Pancreatic glucagon-like immunoreactivity in a pancreatectomized patient

True or 'pancreatic' glucagon-like immunoreactivity (GLI) was found in the plasma of a pancreatectomized patient. In contrast with the regulation of pancreatic GLI in normal controls, there was paradoxical release after oral glucose, no response to arginine or insulin-hypoglycaemia and somatostatin did not suppress its release, but tolbutamide did. Similar to controls, this pancreatic GLI appeared to be under adrenergic beta-receptor control. There was no apparent effect on blood glucose regulation despite marked changes in pancreatic GLI levels during the various manipulations. On polyacrylamide gel electrophoresis, pancreatic GLI from our patient's plasma eluted as two equivalent peaks: one with the glucagon marker and the other in a more cathodal position. We therefore suggest that, although the extra-pancreatic 'pancreatic' GLI in our patient's plasma has immunologic similarities with pancreatic glucagon, the responses to stimulation and suppression are quite different from those in controls and the biologic activity does not appear to be that of pancreatic glucagon.