Effect of sevoflurane postconditioning on activities of Na＋-K＋-ATPase and Ca2＋ -Mg2＋ -ATPase during myocardial ischemia-reperfusion in rats

Objective To investigate the effect of sevoflurane postconditioning on the activities of Na＋ -K＋ -ATPase and Ca2＋ -Mg2＋ -ATPase during myocardial ischemia-reperfusion （I/R） in rats and the possible mechanism. Methods Forty-five healthy male Wistar rats weighing 250-280 g were randomly divided into 3 groups （ n = 15 each）： sham operation group （group S）, I/R group and sevoflurane postconditioning group （group Spo）. Myocardial I/R was induced by occlusion of anterior descending branch of left coronary artery for 30 min followed by 120 min of reperfusion. In group S the anterior descending branch was only exposed but not ligated. Group Spo received 5 min inhlation of 2.5% sevoflurane 1 min before reperfusion. The myocardial tissues were taken at 2 h of reperfusion for determination of infarct size and activities of Na＋ -K＋ -ATPase and Ca2 ＊ -Mg2 ＊ -ATPase. Results The infarct size was significantly larger and the activities of Na＋ -K＋ -ATPase and Ca2＋ -Mg2＋ -ATPase were signifi cantly lower in group I/R than in group S （ P 〈 0.05）. The infarct size was significantly smaller and the activities of Na＋ -K＋ -ATPase and Ca2＋ -Mg2＋ -ATPase were significantly higher in group Spo than in group I/R （P 〈 0.05 ）. Conclusion Sevoflurane postconditioning can reduce myocardial I/R injury through increasing the activities of Na＋ -K＋ -ATPase and Ca2＋ -Mg2＋ -ATPase. Key words: Sodium-potassium-exchanging ATPase;  Ca（2 ＋ ） Mg（2 ＋ ）-ATPase;  Myocardial reperfu sion injury;  Sevoflurane postconditioning