Effect of atropine on insulin secretion in healthy subjects

The effect of an anti-cholinergic drug (atropine) on insulin secretion was studied in a double-blind manner by the glucagon C-peptide secretion test in five healthy subjects and controlled with saline only (placebo) in four subjects. Blood C-peptide increased only by 157% in the group given atropine and by 252% in the group given placebo. The blood glucose concentration increased by 25% and 32%, respectively. Thus, it is concluded that the cholinergic system, probably through the vagus nerve, has an insulin secretion stimulating effect. The results also suggest that denervation of the vagus nerve, e.g. in gastric surgery, may partly explain post-prandial hyperglycaemia particularly found in dumping.