Experimental Study Of Survival Rate And Functi-on Of The Stomach Subserous Transplanted Islets In Inbred Rats

BackgroundIslet transplantation is the most likely method to cure type1diabetes. Since the advent of the "Edmonton" protocol, the short-term effect of islet transplantation has greatly improved while its long-term effect is poor with its five-year survival rate less than10%. In1972, Ballinger and Lacy first reported that transplanting islets into the liver via the portal vein could achieve absolutely relief of diabetes in rats. Soon after several other sites such as anterior chamber, testis, muscle, omentum were also detected whether they could be served as the transplanted site or not. After review of the literature, no study associated with the islets transplanted into the stomach subserous space was found.ObjectiveThe present study was to explore the feasibility of transplanting islets into the stomach subserous space in diabetic inbred rats and to describe the skills associated with the procedures, the outcomes after transplantation as well.MethodsLewis inbred male rats were enrolled as islets donors and recipients. Diabetes was induced by the administration of streptozotocin (STZ). Equal numbers of fresh islets were transplanted into the stomach subserous space, the renal subcapsular space, and the portal vein, respectively. The glucose level, intraperitoneal glucose tolerance and survival rate of islets transplanted were detected afterwards.ResultsThe glucose level of all diabetic rats receiving islets in stomach subserous or renal subcapsular space significantly decreased3weeks after transplantation (P<0.05). All rats had good glucose tolerance, and there was no significant difference in the glucose level between the two groups (P>0.05). The islets transplanted into those two sites were identified by immunohistochemical detection using anti-insulin antibody, with a few of inflammatory cells infiltrating around the islets. The infiltration was more obvious around islets located in the renal subcapsular space. The glucose level of rats with islets transplanting into renal subcapsular space and stomach subserous space gradually increased again4and5weeks after transplantation, respectively. The glucose level of all the rats in the two groups significant increased with a reduced glucose tolerance and the immunohistochemical detection showed that there were only dispersed islets left in the two sites6weeks after transplantation. While in the portal vein group, on improvement in the glucose of diabetic rats and no available islets in the liver were found during the follow-ups.ConclusionsIslet transplantation into stomach subserous space is technically feasible and owns a better effect in improving the glucose of diabetic rats than that into renal subcapsular space in the early state. However, the long-term effects remain to be confirmed by other studies. No significant improvement in glucose of diabetic rats was found with a limited amount of islets transplanting into the portal vein, compared to the other two sites.