the normal range. Only 0.62% of the amino acids administered were found in the urine. Arteriovenous amino acid concentration differences across the muscle and splanchnic tissue indicated the release of amino acids (mainly glutamine, glycine, and alanine) from the muscle and the absorption of amino acids by the splanchnic bed. This study shows that the infusion of a high amount of amino acids cannot increase the subnormal plasma AA levels of patients with the glucagonoma syndrome. the low total plasma AA levels are paralleled by decreased intracellular free amino acid levels in the muscle and liver.