Vagal Control of Glucagon Release in Man

A significant fall in fasting plasmapancreatic-glucagon was produced by injection of atropine. After arginine infusion atropine reduced the normal rise of glucagon by 33% and glucose by 40%. Eleven patients studied during insulin hypoglycaemia after a selective vagotomy showed a peak rise in plasma-glucagon of 173 pg. per ml., which was not significantly different from the glucagon rise in ten preoperative controls (168 pg. per ml.). The glucagon response to insulin hypoglycaemia (81 pg. per ml.) in a matched group of ten patients with truncal vagotomy was significantly less than after selective vagotomy. This evidence of parasympathetic control of the alpha cell accords with morphological and laboratory-animal findings. Maintenance of normal glucagon release after selective vagotomy favours the use of this operation rather than the cruder truncal vagotomy.