Effect of acute hyperglycemia on basal and cholecystokinin stimulated exocrine pancreatic secretion in humans.

This study was undertaken to investigate the effect of acute hyperglycemia on pancreatico-biliary secretion in healthy subjects. Duodenal outputs of bilirubin, amylase, trypsin and bicarbonate were measured by aspiration using a recovery marker under basal condition for 75 min and during continuous infusion of CCK (0.5 IDU/kg.h for 60 min). Seven healthy subjects participated in two experiments performed in random order during normoglycemia and during acute hyperglycemic clamping at 15 mmol/l. At regular intervals plasma PP levels were determined as an indirect measure of vagal-cholinergic tone. Basal pancreatico-biliary secretion was significantly (p<0.05) reduced during acute hyperglycemia. CCK significantly (p<0.05) increased bilirubin, amylase and trypsin output both during normo- and hyperglycemia. During the initial 30 min of CCK infusion the bilirubin, amylase and trypsin outputs were significantly (p<0.05) inhibited in the hyperglycemic experiment compared to normoglycemia. In the following 30 min of CCK infusion the bilirubin, amylase and trypsin output were not different between hyper- and normoglycemia. Basal and CCK-stimulated plasma PP concentrations were significantly (p<0.05) reduced during hyperglycemia. In summary: 1) basal pancreatico-biliary secretion is significantly reduced during acute hyperglycemia 2) during hyperglycemia CCK-stimulated pancreatico-biliary secretion is also significantly reduced with the pattern of a delayed response 3) hyperglycemia inhibits basal and CCK-stimulated PP secretion suggesting impaired vagal-cholinergic activity during hyperglycemia.