Abstract:Objective:To investigate the effect of inducible nitric oxide synthase inhibitor aminoguanidine on transplanted pancreas in rats.
Methods :The models of pancreas transplantation were established in 30 rats.The streptozotocin induced diabetic male Wistar rats were randomly assigned to 3 groups: (1) Blank control group(n=6), the rats underwent shamsurgery; (2) transplant control group (n=6), the rats received pancreas transplantation only; (3) aminoguanidine group(AG group) (n=18), aminoguanidine (a dose of 60, 80, or 100 mg/kg weight) was added to the intravascular infusion before reperfusion of the transplanted pancreas. At 4h after reperfusions, serum nitric oxide（NO） level, blood sugar, and amylase activity were detected. cNOS and iNOS activity of pancreas were detected Pancreas sections were evaluated by light microscopic examination with HE staining and immunohistochemistry staining.
Results:As compared with transplant control group, the serum NO level and amylase activity decreased significantly, and pancreas injury was much less in AG groups, especial in AG-80 mg/kg sub-group showed the most significant difference（P＜0.01）.The expression and activity of tissue iNOS activity, and blood sugar in AG-80 mg/kg sub-group were much lower than those in transplant control group（P＜0.01）.
Conclusions:Selective iNOS inhibitor-aminoguanidine has protective effect on the transplanted pancreas in rats. The possible mechanisms may be inhibition of overproduction of NO, and reduction the cytotoxicity as free radicals of NO.