The role of endothelin and its relationship with nitric oxide (NO) production in ischemia-reperfusion associated with pancreas transplantation has been explored. For this purpose, pancreatic levels of endothelin were evaluated in an experimental model of pancreas transplantation after different periods of cold preservation. The effects of NO synthase inhibition were also evaluated. Results show posttransplantation increases in lipase and endothelin production. The release of lipase and endothelin was only prevented by NG-nitro-L-arginine methyl ester after a short ischemic period. Thus, endothelin synthesis could be a consequence of stimulation with NO in the ischemiareperfusion associated with pancreas transplantation.