Abstract
In order to study the nature of the release of gastrin by insulin, 8 unoperated ulcer patients were submitted to 2 insulin tests. After insulin an increase in serum gastrin concentrations from 117 + 16.1 to 162 + 15.2 pg per ml (53 to 73.6 pmol/1), mean + S. E. M., was found. Hypoglycaemia was prevented by simultaneous glucose infusion during the second test, which showed no increase in serum gastrin concentrations. The role played by the antrum was evaluated in 15 patients treated with resection of the distal part of the stomach, and in 3 patients treated with resection of the upper part of the stomach. After insulin no increase was found in the former, while a definite increase was found in the latter patients. It is suggested that the gastrin response to insulin is caused by hypoglycaemia, and that it is of antral origin.