TWA在急性心肌缺血心律失常中的作用机制及其预防和治疗

发布时间：2018-12-25 08:15

【摘要】：目的：TWA可以预测心肌梗死心律失常的发生，但其机制没有统一的认识。本实验通过给予雷诺嗪、兰尼碱、维拉帕米，进一步探讨急性心肌缺血时TWA的机制，并为临床预防和治疗急性心肌缺血心律失常提供依据。方法：50只日本大耳白兔随机分为正常组、缺血组、雷诺嗪组、兰尼碱组、维拉帕米组，并制备左心室楔形心肌块。雷诺嗪为晚钠通道抑制剂，兰尼碱为RyR2受体阻滞剂，维拉帕米为钙通道阻滞剂。采用玻璃微电极，同步记录心肌内、外膜跨膜动作电位、跨壁的心电图及其心肌收缩力。观察雷诺嗪、兰尼碱及维拉帕米对TWA及心律失常的影响。正常组给予持续台氏液灌注，缺血组在给予灌注台氏液稳定1小时后，停止灌注台氏液20分钟，然后诱发TWA的发生，雷诺嗪组、兰尼碱组及维拉帕米组在灌注台氏液稳定1小时后分别给予含有雷诺嗪、兰尼碱、维拉帕米的台氏液预灌注，然后停止灌注含有雷诺嗪、兰尼碱、维拉帕米的台氏液20分钟，分别诱发TWA的发生。兔的左心室楔形心肌块在基础状态下给予1000ms步长持续刺激，停止灌注台氏液或含有上述药物的台氏液20分钟后给予200ms的步长刺激诱发TWA并观察心律失常的发生。结果：与正常组比较，缺血组TWA及心律失常的发生明显增加。正常组无TWA及心律失常的发生；与正常组比较，缺血组中10/10的产生TWA，5/10的产生心律失常。与缺血组相比，维拉帕米组中TWA及心律失常的发生明显减低，在维拉帕米组中无TWA及心律失常的发生。与缺血组相比，雷诺嗪组中TWA及心律失常的发生明显增加，在雷诺嗪组中10/10的发生TWA，10/10的发生心律失常。兰尼碱组与缺血组相比，TWA及心律失常的发生无明显差异，，在兰尼碱组中8/10发生TWA，4/10的发生心律失常。结论：钙通道阻滞剂维拉帕米可以抑制TWA及心律失常的发生，这说明钙离子紊乱是急性心肌缺血TWA发生的重要机制。
[Abstract]:Objective: TWA can predict arrhythmias in myocardial infarction, but the mechanism is not uniform. In this study, the mechanism of TWA in acute myocardial ischemia was further investigated by the administration of ranolazine, lannitine and verapamil, and the basis for clinical prevention and treatment of acute myocardial ischemia arrhythmias was provided. Methods: fifty Japanese white rabbits were randomly divided into three groups: normal group, ischemia group, ranosin group, ranidine group and verapamil group. Ranolazine was used as a late sodium channel inhibitor, lannitine as a RyR2 receptor blocker and verapamil as a calcium channel blocker. The transmembrane action potential, transmural electrocardiogram (ECG) and contractility of myocardium were recorded simultaneously by glass microelectrode. The effects of ranolazine, raniline and verapamil on TWA and arrhythmia were observed. The normal group was perfused with continuous Tetranyl solution, the ischemia group stopped the infusion of Tetranyl solution for 20 minutes after the infusion of Tetranyl solution was stabilized for 1 hour, then the occurrence of TWA was induced in Renolazine group. After one hour of steady infusion of Tyrlozin solution, the Ranifen group and the verapamil group were preperfused respectively with Renolazine, Rannitine, verapamil, and then stopped infusing the Tetrandrine solution containing Renolazine, Lannidine and verapamil for 20 minutes, respectively. TWA was induced respectively. The rabbit left ventricular wedge block was stimulated with 1000ms step in basal state, and the TWA was induced by the step stimulation of 200ms 20 minutes after stopping the infusion of Tetranyl solution or Tetrachlor solution containing the above mentioned drugs, and the occurrence of arrhythmia was observed. Results: compared with the normal group, the incidence of TWA and arrhythmia increased significantly in ischemic group. There was no TWA and arrhythmia in normal group, and 10 / 10 of TWA,5/10 was produced in ischemic group. The incidence of TWA and arrhythmia in verapamil group was significantly lower than that in ischemic group, but no occurrence of TWA and arrhythmia was found in verapamil group. Compared with ischemic group, the incidence of TWA and arrhythmia increased significantly in Renolazine group, and TWA,10/10 arrhythmias occurred in 10 / 10% of Renolazine group. There was no significant difference in the occurrence of TWA and arrhythmias between the Lannidine group and the ischemic group. The incidence of TWA,4/10 arrhythmias occurred in 8 / 10 of the Lanni base group. Conclusion: verapamil, a calcium channel blocker, can inhibit the occurrence of TWA and arrhythmias, which suggests that calcium disturbance is an important mechanism of acute myocardial ischemia TWA.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：R542.22

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