AsymptomaticH. pylori infection impairs pH inhibition of gastrin and acid secretion during second hour of peptone meal stimulation

Abstract
H. pylori infection is associated with acid-peptic disease, although its role in the pathogenesis is unclear. The purpose of this study was to determine if chronic infection in asymptomatic subject impairs the inhibition of meal-stimulated gastrin and acid secretion that is observed normally at low intragastric pH. Presence of infection was determined by both C-14 urea breath test and serology. Acid secretion was measured under basal conditions and in response to peptone meal stimulation and pentagastrin. Plasma gastrin concentrations were determined by radioimmunoassay under basal conditions and during peptone meal stimulation. Intragastric titration with 1% peptone during the first hour, and 8% peptone during the second hour, was performed at both pH 7.0 and 2.5 on different days to compare the inhibition of gastrin and acid secretion. Compared to noninfected subjects, asymptomatic individuals infected withH. pylori had significantly increased: (1) basal gastrin values (PPP=0.01). During the second hour of peptone-stimulation, subjects infected withH. pylori had significantly decreased inhibition of gastrin (52% vs 95%) (P=0.002) and acid (30% vs 81%) (P=0.01) secretion from pH 7.0 to 2.5. Thus, chronic infection withH. pylori results in impaired inhibition of gastrin and acid secretion at low intragastric pH during the second hour of peptone meal stimulation. These defects may be unrelated to the pathogenesis of acid-peptic disease, since they occur in asymptomatic subjects infected withH. pylori.