Changes in cerebrospinal fluid and plasma amino acid concentrations with elevated dietary protein concentration in dogs with portacaval shunts

doi:10.1016/0024-3205(91)90335-9

Life Sciences

Volume 48, Issue 23, 1991, Pages 2215-2223

https://doi.org/10.1016/0024-3205(91)90335-9 Get rights and content

Abstract

Effects of dietary protein concentration on plasma and cerebrospinal fluid (CSF) amino acids (AA) in dogs with portacaval shunts (PCS) were examined. An 18% protein purified diet (18P) was fed to 4 PCS dogs and 2 controls; at week 10, 2 of the PCS dogs were switched to 36% protein (36P) until week 28. Effects of the diet switch on plasma and CSF AA in 8 normal dogs were determined in another experiment. Neither surgery nor protein level significantly affected average food intake (weeks 10–28). Plasma amino acid patterns typical of PCS animals were observed: phenylalanine and tyrosine increased and branched chain AA decreased with shunting (p<0.05). Plasma phenylalanine increased further with 36P in PCS dogs (p<0.05), but was not affected by dietary protein concentration in controls. With 36P: CSF arginine, serine, histidine, tryptophan, phenylalanine, glutamate and glutamine increased in PCS dogs; but only arginine decreased in CSF of controls (p<0.05). In PCS dogs, significant CSF AA changes with elevated dietary protein were unrelated to plasma AA changes.

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^☆: Supported in part by Biomedical Research Support Grant RR05457.

²: Dr. Schaeffer was recipient of the American Association of University Women Education Foundation Program Anita S. Miller Endowed Fellowship, and is corresponding author: USDA, ARS, Western Human Nutrition Research Center, P. O. Box 29997, San Francisco, CA 94129.

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Changes in cerebrospinal fluid and plasma amino acid concentrations with elevated dietary protein concentration in dogs with portacaval shunts☆

Abstract

Lancet

Lancet

Am. J. Surg.

Am. J. Clin. Nutr.

Lancet

Lancet

Lancet

Gastroenterology

Gastroenterology

Am. J. Clin. Nutr.

J. Surg. Res.

Am. J. Clin. Nutr.

J. Surg. Res.

J. Clin. Invest.

Surg. Forum

Am. J. Dig. Dis.