Modifications in Pancreatic Enzyme Proportions following Secretory Stimulations

The short-term influence of repeated secretory stimulations of the pancreas on pancreatic enzyme content was studied in the rat. The animals received 10 successive injections of either cholecystokinin-pancreozymin (CCK-PZ), secretin, CCK-PZ plus secretin, caerulein or pilocarpine. The pancreatic enzyme content was determined the next morning. CCK-PZ, with or without secretin, caerulein and pilocarpine had a similar influence increasing the chymotrypsinogen concentration in the pancreas twofold, while lipase and amylase concentrations increased by only 50 and 25%, respectively. Fasted and fed animals responded similarly. Secretin, a mostly ductal secretagogue, was without influence on the pancreatic enzyme composition. Thus, the mere stimulation of pancreatic protein secretion seems to result in a rapid change in enzyme composition in the pancreas.