Antral and fundic D-cell numbers in Helicobacter pylori infection

Helicobacter pylori infection is associated with an exaggeration of gastrin release following meals or bombesin stimulation attributed to a defect of somatostatin secretion of antral D-cells. Nevertheless, these modifications of gastric physiology do not explain the increase of gastric acid secretion which is only observed in duodenal ulcer patients. The inhibitory effect of somatostatin secretion of fundic D-cells on parietal cells is well known. The aim of our prospective study was to compare the number of fundic D-cells and likewise the number of antral G-cells and D-cells between patients with duodenal ulcer and healthy subjects with and without H. pylori infection.

The numbers of D-cells and G-cells were compared between 19 infected patients with duodenal ulcer and 20 healthy subjects, 10 with and 10 without H. pylori infection. Fundic mucosal biopsy specimens were examined using immunohistochemical techniques specific for the presence of somatostatin, antral mucosal biopsy specimens for the presence of gastrin and somatostatin.

The number of G-cells was significantly lower (P = 0.0012) in duodenal ulcer patients by comparison with infected subjects and controls. The number of antral D-cells was significantly less (P < 0.0001) in duodenal ulcer patients (mean of 10 random fields = 0.45 +/- 0.04) than in either asymptomatic infected patients (0.65 +/- 0.07) or uninfected controls (0.88 +/- 0.10). The number of fundic D-cells was significantly lower (P < 0.0001) in duodenal ulcer patients (mean = 0.20 +/- 0.03) than in either asymptomatic infected subjects (0.29 +/- 0.05) or controls (0.73 +/- 0.09); here the difference between the two groups of infected subjects was not significant. Multivariate analysis showed that the presence of H. pylori infection of the fundic mucosa did not influence the number of fundic D-cells.

Changes in the number of fundic and antral D-cells induced by H. pylori infection did not explain abnormalities of gastric acid secretion usually observed in duodenal ulcer patients; it is suggested that pre-existing abnormalities in the regulation of parietal cell or increase of parietal cell mass are involved.