Effect Of Sevoflurane Preconditioning Combined With Postconditioning On Myocardial Ischemia/Reperfusion Injury In Rats

ObjectiveBy detecting TNF-α and caspase-3content of the myocardial tissue in SD rats by sevoflurane inhalation to investigate the effect of sevoflurane preconditioning combined with postconditioning on TNF-α and caspase-3expression of sevoflurane preconditioning combined with postconditioning on myocardial ischemia/reperfusion injury in rats.Methods40male SD rats of clean grade weighing230～270g were randomly divided into5groups (n=8each):Sham operation group (group S), Ischemia and reperfusion group (group I/R), sevoflurane preconditioning group (group S-Pre), sevoflurane postconditioning group (group S-Post), sevoflurane preconditioning combined with postconditioning group (group S-Pre+S-Post). Established the model of rats’ myocardial ischemia reperfusion, ligation the left anterior descending coronary artery in30min,120min after reperfusion, group S only threading, not ligation. In group S-Pre, before ischemia30min, inhale2.5%sevoflurane15min and wash15min; In group S-Post, before reperfusion10min, inhale2.5%sevoflurane15min; In group S-Pre+S-Post, before ischemia30min, inhale2.5%sevoflurane15min and wash15min and before reperfusion10min, inhale2.5%of sevoflurane15min. Record HR and MAP before ischemia30min, after ischemia30min and120min after reperfusion, at the same time calculate the RPP (SP×HR). After being reperfused for120min, under light-microscopy pathological changes of every group myocardial were observed, myocardial TNF-α and caspase-3expression were detected by immunohistochemistry.Results①Compared with the group S, after reperfusion120min, MAP and RPP decreased (P<0.05)in the other four groups; Compared with the I/R group, HR, MAP and RPP were no significant difference (P>0.05) in group S-Pre, group S-Post and group S-Pre+S-Post. Compared with the group S-Pre and group S-Post, HR, MAPand RPP were no significant difference (P>0.05) in group S-Pre+S-Post.②Compared with the group S, after reperfusion120min, TNF-a and caspase-3expression increased (P<0.05)in the other four groups; Compared with the I/R group, TNF-a and caspase-3expression were significantly lower in group S-Pre, group S-Post and group S-Pre+S-Post (P<0.05). Compared with the group S-Pre and group S-Post, TNF-a and caspase-3expression were significantly lower in group S-Pre+S-Post (P<0.05).③Under the light microscope, S-Pre group, S-Post group and S-Pre+S-Post group pathology of myocardial damage reduced comparing with that in I/R group. And compared with S-Pre group and S-Post group, the degree of myocardial damage in S-Pre+S-Post group relieved.Conclusion①Myocardial ischemia-reperfusion injury can cause myocardial tissue TNF-a and caspase-3increased expression.②Sevoflurane can protect myocardial ischemia-reperfusion injury in rats by inhibiting expressions of TNF-a and caspase-3, this may be the play myocardial protection mechanism.③Compared with only sevoflurane preconditioning or postconditioning, the two methods in combination can reduce TNF-a and caspase-3expression, and further reduce myocardial ischemia/reperfusion injury.