The insulin-pancreatic acinar axis.

Recent studies indicate that insulin directly regulates the acinar pancreas. Morphologic and hemodynamic studies indicate the presence of a portal system that conveys islet blood to acinar cells. Studies both in humans with diabetes mellitus and in animals given beta cell toxins indicate that insulin is necessary for normal acinar cell function. Studies in the perfused rat pancreas indicate that endogenous insulin potentiates zymogen release. Isolated rat and mouse acini have insulin receptors, and in these cells, after binding to its receptors, insulin regulates a number of functions including: sugar transport, protein synthesis, and the number of cholecystokinin receptors. These in vivo and in vitro studies suggest, therefore, that there is an insulin-pancreatic acinar axis that plays a major role in pancreatic function.