Functional Changes Of Endocrine And Exocrine Cells Between Pancreatic Duct Ligation In Mice And The Pancreatic Duct Dilatation In Human

Purpose:The endocrime changes of islet cells in the vicinity of expansion pancreatic will be studied by mice pancreatic duct selective ligation, observing the form and function change of mice islet endocrine cells, and collecting the surgical specimens of patients with clinical human pancreatic duct dilatation whipple surgery. By comparing the two results above, similarity of human and rodent pancreatic islet cell proliferation changes will be explored, which can provide new ideas for the future research.Methods: 1、In this study, Male C57B1/6mice (8weeks old) were uesd as the experimental animals, and22mice were randomly divided into the pancreatic duct ligation(PDL) group and sham operation group.The general changes of the pancreas and the histopathological changes of endocrine and exocrine cells were observed and compared in1month,2months after the operation. The immunofluorescence staining on a series of specific antibodies were done according to biological characteristics of the endocrne cells, and especially to the biological characteristics of βcells. All the mice were administered an injection of Brdu (50mg/kg)24hours before euthanasia.2、The specimen of patients after whipple operations whose pancreatic duct expanded for its blockage caused by various diseases were used as the study objects.60specimens of patients after whipple operations whose pancreatic duct expanded were collected randomly. The form and function change of islet cells in the vicinity of expansion pancreatic were studied by immunofluorescence staining on a series of specific antibodies.All the images were processed by image analysis software Image Pro Plus6.0. The statistical results were expressed as mean±D. SPSS15.0was used for statistical analysis of the data, and p<0.05was considered to be statistically significant.Results:One month after the PDL,comnpare to the control group,the pancreas weight of mouse is decreased significantly, the experimental group and control group there was a significant difference (P<0.05), respectively,115.40±1.14mg The.34.40±1.14mg. One month after the PDL, the volume of pancreas is shrink, exocrine tissue disappear, and replaced by adipose tissue and duct-like tissue; Two months after the PDL,fatty tissue and fibrous connective tissue replacement, which were around the islet and the main pancreatic duct. However, endocrine tissue had no significant morphological changes pathologically in each stage. One month after the PDL, the positive rate of islet cell proliferation compared with control group significant difference (P<0.05), the experimental group and control group were7.3%±1.3%.0.15±0.15%.Two months after the PDL,the positive rate of islet cell proliferation compared with control group significant difference (P<0.05), the experimental group7.5±1.0%,0.20%±0.23%.Among60cases of human clinical trials specimens whipple patients we found18cases of islet cell hyperplasia, while others with no proliferation-positive cells.Conclusion:Mice (3-cell proliferative capacity increased after their pancreatic duct liagtion (PDL) for a long term. But no obvious change was found in the islet cell morphology. The experiment results showed that human pancreatic duct abstruction can promote islet (3-cell hyperplasia,but the effect was not so obvious as in mice.The comparative study of β cell regeneration between animal and human still needs further research.