Investigations on changes of serum magnesium concentration after glucagon application in healthy humans

The effect of intravenous application of 1 mg glucagon on serum magnesium concentration, potassium, immunoreactive insulin (IRI), and blood glucose in healthy subjects has been studied. A significant decrease of the serum magnesium concentration was observed beginning 5 min after glucagon injection. There is a tendency of a slight but not statistically significant decrease of potassium level at 60 min. The beginning of the decrease of magnesium level was associated with the maximum of IRI-peak. In contrast to the discussed hypothesis that hyperglycemia and hyperinsulinemia cause a shift for magnesium and potassium from the extracellular into the intracellular space we could demonstrate that hyperglycemia is not a necessary condition for the decreasing effect of glucagon on serum magnesium level.