Secretory effects of gastrins on isolated perfused porcine pancreas

The effects of the four main forms of gastrin (component I, gastrin-34, gastrin-17, and gastrin-14) on insulin, glucagon, and exocrine secretion were measured on the isolated perfused porcine pancreas. All gastrins were studied in concentrations ranging from 10(-11) to 10(-8) M. Depending on the glucose concentration in the perfusate, all four gastrins increased insulin or glucagon secretion in a dose-dependent manner in concentrations above 10(-10) M. These concentrations are slightly above the arterial concentrations in normal pig and man, but they correspond to gastrin concentrations measured in patients with achlorhydria and gastrinomas. The exocrine secretion was stimulated by all gastrins in a dose-dependent manner. The lowest concentrations that stimulated flow rate significantly were within the physiologic range, 10(-11) and 10(-10) M. All gastrins induced maximal flow rate at a concentration of 10(-9) M. The sulfated form of gastrin-17 had the greatest efficacy. The results indicate that all gastrins may influence the exocrine secretion under normal conditions and the endocrine secretion in diseases with endogenous hypergastrinemia.