Serum gastrin in duodenal ulcer. I. Basal levels and effect of food and atropine.

Fasting serum gastrin has been measured by radioimmunoassay in 72 patients with duodenal ulcer and compared with that in normals, patients with gastric ulcer, and with the Zollinger-Ellison syndrome. The mean (+/- SEM) gastrin levels were 15.7 +/- 1.5 pg/ml in the duodenal ulcer group, 32.1 +/- 4.3 pg/ml in normals, 118 +/- 18.1 pg/ml in gastric ulcer, and between 450 and 2,000 pg/ml in the Zollinger-Ellison syndrome. There were no difficulties in distinguishing simple ulcer from the Zollinger-Ellison syndrome as the presence of hyperchlorhydria in combination with hypergastrinaemia led to a confident diagnosis of the latter disease.The effect of protein, glucose, and cream feeding with and without atropine was also assessed in a group of these patients with duodenal ulcer. As in normals, there was no stimulation of gastrin release by either atropine alone, distilled water, glucose, or cream. However, protein alone produced a greater rise in serum gastrin levels compared with that in normals and prior atropinization augmented this response greatly in duodenal ulcer. This indicates an increased amount of releasable gastrin in the latter disease, the release of which, under basal conditions, is suppressed by the high acidity in the antrum.