Amino acid and α-keto acid concentrations in plasma and blood of the liverless dog

Abstract

The plasma unbound amino acid concentrations and the blood concentrations of pyruvate, α-ketoglutarate, lactate, and the α-keto analogues of leucine plus isoleucine plus valine were determined in hepatectomized dogs. The concentrations of leucine, isoleucine, valine, α-amino-n-butyric acid, methionine and the α-keto analogues of leucine plus isoleucine plus valine decreased after hepatectomy. When leucine, isoleucine, valine, α-ketoisocaproic acid, α-ketoisovaleric acid, and/or methionine were infused intravenously in the liverless dog, the major portion of these compounds was found to be taken up by the tissues. The concentrations of all amino acids except leucine, isoleucine, valine, α-amino-n-butyric acid, and methionine increased after hepatectomy. Pyruvate, α-ketoglutarate, and lactate concentrations rose immediately after hepatectomy and remained generally elevated throughout the survival of the liverless animal. The lactate-to-pyruvate ratio was the same in the preoperative and postoperative animals.