Brain amino acids measured by intracerebral dialysis in portacaval shunted rats.
Changes in brain amino acid uptake and metabolism have been proposed as a possible etiological factor in hepatic encephalopathy. By use of a brain dialysis technique (a thin tube implanted in the brain of the living animal), the extracellular amino acid concentrations in the striatum of portacaval (PC)-shunted and sham-operated rats were measured. Leucine, phenylalanine, methionine, and glutamine were increased two- to sixfold in the PC-shunted rats, whilst no changes were seen for GABA, valine, glutamate, or isoleucine, confirming previous reports. Aspartate levels were 350% higher in the PC-shunted rats, and this rise, as well as that of phenylalanine, was significantly correlated with the lower motor activity observed in the PC-shunted rats, suggesting a possible importance of these amino acids in the etiology of hepatic encephalopathy. The amino acid concentrations measured in whole blood demonstrated the well-known pattern of low levels of branched-chain amino acids and increased concentrations of phenylalanine, glutamine, and histidine.
D000596:Amino Acids / Q000097:blood / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism*; D003956:Dialysis; D006501:Hepatic Encephalopathy / Q000378:metabolism; D008297:Male; D009043:Motor Activity; D011167:Portacaval Shunt, Surgical; D051381:Rats; D011919:Rats, Inbred Strains
D000596:Amino Acids