EFFECTS OF HELICOBACTER-PYLORI ON HISTAMINE AND CARBACHOL-STIMULATED ACID-SECRETION BY HUMAN PARIETAL-CELLS

Helicobacter pylori (H pylori) infection is associated with hypo, norm al, and hypersecretory disorders of the gastric mucosa. Pathophysiolog ical pathways by which H pylori interacts with acid secretion are stil l. unclear. The effects of H pylori on (C-14) aminopyrine uptake by hu man parietal cells were examined as an indirect assay for acid secreti on, Isolated oxyntic glands were stimulated with submaximal concentrat ions of histamine or carbachol and incubated with sonicates of differe nt H pylori strains. Omeprazole and sonicates of Campylobacter jejuni served as positive and negative controls, respectively. Two of four H pylori strains reduced hydrochloric acid sequestration within the pari etal cells significantly and in a dose dependent manner in up to 80%. Interaction with acid secretion may therefore constitute a factor cont ributing to a distinct pathogenicity of H pylori strains.