Gastrin and somatostatin in Helicobacter pylori infected antral mucosa

Helicobacter pylori infection is associated with increased meal stimulated gastrin secretion, but the reason for this is unknown. Sequence specific radioimmunoassays were used to measure the concentration of alpha-amidated gastrin, the total progastrin product, and somatostatin in biopsy specimens of human antral mucosa. The antral concentrations of alpha-amidated gastrin and of total progastrin products were significantly higher in H pylori infected patients than in those not infected by this organism. In contrast, the antral somatostatin concentration was significantly decreased in infected patients. Progastrin processing, determined by gel chromatography, seemed unaffected by H pylori infection. The results suggest that the finding of increased gastrin secretion from the antral G cells in H pylori infected patients may be a result of reduced inhibition of G-cell secretion by somatostatin.