Interaction of calcium and magnesium on gastric acid secretion and serum gastrin concentration in man

The effect of magnesium on calcium- and pentagastrin-induced gastric acid secretion and on calcium-induced gastrin secretion were studied in healthy volunteers. Intravenous infusion of calcium gluconate increased serum gastrin concentration as well as gastric volume secretion, acidity, and acid output. Addition of magnesium sulfate to the infusion caused a slight but insignificant increase in serum gastrin concentration, whereas volume secretion, acidity, and acid output were significantly depressed. Intravenous infusion of magnesium sulfate had no effect on gastric acid secretion induced by a submaximal pentagastrin infusion. The results indicate that magnesium antagonizes the activation of gastric acid secretion by calcium without suppressing gastrin release and may suggest that magnesium does not change the sensitivity of the parietal cell to gastrin.