七氟醚后处理对大鼠心肌缺血再灌注时Na+-K+-ATP酶和Ca2+-Mg2+-ATP酶活性的影响

目的 评价七氟醚后处理对大鼠心肌缺血再灌注时Na+-K+-ATP酶和Ca2+-Mg2+-ATP酶活性的影响,探讨其减轻心肌缺血再灌注损伤的机制.方法 健康雄性Wistar大鼠45只,体重250～280 g,随机分为3组(n=15):假手术组(S组)、缺血再灌注组(I/R组)和七氟醚后处理组(Spo组).I/R组和Spo组采用结扎左冠状动脉前降支30 min时进行再灌注的方法制备心肌缺血再灌注模型,S组仅在左冠状动脉前降支下穿线.Spo组再灌注前1 min开始吸入2.5%七氟醚持续5 min.于再灌注2 h时取心肌组织,测定心肌梗死体积、Na+-K+-ATP酶活性和Ca2+-Mg2+-ATP酶活性.结果 与S组比较,I/R组心肌梗死体积扩大,心肌组织Na+-K+-ATP酶和Ca2+-Mg2+-ATP酶的活性降低(P＜0.05);与I/R组比较,Spo组心肌梗死体积缩小,心肌组织Na+-K+-ATP酶和Ca2+-Mg2+-ATP酶的活性升高(P＜0.05).结论七氟醚后处理可提高Na+-K+-ATP酶和Ca2+-Mg2+-ATP酶的活性,从而减轻大鼠心肌缺血再灌注损伤.

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 significantly 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.