Background/aims : Alterations of gastric mucin have been postulated as important pathogenic properties of Helicobacter pylori. In this study, we investigated gastric mucin synthesis in H. pylori-infected gastric mucosa by measuring UDP-galactosyltransferase (UDP-Gal-T) activity, a key enzyme for the synthesis of mucin, and the amount of intracellular mucin in the gastric mucosa.
Methods : Gastric biopsy specimens were obtained from thirty-seven patients(20 H. pylori-positive and 17 H. pylori-negative). UDP-Gal-T activity of the biopsy specimens was measured by an assay aystem we had developed, using a peanut agglutinin lectin. The amount of intracellular mucin in the gastric epithrlial cells was analyzed by measuring the cells' periodic acid-Schiff-alcian blue staining-positive subtances.
Results : UDP-Gal-T activites in the antral mucosa of H. Pylori-positive patients were significantly lower than that of H. pylori-negative patients (p<0.05). The amount of intracelluar mucin in the antral epithelial cells of H. pylori-positive patients was significantly lower than that of H. pyolori-negative patients (p<0.01).
Conclusions : H. pylori infection decreases gastric mucin synthesis by the inhibition of UDP-Gal-T activity. This effect may impair the gastric mucosal barrier and contribute to the mucosal injury induced by H. pylori infection.