七氟烷缺血后处理对离体大鼠心肌细胞的保护作用

目的观察七氟烷缺血后处理对离体大鼠心肌细胞凋亡的影响。方法20只♂Wistar大鼠随机分为缺血对照组(A组)和七氟烷缺血后处理组(B组),每组10例。两组离体鼠心均用Langendorff离体心脏灌注模型,以改良Kreb-Henseleit液灌流平衡20min后,停灌40min,再灌注60min。B组在复灌时以平衡有1.0Mac的七氟烷灌注液灌注15min。以Powerlab Chart 5软件动态监测左室展压(LVDP)、左室压力变化最大速率(±dp/dtmax),心率(HR)。计量平衡20min、复灌15min和复灌60min的冠状动脉灌注流量(CF)。以2,3,5-氯三苯四唑染色(TTC)染色心肌切片,并以Image J 1.37软件计算心肌梗死面积。TUNEL法检测染色凋亡细胞,尼康高倍光学显微镜(Nikon Eclipse,E400,日本)视野拍照并存档,以Leica Qwin Plus V3软件分析,计算凋亡指数(AI)。结果和A组比,B组复灌后的LVDP、±dp/dtmax、CF和HR均明显升高(P<0.05);B组复灌后心梗面积明显减小且AI明显降低(P<0.05)。和基础值比,复灌15min以及复灌60min的LVDP、±dp/dtmax、CF和HR均显著降低(P<0.05)。结论七氟烷缺血后处理抑制离体大鼠心肌的细胞凋亡,提示对缺血再灌注(I/R)心肌具有心肌保护作用。

Cardioprotection of sevoflurane postconditioning on isolated rat hearts

Aim To observe the protective effect of sevoflurane on reperfused myocardium of isolated rat hearts.Methods 20 male Wistar rat hearts were isolated,linked to a Langendorff apparatus and randomly divided into 2 groups:control group(group A),and sevoflurane postconditioning group(group B).Isolated perfused rat hearts were exposed to 40 min of ischemia followed by 60 min of reperfusion with modified Kreb-Henseleit(K-H) buffer.Anesthetic postconditioning was induced by 15 min of 1.0 Mac sevoflurane administered at the onset of reperfusion.The left ventricular developed pressure(LVDP),and the maximum rate of increase or decrease of left ventricular pressure(±dp/dtmax) were recorded at the end of the stabilization period,15 min and 60 min after reperfusion.Infarct size was determined by 2,3,5-triphenyltetrazolium chloride staining.Myocardial TUNEL staining was used in situ cell death detection kit(POD,Roche,Germany).The percentage of TUNEL positive nuclei to all nuclei counted was used as apoptotic index(AI).Results Compared with those of group A,the data of hemodynamics of LVDP,±dp/dtmax,CF and HR of group B were significantly higher but the infarct size and AI of group B were much lower during reperfusion period than those in group A(P<0.05).Compared with baseline value,the data of LVDP,±dp/dtmax,CF and HR decreased significantly in both groups(P<0.05).Conclusion Anesthetic postconditioning by sevoflurane effectively protected against reperfusion damage by preventing myocardial apoptosis in rat hearts.