ObjectiveTo study the protective effect of hepatocyte growth factor(HGF) on grafted mucous membrane of transplanted small bowel.MethodsTotal small bowel transplantation was made in inbred Wistar (RT1k) rats heterotopically,either total parenteral nutrition (control group,n=10) or hepatocyte growth factor supplemented TPN (HGF group,n=10) was given to the recipients from the 2nd day to the 10th day postoperatively. Morphological parameters of the transplanted intestinal mucosa, such as mucosal villous height, villous width, crypt depth, mucosal thickness and villous surface area were observed. Variation of ultrastructure of transplanted epithelial cells was observed. Composition of mucosal protein and DNA content were tested. ResultsComparison between HGF group and the control group were as follows. Mucosal villous height (298.79±22.31） μm vs （176.45±14.62） μm, P=0.001, villous width (107.46±12.34） μm vs （74.20±16.85） μm, P=0.004, crypt depth (104.56±11.17） μm vs （74.45±8.34） μm, P=0.000 5, mucosal thickness (409.53±35.83） μm vs （259.38±24.65） μm, P=0.003, and villous surface area (0.101±0.011) mm2 vs (0.041±0.005) mm2, P=0.001 were found significantly increased in HGF group compared with control group, there were no obvious difference decrease as compared to pretransplant parameters.Mucosal protein composition was higher in HGF group than that in control group （89.65±9.28) mg/g wet wt vs (53.73±11.45) mg/g wet wt, P=0.012, baseline (92.64±10.52) mg/g wet wt, nearly equal to baseline; DNA composition was also high in HGF group （0.89±0.09) mg/g wet wt vs (0.51±0.06) mg/g wet wt, P=0.008, baseline (0.91±0.09) mg/g wet wt. Nearly normal ultrastructure of the graft was maintained in HGF group, atrophied microvilli and broken mitochondrial crista were observed in control group.ConclusionHepatocyte growth factor can improve mucosal structure, preserve enterocyte ultrastructure of isograft after small bowel transplantation in rat.