Pancreatic endocrine function in experimental pancreatolithiasis in dogs.

In attempt to clarify changes of pancreatic endocrine function in human calcified pancreatitis at its earlier stages, an experimental model of pancreatolithiasis comparable to the human disease was produced in six dogs after incomplete ligation of the major pancreatic duct. Endocrine function was serially examined by intravenous glucose (0.5 g/kg) tolerance test and insulin (0.5 U/kg) tolerance test before and 3, 6, and 12 months after the duct ligation. Neither alpha nor beta cell dysfunction became apparent until 12 months after the ligation. The disappearance rate of glucose in an intravenous glucose tolerance test decreased from 2.92 +/- 0.41 (mean +/- SE) of the preligation value to 1.58 +/- 0.17%/min at the end of the 12 months period (p less than 0.02). Plasma insulin response to glucose was also reduced significantly. Although hypoglycemia induced during an intravenous insulin tolerance test was maximal in the 12th month, distinct response of plasma pancreatic glucagon to the hypoglycemia disappeared. Endocrine insufficiency of the pancreas observed in this experimental model was similar to that reported in human pancreatolithiasis, although the severity is less.