Effect of glucagon infusion on plasma magnesium, glucose, and insulin in bull calves

Two Holstein bull calves each were infused intravenously with 1 mg glucagon in .9% sodium chloride, and two were given saline alone; 1 wk later treatments were reversed. Glucagon increased concentrations of insulin and glucose but decreased potassium in blood plasma and moderately increased urinary magnesium and calcium losses. When only saline was used, there was no effect. A hypothesis relating elevated glucagon to grass tetany is proposed.