Effects of glutamine on intestinal permeability and bacterial translocation in TPN-rats with endotoxemia.

Abstract

To evaluate the protective effect and mechanism of glutamine on the intestinal barrier function in total parenteral nutrition (TPN) rats with trauma or endotoxemia. To perform prospective, randomized and controlled animal experimentation of rats with surgical trauma, TPN and endotoxemia, thirty-four male, adult Sprague Dawley rats were divided into four groups: control group (n=8), TPN group (n=9), trauma and endotoxemia group (LPS, n=8) and trauma plus endotoxemia supplemented with glutamine in TPN solution group (Gln.group, n=9). All groups except the control group were given TPN solutions in 7-day experimental period. For Gln group, 1 000 mg/kg/d of glutamine was added to TPN solution during day 1-6. On the 7(th) day all the animals were gavaged with lactulose (66 mg) and mannitol (50 mg) in 2 ml of normal saline. Then 24 h urine with preservative was collected and kept at -20 degrees. On day 8, under intra-peritoneal anesthesia using 100 mg/kg ketamin, the intestine, liver, mesenteric lymph nodes and blood were taken for examination. The body weight of LPS group decreased most among the four groups. The structure of small intestinal mucosa in TPN group, LPS group and Gln group showed impairments of different degrees, and the damage of small intestinal mucosa in Gln group was remarkably alleviated. The concentrations of interleukins in small intestine mucosa were lower (for IL-4 and IL-6) or the lowest (IL-10) in Gln group. The IgA level in the blood plasma and the mucosa of Gln group was the highest among all of the groups. The urine lactulose/mannitol test showed that the intestinal permeability in LPS group was lower than that in TPN group (P<0.001), but there was no difference between LPS group and Gln group. The rate of bacterial translocation in Gln group was lower than that in LPS group (P<0.02). Prophylactic treatment with glutamine could minimize the increments of intestinal permeability and bacterial translocation caused by trauma and endotoxemia in rats treated with TPN.