Acute and chronic effects of bile acids on the epithelial acid-base transporters in barrett's esophagus

Introduction: Barrett's esophagus (BE) is a premalignant condition where normal squamous epithelium is replaced by metaplastic columnar epithelium. While combined acidic and biliary reflux is thought to have an important role in the mucosal injury, the acid-base transporters of the esophageal epithelial cells (EEC) may be key factors of the defense. Our previous studies indicated the presence of Na+/H+ exchanger (NHE-1) and Na+/HCO3- cotransporter (NBC) and a Cl- dependent HCO3- secretory mechanism: Cl-/HCO3- exchanger (Slc26a6); however their reaction to reflux of gastric acid and bile has not been established…