The effect of glucagon on the blood levels of gastrin, insulin and glucose in patients with gastric and duodenal ulcers.

The blood serum levels of gastrin and insulin and arterial blood levels of glucose were determined immediately before intravenous injection of 1 mg of glucagon, and 10, 20, 40 and 60 minutes later in 12 gastric ulcer patients, 14 duodenal ulcer patients and 12 controls using the radioimmunological and orthotoluidine methods respectively. Following glucagon administration the gastrin levels dropped in the controls and the gastrin patients, and increased in the duodenal patients by an average of 30%. Insulin levels increased in all three groups, but the increase was statistically significant in the two patients groups. Glucose levels in the blood also increased with no significant differences between the groups. It is suggested that the different effect of glucagon on gastrin levels may be due to gastrin-insulin interaction; the levels of the two hormones in the blood of duodenal patients were higher than in the other two groups studied.