The role of lipid peroxidation on gastric mucosal lesions induced by water-immersion-restraint stress in rats.

This study was designed to determine the effect of water-immersion-restraint stress (WIRS) and pretreatment by reduced glutathione on both the production of gastric mucosal lesions and the content of gastric mucosal phosphatidylcholine hydroperoxide (PCOOH). Sprague-Dawley rats were divided into control and treatment groups (treated with reduced glutathione before stress). After graded durations of WIRS, the macroscopic ulcer index (UI) was measured and the PCOOH content was examined by a chemiluminescence-high performance liquid chromatography assay. The UI in the control group increased significantly in a time-dependent fashion. Elevation of the PCOOH level was observed in combination with the UI for up to 2h of WIRS, but then showed a declining tendency. Pretreatment with reduced glutathione significantly lowered both the UI and the PCOOH level. Lipid peroxidation is probably involved in the pathogenesis of gastric injury induced by WIRS at least in the early phases. However, in the late phases, other mechanisms causing gastric mucosal lesions may also be involved. We therefore believe this study to be the first to accurately and quantitatively assess the degree of lipid peroxidation in the gastric mucosa as a result of stress.