Study Of The Effects Of Enriched L-Arg And Ala-Gln Dipeptiven TPN On Treatment Ischemia/Reperfusion Injure Of Transplanted Small Bowel In Rats

In small bowel transplantation(SBT), the graft mucosa is much sensitive to ischemialreperfusion injure and impairment will likely occur which intensifies with time. Besides, long-term total parenteral nutrition (TPN), which is necessary for supporting functional recovery of early stage SBT, will also lead to mucosal injury and bacterium translocation and thus tamper the recovery process. It has been well-documented that L-Arg can improve NO level and NO is supposed to protect the transplanted small bowel from mucosal injury and thus facilitate its functional recovery. As well-known necessary for cell metabolism of gut tract, Gin plays vital roles in integrity maintenance and injury repair of intestinal mucosa. This study was conducted to investigate the theraputic and synergetic effects of L-Arg and Gin in ischemia!reperfiision injure of graft. Methods: Ischemia/reperfusion injure model in rat SBT was previously established.The present study includes of two parts. In part 1,32 SD rats were randomly divided into two groups: controi(n=1 6) and SBT(n=1 6). The animals were sacrificed at 20 minutes after reperfusion and 1 day after operation. In part 2, 112 SD rats were randomly divided into 4 groups: 1), the control group(control, n=16) underwent suppositional operation; 2), SBT+standard TPN group(sTPN, n=2 X 16); 3), SBT+ Ala-Gin Dipeptiven +TPN group (dTPN, n=2 X 16); 4), SBT+L-Arg + Ala-Gin Dipeptiven +TPN group(aTPN, n=2 X 16). The rats were sacrificed 4 and 8 days postoperation to measure Gin level in serum and mucosai NO, MDA, GLN content and histological changes. Results: 1), Graft mucosal MDA increased to a significant level (P<0.01) in 4 comparison with the control immediately after blood reperfusion and began to decrease gradually thereafter. Normal level was seen 8 days in the sTPN group and dTPN group and 4 days in the aTPN group postoperation. 2), The graft mucosai NO content decreased immediately after 20 minutes of reperfiision in SBT group,and lower than control group(P<0.0l), resumed normal 1 day later. 4 and 8 days after operation, mucosal NO levels were nomal in sTPN group and dTPN group but still higher than control group in aTPN group(P拁zO.0l, P<0.O 1). 3), serum and mucosal Gin level, vilius height and mucosal thickness were all greater in dTPN group and aTPN group than in sTPN group, indicating that Ala-Gin Dipeptiven accelerated the regenerating process of graft mucosa. 4), Mucosal Gin Ievel(P<0.05) and villus height(P<0.05) were higher in aTPN group than in dTPN group at day 4 after operation but almost the same at day 8. Conclusion: 1), Ala-Gin Dipeptiven can maintain and improve serum and graft mucosal Gin level. 2), Ala-Gin Dipeptiven application during TPN can help repair graft mucosa. 3), L-Arg can improve the serum and graft mucosa NO level. 4), L-Arg is synergetic to the mucosal- recovery- stimulating activity of Ala-Gin Dipeptiven.