七氟醚预处理通过改善心肌Cx43侧面化减轻缺血／再灌注性心律失常

目的探讨缝隙连接蛋白43（Cx43）侧面化在七氟醚预处理减轻离体大鼠心脏心肌缺血／再灌注性心律失常方面的作用。方法雄性Wistar大鼠24只，随机分为3组（n=8）：对照组（c组）、缺血／再灌注组（IR组）、3％七氟醚预处理组（SP组）。采用Langendorff灌注装置进行离体心脏灌注：C组持续灌注90min；IR组平衡30min，缺血30min，再灌注30min；SP组平衡10min，3％七氟醚预处理15min，洗脱5min，缺血30min，再灌注30min。记录各组的心电图，并于再灌注结束后取左心室游离壁通过免疫荧光观察Cx43的侧面化情况。结果与IR组相比，sP组的期前收缩次数明显减少（P〈0．05），室性心动过速和心室纤颤的时程明显缩短（P〈0．05），心室纤颤发生率降低（P〈0．05），心律失常评分降低（P〈0．05）。Cx43的侧面化情况sP组明显优于IR组（P〈0．05）。结论七氟醚能有效减轻缺血／再灌注性心律失常的发生，其机制可能与改善Cx43的侧面化程度有关。

Sevoflurane preconditioning attenuates ischemia/reperfusion- induced arrhythmias by suppressing the lateralization of connexin 43

Objective To explore the role that lateralized connexin 43 takes in attenuating ischemia./reperfusion - induced arrhythmias in isolated rat hearts by sevoflurane preconditioning. Methods Twenty -four male Wistar rats were randomly divided into a control group （Group C ） , an ischemia/reperfusion group （Group IR） , and 3% sevoflurane pre- conditioning group （ Group SP） （ n = 8 ）. Then, the Langendoff apparatus was adopted to infuse fluids into isolated hearts. Group C was perfused with K - H solution for 90 min. Group IR was first perfused with K - H solution for 30 rain, followed by 30 min of ischemia before 30 min of reperfusion. Group SP was first persfused with K - H solution for 10 rain, then received t5 min preconditioning by 3% sevoflurane and 5 min of wash - out, followed by 30 min of ische- mia before 30 min of reperfusion. The ECG data of each group were recorded. The level of lateralized Cx43 was measured by immunofluorescence. Results Compared with the IR group, the SP group presented less frequent premature contrac- tion and ventricular fibrillation, shorter courses of ventricular taehyeardia and fibrillation, lower scores of arrhythmias, and superior levels of lateralized Cx43 （ each P 〈 0.05 ）. Conclusion Sevoflurane preconditioning can effectively atten- uate ischemia/reperfusion - induced arrhythmias, which my attribute to an increased amount of lateralized Cx43.