Potentiation of glibenclamide-induced insulin release by calcium infusion

The effect of calcium on glibenclamide-induced insulin release was studied in 14 diabetic patients. Two mg glibenclamide was given intravenously and calcium, blood glucose and IRI were determined in venous blood samples at predetermined intervals. The test was repeated 3-4 days later with the patients simultaneously receiving a calcium infusion into a contralateral vein. The decrease in blood glucose and the rise in IRI level were both significantly greater in the combined glibenclamide-calcium test. It is concluded that calcium may temporarily improve carbohydrate tolerance in diabetic patients by potentiating the glibenclamide-stimulated insulin secretion.