The effect of glutamine-supplemented total parenteral nutrition on nutrition and intestinal absorptive function in a rat model.

The aim of the present study was to evaluate the effect of short-term (7 days) glycyl-glutamine-supplemented total parenteral nutrition (TPN) on nutrition and intestinal absorptive function in a rat model. Thirty Wistar rats, weighting 140-180 g, were divided into three groups (n=10) randomly. The animals received isonitrogenous and isocaloric TPN solutions for 7 days. The nitrogen was supplied by glycyl-glutamine dipeptide-supplemented amino acid solution (group G), and two standard amino acid solutions (group V, group N), respectively. Body weight, plasma glutamine level, nitrogen balance, total tissue water and intestinal absorptive function, assessed by (15-N)-glycine absorption, were investigated. Body weight decreased in three groups at the end of TPN; there was no significant difference in relative body-weight changes. There was a significant improvement of cumulative nitrogen balance and nitrogen retention in group G compared to other groups (P<0.05). There was no significant difference in intestinal glycine absorption (P>0.05) among the three groups. Total tissue water of left thigh muscle was significantly higher in group V and group N than that in group G (P<0.05). The results indicated that short-term (7 days) TPN supplemented with glycyl-glutamine improved plasma glutamine level and nitrogen balance, decreased water content of muscle, but had no beneficial effect on absorptive function in a rat model.