IMPROVEMENT OF STRUCTURE AND FUNCTION IN ORTHOTOPIC SMALL-BOWEL TRANSPLANTATION IN THE RAT BY GLUTAMINE

Significant atrophy and impaired absorption occur in the heterotopical ly transplanted small intestinal isograft, and these deficits are corr ected when the preferred fuel of the enterocyte, glutamine (Gln), is s upplemented to total parenteral nutrition (TPN). In the orthotopic sma ll bowel isograft, this study determined whether Gln-enriched TPN enha nced mucosal structure and function, and decreased bacterial transloca tion to mesenteric lymph nodes (MLN). Seventeen adult Lewis rats recei ved orthotopic jejunal isografts and central venous catheters for TPN. Rats received either TPN with 2% Gln or the same TPN with isonitrogen ous balanced nonessential amino acids for 10 days. Eight normal, chow- fed rats served as baseline controls. Mucosal villous height, surface area, crypt depth, weight, protein and DNA contents, brush border enzy mes, C-14 glucose absorption, and bacterial translocation to MLN were evaluated in both the graft and host jejunum and the control animals. Gln-enriched TPN significantly increased mucosal villous height (P<0.0 1), surface area (P<0.01), and glucose absorption (P<0.01), and it red uced bacterial translocation (P<0.05) when compared with the non-Gln T PN group. For most study variables, there were no significant differen ces between Gln-enriched TPN or baseline and between the graft and hos t jejunum for Gln- and non-Gln-supplemented animals. There were no sig nificant differences in DNA content and brush border enzymes among gro ups. These results indicate that Gln-enriched TPN improves mucosal str ucture and glucose absorption and reduces bacterial translocation to M LN in the orthotopic small bowel isograft.