Can a glutamate-enriched diet counteract glutamine depletion in endotoxemic rats?

The study evaluated whether a glutamate-enriched diet would restore glutami ne tissue pools and maintain tissue trophicity in endotoxemic rats. For thi s purpose, young male Sprague-Dawley rats received an intraperitoneal injec tion of lipopolysaccharide (LPS) from Escherichia coli at 3 mg/kg body weig ht. After 24 hours of food deprivation, the rats were enterally refed for 4 8 hours using Osmolite(R) enriched with glutamate at 4 g/kg/d (LPS-Glu grou p, n = 7) or glycine isonitrogenous to glutamate (LPS-Gly group, n = 7). A control group (healthy group, n = 7) had free access to a standard rodent d iet. Tissue weights and protein contents were significantly lower in both L PS-treated groups than in the healthy group. No plasma or tissue accumulati on of glutamate was observed except in the liver. Glutamine concentrations were increased in the jejunum, liver, and plasma in the LPS-Glu group versu s the other two groups (P < 0.05). Conversely, they were depleted in muscle s of the endotoxemic groups versus the healthy group (P < 0.05). Villus hei ght was significantly greater in the LPS-Glu group than in the LPS-Gly grou p in the jejunum (P < 0.05), but not in the ileum. in conclusion, a glutama te-enriched diet administered enterally to endotoxemic rats can counteract glutamine depletion in the splanchnic area but not in muscles. In addition, glutamate displayed a trophic effect restricted to the jejunum. (J. Nutr. Biochem. 10:331-337, 1999) (C) Elsevier Science Inc. 1999. All rights reser ved.