Abstract
The infusion of 900 μmoles of calcium chloride into the pancreaticoduodenal artery for 10 min resulted in a significant fall in the secretion of pancreatic glucagon. When 90 μmoles of calcium chloride were injected into the pancreatic artery for 10 sec, the plasma insulin in the pancreatic vein rose transiently and the plasma glucagon decreased significantly. The injection of either calcium gluconate or lactate brought about the same results as produced by the calcium chloride injection with respect to the insulin and glucagon levels in the pancreatic vein. The suppressive effect of calcium on pancreatic glucagon was prominent when calcium was infused into the pancreatic artery during arginine infusion. By the infusion of organic salts, arginine-induced hyperglucagonemia was blunted. The present experiment demonstrates the direct effect of calcium upon pancreatic glucagon secretion.
