1.   The factors that regulate gastrin secretion are complex.

2.   Increased gastrin mediated acid secretion seems to be the key factor in the pathophysiology of duodenal ulceration and explains the role of H pylori infection in the disorder.

3.   To overcome this problem we have measured gastrin mediated acid secretion after the intravenous infusion of gastrin releasing peptide.

4.   Gastrin mediated acid secretion did not fall in the one patient whose infection was not eradicated.

5.   It is this dual defect that causes their considerable sixfold increase in gastrin mediated acid secretion.

6.   The effect of H pylori on gastrin mediated acid secretion provides a scientific explanation for the role of the infection in the pathogenesis of duodenal ulceration.