Newly synthesized amylase, lipase and serine proteases are transported at different rates in rat pancreas.

The rates of intracellular transport of newly synthesized amylase, lipase, trypsinogen and chymotrypsinogen were compared in the anaesthesized rat pancreas by measuring their rates of secretion while keeping their relative rates of synthesis in a steady state. It is concluded that pancreatic proteins are not transported all at the same rate through the acinar cell. Among the four enzymes studied, proteolytic enzymes are transported faster than lipase, and amylase is the slowest. The relative rates of transport of these enzymes are not altered by secretory stimulation, since similar results were obtained in the basal state and under constant caerulein infusion (300 ng/kg/h).