慢性激活天门冬氨酸受体对心室复极变异性储备和心律失常的影响  

Effects of chronic N-methyl-d-aspartate receptor activation on ventricular repolarization variability, reserves and arrhythmias

作　　者：石少波[1,2] 刘韬[1,2] 梁锦军[1,2] 唐艳红[1,2] 杨波[1,2] 黄从新[1,2] 

机构地区：[1]武汉大学人民医院心内科,430060 [2]武汉大学心血管病研究所,430060

出　　处：《中华心律失常学杂志》2014年第6期464-468,共5页Chinese Journal of Cardiac Arrhythmias

基　　金：国家重点基础研究发展计划（973项目：2012CB518604）;国家自然科学基金（81200139）;湖北省自然科学警拿璎旱（2013cFA11）;中央高校基本科研业务专项基金（201430202020）

摘　　要：目的 研究慢性激活天门冬氨酸（N-methyl-d-aspartate,NMDA）受体对心室复极变异性和储备的影响,探讨其诱发室性心律失常的可能机制.方法 36只成年雄性Wistar大鼠分为：对照组（CTL组）、NMDA受体激动剂组（N组）和NMDA受体激动剂＋抑制剂组（N＋M组）.在Langerdorff灌流下,行不同频率的S1S1和短阵快速（Burst）刺激左心室前壁和后壁;记录单向动作电位复极到90％的时限（MAPD90）的动态变化,计算短时限变异（STV）、电交替阈值和室性心律失常的诱发率.结果 与CTL组相比,以不同周长刺激时,N组MAPD90和STV的动态变化幅度显著增大;诱发电交替的起搏周长显著增高[（111.67±2.97）ms对（88.33±2.41）ms,P＜0.01];刺激完成前的STV明显增大[（12.18±0.81）ms对（3.61±0.29）ms,P＜0.01];N组的室性心律失常诱发率和持续性室性心律失常比例均高于CTL组：S1S1模式：83.33％对25.00％,P=0.02和75.00％对8.33％,P＜0.01;Burst模式：100％对25％P＜0.01和83.33％对25.00％,P=0.02.N＋M组的上述变化与CTL组相近,差异无统计学意义（P＞0.05）.结论 慢性激活NMDA受体明显增加室性心律失常的易感性,可能与心脏复极变异性增大和复极储备降低有关.Objective The purpose of this study was to investigate the effects of chronic N-methyl-d-aspartate receptors （NMDAR）activation on ventricular repolarization variability,reserves,and to explore the possible mechanisms of NMDAR induced ventricular arrhythmia.Methods A total 36 Wistar rats were randomly divided into control group（CTL group）,NMDA group（N group） and NMDA＋MK-801 group（N＋M group）.In Langerdroff-perfusedrat hearts,the S1 S1 and Burst stimulations were performed to construct the dynamic changes of monophasic action potential（MAPD）,then calculating the short-term variability（STV）,the threshold of alternans and inducibility of ventricular arrhythmias.Results Compared with the CTL group,the dynamic changes of MAPD90 and STV showed significantly increased in the N group at dynamic stimulus;the threshold of alternant was significantly increased（111.67±2.97）ms vs.（88.33±2.41）ms,P〈0.01.The STV before completion of stimulation significantly increased in the N group （12.18 ± 0.81） ms vs.（3.61 ± 0.29） ms,P〈0.01 ; the incidence of ventricular arrhythmias and the proportion of sustained ventricular arrhythmias were higher in the N group than that in the CTL group：S1 S1 model：83.33% vs.25.00%,P=0.02 and 75.00% vs.8.33%,P〈0.01 ;burst model：83.33% vs.25.00%,P =0.02.The above electrophysiology alterations were not statistically significance in the N＋M group compared with that in CTL group.Conclusion Chronic activation of NMDA receptors significantly increased the susceptibility to ventricular arrhythmias.This may be related with increased variability of cardiac repolarization and decreased repolarization reserve.

关 键 词：天门冬氨酸受体 复极变异性 复极储备 室性心律失常 

分 类 号：R541.7[医药卫生—心血管疾病]