HCN4表达变化对兔窦房结缺血再灌注时电生理功能的影响  

Effect of HCN4 Expression on Electrophysiological Function of Rabbit Sinoatrial Node during Ischemia Reperfusion

作　　者：滕林 曹春雨[2] 周飞 杨伟 李松 丁家望 Teng Lin;Cao Chunyu;Zhou Fei;Yang Wei;Li Song;Ding Jiawang(Department of Cardiology,Yichang Central People's Hospital,The First College of Clinical Medical Science&Institute of Cardiovascular Diseases,China Three Gorges University,Yichang 443003,China;In stitute of Molecular Biology,Medical College of China Three Gorges University,Yichang 443002,China)

机构地区：[1]三峡大学第一临床医学院[宜昌市中心人民医院]心血管内科&三峡大学心血管病研究所,湖北宜昌443003 [2]三峡大学医学院,湖北宜昌443002

出　　处：《巴楚医学》2020年第4期18-23,共6页Bachu Medical Journal

基　　金：湖北省自然科学基金项目(No:2015CFB287)。

摘　　要：目的:观察缺血再灌注条件下兔窦房结组织HCN4的表达变化,探讨其对窦房结电生理功能的影响。方法:将成年新西兰兔随机分为对照组、缺血30 min、60 min、120 min组及缺血再灌注60 min、120 min、240 min组,每组10只。采用结扎及放松右冠状动脉起始部制备兔窦房结缺血再灌注模型,各组同步记录体表心电图及心腔内电图,观察AA、AH及HV间期变化及心律失常发生情况,采用RT-PCR和Western blot法检测窦房结组织HCN4 mRNA和蛋白表达。结果:对照组均无心律失常发生,窦房结组织HCN4 mRNA及蛋白水平较高。与对照组相比,缺血可显著降低窦房结组织中HCN4 mRNA及蛋白水平,且随着缺血时间的延长逐渐降低;再灌注后,随着再灌注时间的延长,HCN4 mRNA及蛋白水平逐渐升高。49只兔缺血后心腔内电图出现AA及AH间期延长,且随缺血时间延长,心律失常发生率及死亡率明显增加;再灌注60 min、120 min及240 min后AA及AH间期均有不同程度的缩短。结论:HCN4表达降低可能是急性心肌缺血时窦房结电生理功能障碍的重要原因,而早期再灌注可诱导HCN4表达上调,有利于窦房结功能恢复,并减少心律失常的发生。Objective:To observe the expression of HCN4 in sinoatrial node of rabbits under the condition of ischemia reperfusion,and to explore its effect on electrophysiological function of sinoatrial node.Methods:Adult New Zealand rabbits were randomly divided into the control group,the ischemia groups(IS 30 min,60 min,120 min)and the ischemia reperfusion groups(IR 60 min,120 min,240 min),with 10 rabbits in each group.The model of ischemia reperfusion in the sinoatrial node were established by occluding and loosening the start section of right coronary artery.The electrocardiography and intracardiac electrocardiogram were recorded synchronously to observe the changes in the AA,AH and HV intervals and the occurrence of arrhythmia.The expression of HCN4 in sinoatrial node tissue were detected by RT-PCR and Western blot.Results:All rabbits in the control group had no arrhythmia,and HCN4 mRNA and protein levels were higher in the sinoatrial node.Compared with the control group,HCN4 was gradually decreased in sinoatrial node along with the prolonged ischemia stress.After reperfusion,HCN4 was gradually increased with the prolongation of reperfusion time.There were 49 rabbits performed with obvious prolongation in the AA and AH intervals after ischemia,and the incidence of arrhythmia and mortality increased significantly with the prolongation of ischemic time.The AA and AH intervals were shortened by reperfusion at 60 min,120 min,and 240 min.Conclusion:The decrease of HCN4 may be the main cause of electrophysiological dysfunctionin in sinoatrial node.Early reperfusion could induce HCN4 expression,which is beneficial to function recovery in sinoatrial node,so as to reduce the occurrence of arrhythmia.

关 键 词：心肌缺血再灌注 HCN4 窦房结 心内电生理 心律失常 

分 类 号：R541.4[医药卫生—心血管疾病]