Glutathione andglutathione S-transferases inBarrett's epithelium

Summary Glutathione content, enzyme activity and isoenzyme composition of glutathione S-transferases were assayed in normal and Barrett's esophageal epithelium of ten patients with Barrett's esophagus. Inaddition, gastric and duodenal specimens from the same patients were also investigated.Glutathione content, glutathione S-transferase enzyme activity as well as glutathione S-transferase pi content were all significantly lower in Barrett's epithelium as compared to normal esophageal mucosa. In contrast,glutathione S-transferase class alpha enzymes are markedlyexpressed in Barrett's epithelium, whereas only low amounts are present in normal esophageal epithelium. Glutathione and glutathione S-transferase compositionin Barrett's epithelium show striking similarities with gastric epithelium, whereas duodenal epithelium isprovided with considerable higher amounts of glutathione and glutathione S-transferases, except for levels of glutathione S-transferase class pi, which