Enteral glutamine modulates renal glutamine utilization.
Enteral glutamine feeding effect on renal glutamine utilization was assessed from the perspective of gamma glutamyltransferase activity-dependent cellular glutamate modulation of phosphate-dependent glutaminase. After 4d, rats fed an elemental diet supplemented with glutamine exhibited a 2 1 % higher kidney glutamate content and 27% reduction in ammonium excretion, both P < 0.05. Glutamine removal from plasma was depressed 62% in the glutamine-fed group (324 +/- 155 vs. 780 +/- 154 nmol x min(-1) x 100 g body weight (-1), P < 0.05) despite an elevated arterial plasma glutamine load delivered to the kidney. Administration of acivicin, 36 mg/kg body weight, to glutamine-fed rats inhibited gamma glutamyltransferase > 90% and decreased kidney glutamate content 42%. This reduction in kidney glutamate was associated with a 3.3-fold enhancement in both glutamine extraction (474 +/- 184 to 1548 +/- 255 nmol x min(-1) x 100 g body weight (-1)) and ammonium excretion (295 +/- 30 to 978 +/- 96 nmol x min(-1) x 100 g body weight(-1)), both P < 0.01. These findings are consistent with enteral glutamine regulation of renal glutamine utilization through an elevation of the cellular glutamate level.
Welbourne
T
T
Department of Physiology, Louisiana State University Medical Center, Shreveport, LA 71130, USA.
Mu
X
X
Evans
S
S
D000818:Animals; D004750:Enteral Nutrition; D005973:Glutamine / Q000008:administration & dosage / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D005723:gamma-Glutamyltransferase / Q000502:physiology
D005973:Glutamine; D005723:gamma-Glutamyltransferase