Calcium-antagonistic effects on glucose response to glucagon in patients with non insulin-dependent diabetes mellitus and in normoglycemic subjects.

The current study was performed in order to investigate whether verapamil would affect the glucose response to glucagon differently in patients with non insulin-dependent diabetes mellitus (NIDDM) compared with age-matched normoglycemic controls. For that purpose glucagon was injected intravenously on a background infusion of verapamil, and for comparison also on a background infusion of saline in these two groups. Verapamil was found to blunt the glucose response to glucagon in the patients with NIDDM, whereas it augmented the glucose response to glucagon in the controls. This discrepancy could not be explained on the basis of verapamil-induced changes in the release of insulin, since verapamil did not effect the serum responses to glucagon. However, it could reflect the differences in hepatic handling of glucose, which has been shown to prevail in patients with NIDDM compared with healthy controls.