Effects of nitric oxide on rat pancreas transplantation

The aim of this study is to clarify relationships between tissue nitric oxide(NO)and transplanted pancreas functions. Forty eight syngeneic rat pancreas transplantations were performed and they were assigned two groups as follows : (I) Fresh group, which were transplanted within 1-hr after harvesting. (II)Preserved group, transplanted after 24-hr preservation in 4 degrees C with University of Wisconsin solution. The recipients of the two groups were treated with the following agents before organ revascularization : group 1, normal saline(2 ml/kg); group2, N-G-nitro-L-arginine methyl ester (L-NAME, 20mg/kg); group 3, L-NAME (20mg/kg) with supplemental L-arginine (Arg, 400mg/kg). Tissue NO(NO2- + NO3-)levels in the graft(measured by chemiluminescence detector), tissue blood flow (by laser doppler flowmetry), K value of intravenous glucose tolerance test, and graft oedema were measured at 6-hr after transplantation. All recipients became normoglycemic (less than 120mg/dl) after transplantation. In both Fresh and Preserved groups, administration of L-NAME caused significant decrease in tissue NO levels, tissue blood flow, and K value. However graft oedema increased in Preserved group, but not changed in Fresh group. Administration of supplemental Arg, compared with L-NAME alone, improved tissue NO levels, tissue blood flow, and K value in both groups, but graft oedema in Preserved group was not significant. These results suggest favorable effects of nitric oxide on transplanted pancreas functions.