Ammonia produced by Campylobacter pylori neutralizes H + moving through gastric mucus

Abstract

We aimed to show that Campylobacter pylori infection increases the concentration of ammonia in the gastric mucus and alters the movement of H + through the mucus. Mucus from uninfected and C. pylori-infected stomachs was collected at postmortem. Ammonia was measured enzymatically. The ammonia concentration in C. pylori-infected mucus was fourfold greater than in uninfected mucus. H + movement experiments were carried out using an in vitro chamber, in which a layer of mucus separated a 0.1 M HCl solution from distilled H 2O. The change in pH of the distilled H 2O was measured over 30 min. A drop in pH was measured for uninfected mucus. A slight rise in pH was measured for C. pylori-infected mucus. We conclude that C. pylori infection is associated with reduced H + movement through mucus and that this may be due to increased ammonia concentration within mucus.