Glutamine supplemented parenteral nutrition prevents intestinal ischemia- reperfusion injury in rats

AIM: To examine whether glutamine prevents the injury to the intestinal mucosa after intestinal ischemia-reperfusion (I/R) in rats. METHODS: Thirty male Sprague-Dawley rats were randomly divided into 3 groups: a standard parenteral nutrition (PN) group (n = 10); an I/R-PN group (n = 10); an I/R-glutamine enriched PN (I/R-Gln) group (n = 10). The superior mesenteric artery (SMA) was clamped. After 60 min of ischemia, reperfusion was initiated and infusion was started. All rats received isocaloric and isonitrogenous nutritional support for 48 h. Spleen, liver, mesenteric lymph nodes (MLN), and intestinal segments were removed for morphological and biochemical analyses, and blood samples were collected for bacterial culture and measurement of endotoxin levels. The permeability of intestinal mucosa was assayed by measurement of D-(-)-lactate levels in plasma. RESULTS: In I/R-PN group, extensive epithelial atrophy was observed, mucosal thickness, villous height, crypt depth and villous surface area were decreased significantly compared with PN group, whereas these findings did not occur in the I/R-Gln group. The incidence of intestinal bacterial translocation to spleen, liver, MLN, and blood was significantly higher in I/R-PN group than that in other groups. Plasma endotoxin levels significantly increased in the I/R-PN group compared with the I/R-Gln group. Remarkably higher values of D-(-)-lactate were also detected in PN group compared with that in I/R-Gln group. CONCLUSION: Glutamine protects the morphology and function of intestinal mucosa from injury after I/R in rats.