摘要
目的探讨晚钠电流(INa-L)在心力衰竭模型兔室性心律失常中的作用。方法 40只新西兰大耳白兔随机分为假手术组、心衰组、海葵毒素(ATX-Ⅱ)组和雷诺嗪组,每组10只。心衰组、ATX-Ⅱ和雷诺嗪组通过缩窄腹主动脉制备兔心力衰竭模型,假手术组开腹但不缩窄腹主动脉。心力衰竭模型建造成功后,制备兔左室楔形心肌块灌注模型,采用浮置玻璃微电极法同步记录左室楔形心肌块心内膜、心外膜心肌细胞跨膜动作电位和跨室壁心电图。假手术组和心衰组灌注正常蒂罗德液,ATX-Ⅱ组在灌注正常蒂罗德液的基础上加灌10nmol/L的ATX-Ⅱ,雷诺嗪组在灌注正常蒂罗德液的基础上加灌20μmol/L的雷诺嗪。同时记录各组室性心律失常的诱发率。结果心衰组兔室性心律失常的发生率显著高于假手术组(60%vs.0%);INa-L增强剂ATX-Ⅱ进一步增加了心力衰竭兔室性心律失常的发生率(100%vs.60%);INa-L阻断剂雷诺嗪可显著减少心衰兔室性心律失常的发生率(10%vs.60%)。结论 INa-L在兔心力衰竭室性心律失常的发生中起着重要作用,阻断INa-L可减少心衰时心律失常的发生。
Objective To investigate the role of late sodium current（INs-L） in ventricular arrhythmia（VA） in rabbits with heart failure. Methods A total of 40 rabbits were randomly allocated to sham-operated（sham）,heart failure（HF）,ATX-Ⅱ and ranolazine groups with 10 in each group. Heart failure models were established in HF,ATX-Ⅱ and ranolazine groups by abdom- inal aortic constriction,while rabbits in the sham group underwent a sham-operation in which the abdominal aorta was only ex- posed but not constricted. Thereafter,the left ventricular wedge preparation was made, and the transmural ECG and the action potentials from both endocardium and epicardium were simultaneously recorded in the whole process in all experiments. The ani- mals in the sham and HF groups were perfused with nomal Tyrode＇s solution,and those in the ATX-Ⅱ and ranolazine groups with normal Tyrode＇s solution containing ATX-Ⅱ（10 nmol/L） or ranolazine（20 μmol/L）. The incidence of VA was obtained under program electrical stimulation. Results The incidence of VA in the HF group was significantly higher than in the sham group（60%vs. 0%） ,and it was significantly increased in the ATX- Ⅱ group when compared with HF group（100% vs. 60%）. Fewer VAs occurred in the ranolazine group than in the HF group（10% vs. 60%）. Conclusion INa-L plays a very important role in the occurrence of VA in rabbits with heart failure,and blocking INa-L can evidently reduce the occurrence of VA.
出处
《华中科技大学学报（医学版）》
CAS
CSCD
北大核心
2013年第2期152-155,共4页
Acta Medicinae Universitatis Scientiae et Technologiae Huazhong
基金
国家自然科学基金资助项目(No.30971180
No.30973601
No.81001571)
武汉市科技攻关计划项目(No.201260523171-2)
