Effect of a specific serine protease inhibitor on the rat pancreas. II. Influence of camostate on the endocrine pancreas.

Chronic oral administration of camostate, a specific serine protease inhibitor, is known to induce pancreas hypertrophy in rats. A possible influence of the protease inhibitor on the endocrine rat pancreas was studied using isolated perfused pancreas and islet incubations. The presence of camostate had no direct effect on the glucose-induced insulin release in vitro in concentrations from 1 microM to 1 mM, but enhanced the basal insulin release from islets cultured over 24 h in media containing the protease inhibitor (100 microM). Administration of camostate over 14 days to rats induced a remarkable hypertrophy of the pancreas without influencing plasma insulin or gastric inhibitory polypeptide levels and insulin concentration of the pancreas. Glucose-stimulated insulin release from the perfused pancreas was not increased despite significantly higher total insulin content. It is concluded that camostate exerts no direct effect on the glucose-stimulated insulin release and that chronic administration of the compound induces pancreas hypertrophy in vivo without influencing insulin release.