Effect of dietary protein and GABA on food intake, growth and tissue amino acids in cats.
GABA at 5%, but not 3%, of a low protein diet depressed food intake and growth of kittens. Adaptation to high protein prevented these effects. When cats adapted to low or high protein were fed a meal containing GABA, plasma GABA concentration after 2 hr was 8-fold higher in the low than in the high protein group; clearance was almost complete within 6 hr. Concentrations of proline, branched-chain, other large neutral and basic (especially ornithine) amino acids increased more when cats were fed a high rather than a low protein meal; glycine decreased. At 6 hr, concentrations had consistently returned to initial levels only in the low protein group. Feeding the high protein diet ad lib increased tissue concentrations of threonine, proline and the branched-chain amino acids. Hepatic or renal GABA-aminotransferase activity was not altered in kittens fed the high protein diet. Kidney activity was 10-fold that of liver, which may contribute to the better tolerance of GABA by cats than by rats.
D000612:4-Aminobutyrate Transaminase / Q000378:metabolism; D000596:Amino Acids / Q000032:analysis*; D000818:Animals; D001921:Brain / Q000201:enzymology; D001923:Brain Chemistry / Q000187:drug effects; D002415:Cats; D004044:Dietary Proteins / Q000494:pharmacology*; D004435:Eating / Q000187:drug effects*; D005260:Female; D006128:Growth / Q000187:drug effects*; D007668:Kidney / Q000032:analysis / Q000201:enzymology; D008099:Liver / Q000032:analysis / Q000201:enzymology; D008297:Male; D005680:gamma-Aminobutyric Acid / Q000097:blood / Q000494:pharmacology*
D000596:Amino Acids; D004044:Dietary Proteins; D005680:gamma-Aminobutyric Acid; D000612:4-Aminobutyrate Transaminase