The Study Of Effect And Value Of RYGBP Operation On The Blood Glucose And Proliferation And Differentiation Of Pancreatic Progenitor Cell Of None-obese Diabetic Mice

ObjectiveTo investigate the effect of Roux-en-y gastric bypass on blood glucose in STZ (streptozotocin) induced diabetic mice,the changes of pancreatic progenitor cell in this progress.To explore the relationship between declination of blood glucose and variation of pancreatic progenitor cell and the relationship between declination of blood glucose and changed body mass.MethodsWe produce a none obese diabetic model on mature C57BL/6 mice by peritoneal injection of STZ(200mg/kg),40 diabetic mice were allocated into three groups randomly:16 in GBP group(DMOP),16 in shame operation group(DMFOP) and 8 in untreated control group(DM).On the same time,3 normal mice control groups were set:8 for GBP group(NOP),8 in shame operation group(NFOP) and 8 for untreated group(N).Operations were performed on the mice of DMOP and DMFOP groups ten days after injection of STZ.Blood glucose were measured on all mice before and 1 week,2 weeks,3weeks,4weeks,5weeks,6weeks after operation and body weight were measured simultaneously.Hypoglycaemia and hyperglycaemia mice were picked out from DMOP group on 1st,2nd,3rd and 4th week after the process,on the other hand,one of mice were selected from each group of DMFOP,DM,N,NFOP and NOP on the 4th week randomly.They were all sacrificed to characterize the pancreatic morphological changes.We performed immunohistochemical and HE analysis on the tissue sections.Results 1.Comparing with preoperation and DM or DMFOP control group,random blood glucose of mice were reduce significantly post operation.The declination of blood sugar sustained more than 6 weeks after operations(till the end of experimental investigations).2.Perioperative mortality was different between DMOP(2/16) and DMFOP(15/16) group.3.HE staining showed that,in the DMOP group,insular morphous were similar to normal on 4th week post operation.At the same time,we found many newly small islets around pancreatic ducts and some of them consist of only one,two or three insulin positive cells.4.Discovery from immunofluorescence staining:by simultaneous insulin and glucagon cell detection,(GLU+/INS+) double expression cell could be found in some islets,so far,coexpression of insulin and glucagon were regarded as a index of premature endocrine precursor cell.Ngn3 positive cells dispersed in the pancreas were dectected.Ngn3 is one of markers from endocrine progenitor cell.Conclusion1.GBP can markedly reduce plasma glucose in diabetic mice.2.GBP can promote the regeneration of islets of pancreas.