OBJECTIVETo investigate the effects of epidermal growth factor(EGF) on mucosal structure after small bowel transplantation in rat.

METHODSTotal small bowel transplantation was performed in inbred Wistar(RT1k) rats heterotopically, either total parenteral nutrition(control group, n=10) or TPN supplemented with epidermal growth factor(EGF group, n=10) was given to the recipients from the second day to 10th day after operation. The changes of morphology, ultrastructure, mucosal protein and DNA contents were determined.

RESULTSThe height of mucosal villus,the depth of crypt, the thickness of mucosa and the surface area of villus were (284.47+/-31.58)microm, (98.78+/-10.83 microm, (389.56+/-31.72)microm and (0.089+/-0.009 )mm(2) respectively in EGF group,and (176.45+/-14.62)microm, (74.45+/-8.34)microm, (259.38+/-24.65) microm, and (0.041+/-0.005)mm2 respectively in the control group. The morphological parameters were significantly higher in EGF group than those in the control group. Mucosal protein content was (84.65+/-8.32)mg/g wet wt in EGF group,significantly higher than (53.73+/- 11.45) mg/g wet wt in the control group(P=0.012). DNA content was also significantly higher in EGF group than that in the control group. [(0.86+/0.10)mg/g wet wt vs (0.51+/-0.06)mg/g wet wt, P=0.008]. Nearly normal ultrastructure of the graft enterocyte was maintained in EGF group, while atrophic microvilli and broken mitochondrial crista were observed in the control group.

CONCLUSIONEGF can preserve the mucosal structure of the graft, maintain the integrity of the ultrastructure of graft enterocyte after small bowel transplantation in rat.