Helicobacter pylori inhibits the secretory activity of gastric parietal cells in patients with chronic gastritis: An ultrastructural study

Background: Previous in vitro studies suggested that Helicobacter pylori may inhibit the acid secretion of gastric parietal cells. The aim of this study was to investigate ultrastructurally the influence of H. pylori infection on the gastric parietal cell function in vivo. Methods: This study comprised 28 patients with chronic gastritis. Biopsy specimens were taken from the gastric body in all cases and examined by electron microscopy. Gastric parietal cells were counted in each ultrathin section and classified into secretory and non-secretory types. The pH of the gastric juice was also measured in all patients. Results: The number of parietal cells in the secretory phase was significantly lower in H. pylori-infected (n = 16) patients than in those (n = 12) without H. pylori infection. The intragastric pH was significantly higher in patients with H. pylori-associated gastritis than in those without H. pylori infection. Parietal cells in secretory phase tended to decrease in proportion to the activity of the gastric mucosal inflammation. Conclusions: The results of this investigation suggest that H. pylori-associated gastritis is related to a decreased secretory activity of the gastric parietal cells.