脂联素对大鼠心肌缺血-再灌注损伤时心律失常的影响

目的：观察脂联素对大鼠心肌缺血再灌注损伤时心律失常的影响并探讨其可能机制。方法：32只8周龄雄性大鼠被随机分为假手术组、缺血一再灌注（IR）组、地尔硫卓组和脂联素（APN）组，每组8只。①假手术组：只穿线，旷置90min；②IR组：先阻断血流30min，再灌注60min；③地尔硫卓组和APN组：先阻断血流30min，于再灌注开始时，从鼠尾静脉分别注射地尔硫卓（3．5μg／g·min）、APN（60ng／g·min）．再灌注60min。以Medlab生物信号采集处理系统连续监测各组心电图的变化。各模型组于再灌注60min后处死大鼠。测定血清、心肌组织一氧化氮（NO）的含量。结果：（1）与假手术组比较，IR组再灌注60min时段里．8只大鼠均出现再灌注心律失常．再灌注过程中ST段抬高的幅度显著增高（P〈0．001），心肌组织、血清中NO含量均明显降低（P〈0．001）；（2）与IR组比较．APN组再灌注60min时段里，没有出现再灌注心律失常，再灌注过程中ST段抬高幅度显著下降（P〈0．001），心肌组织、血清中NO含量均明显升高（P〈0．001），且优于地尔硫卓组（P〈0．001）。结论：脂联素对缺血一再灌注损伤造成的心律失常有一定的保护作用．其机制可能与脂联素增加心肌组织、血清中NO含量有关。

Effect of adiponectin on arrhythmia induced from myocardial ischemia-reperfusion injury in rats

Objective： To investigate the protective effect of adiponectin on arrhythmia induced from myocardial ischemia-reperfusion injury and the potential mechanism in rats. Methods： Thirty-two mate rats aged 8 weeks were randomly divided into groups of sham operation （sham）, myocardial ischemia-reperfusion （IR）, diltiazem treatment （diltiazem） or adiponectin administration （APN）, with 8 rats for each group. Sham group were suffered with sham operation. IR group were undergone anterior descending coronary （ADC） ischemia for 30 min and 60 min ADC reperfusion. Both diltiazem and APN group were given ADC ischemia for 30min. The caudal intravenous injection of dilti- azem at dose of 3.5 μg/g · min and APN at dose of 60 ng/g ·min was respectively performed within 2 min and followed by another reperfusion for 60min in diltiazem group and APN group. The ECG was monitored by Medlab before and after reperfusion. The animals in four groups described above were killed after 60 rain reperfusion for determining the nitric oxide （NO） in serum and myocardial tissues. Results： （1） Eight rats in IR group all showedemerged reperfusion arrhythmia following ischemia-reperiusion, while ST segments were significantly elevating during reperfusion （P〈0. 001）, NO level in serum and myocardial tissue were also significantly decreased as compared with the sham group （P〈0. 001） ; （2） In comparison with IR group, any reperfusion arrhythmia did not present for APN group following ischemia-reperfusion, ST segments were significantly descending to considerable extent （P〈0. 001） during reperfusion, NO concentration in the serum and the cardiac muscle was remarkably increased （P〈0. 001）. The pharmacologic actions of APN were superior to that of diltiazem （P〈0. 001）. Conclusion.. Adiponectin can protect the stability of heart electric activity from ischemia-reperfusion injury in rats, its mechanism may be involved in the increased concentration of NO level in serum and myocardial tissue.