Effects of tempol on p38MAPK activation of gastric mucosa ulceration in rat after water-immersion restraint stress / 解放军医学杂志

ABSTRACT

Objective To investigate the temporal activation of p38MAPK signaling transduction cascade,and the relationship between the activation and reactive oxygen species(ROS)in a well-defined experimental model of water-immersion restraint(WIR)stress-induced gastric mucosa ulceration.Methods Male Sprague-Dawley rats were randomly divided into control group,WIR group and tempol treated group.Animals were restrained and immersed in water bath to induce gastric mucosal lesions,with or without pretreatment with the free radical scavenger,tempol,and the WIR group animals were killed at different time points after WIR stress.Tempol treated animals underwent the same protocol followed 30min or 360min of stress,then the gastric mucosa was harvested,and the activity of gastric mucosal p38 was analyzed by Western blot.Malondialdehyde(MDA)activity and pro-inflammatory cytokine expression were detected.Results A rapid activation of p38MAPK in gastric mucosa occurred as early as 15 min after stress,and this activation was maximal after 90min of stress and still persisted until 360min after stress.Pretreatment with tempol prevented stress-induced p38MAPK activation at 30 min and 360min time points(0.77?0.24 and 0.58?0.12,respectively)compared with that in model groups(1.22?0.16 and 1.73?0.09,respectively,P