家兔左心室流出道电生理特性的研究  

Study of electrophysiological characteristics of rabbit left ventricular outflow tract

作　　者：张晓云[1] 赵兰平[1] 马建伟[1] 焦宏[1] 温晓竞[1] 王雪芳[1] 陈立峰[1] 

机构地区：[1]河北北方学院生理教研室,河北张家口075029

出　　处：《中国现代医学杂志》2008年第3期286-288,292,共4页China Journal of Modern Medicine

基　　金：河北省中医药管理局项目(No.05018)

摘　　要：目的探讨左心室流出道电生理特性及其与心律失常的关系。方法该实验利用常规的玻璃微电极细胞内记录技术,观察了钾离子浓度、低氧及pH等对离体家兔左心室流出道慢反应自律细胞的电生理特性的影响。结果用2.5mmol/LK+灌流,可使最大舒张电位(MDP)、动作电位幅值(APA)、0相最大除极速率(Vmax)明显减小(P<0.05),自发放电频率(RPF)明显加快(P<0.01),而且表现为一过性心律失常。用6.5mmol/LK+灌流后,MDP、APA、Vmax及舒张期除极速率(VDD)均显著减小,RPF明显减慢(P<0.05),在灌流中自发节律不稳定,变异较大。无糖低氧液灌流10min,该自发慢反应电位的VDD及RPF明显变慢(P<0.01),分别用pH5.5和pH8.5的灌流液后,表现为心动过速、过缓等心律失常,而其电位的形态及其他指标无显著变化。结论低氧、K+水平及pH高低均可影响家兔左心室流出道自律性电活动,使其自律性发生改变,笔者认为这可能与临床上起源于心室流出道的心律失常有关,这将为临床诊断和治疗流出道心律失常提供理论依据。[ Objective] To explore the electrophysiological characteristics of the left ventricular outflow tract and its role in arrhythrnia. [Methods]In this experiment conventional intraceilular microelectrode technique was used to record spontaneous slow action potentials; K^＋ concentration, hypoxia and the influenc of pH level on rabbit left ventricular outflow tract pacemaker ceils electrophysiological characteristic were observede. [Results] 2.5 mmol/L K^＋ significantly decreased the maximal diastolic potential （MDP）, amplitude of action potential （APA） and maximal rate of depolarization （Vmax） （P 〈0.05）, while rate of pacemaker firing （RPF） significantly increased as compared with the control （P 〈0.01）. Perfusion with 6.5 mmol/L K^＋ resulted in a significant reduction of the MDP, APA, Vmax, velocity of diastolic depolarization （VDD） and RPF （P 〈0.05）. With the condition of hypoxia and deprived glucose content fluid, after 10 minutes, VDD and RPF obviously slowed down （P 〈0.01）. Respectively using pH 5.5 and pH 8.5 to the perfusate, their spontaneous firing frequency obvious changed, as manifested as arrhythrnia such as tachycardia, bradycardia. But there was no notable changes in formation of spontaneous slow action potentials. [ Conclusion ] The result indicates that the automaticity of rabbit left ventricular outflow tract can be influenced by K^＋ level, hypoxia and pH level, this may be related to arrhythmia originated from ventricular outflow tract in clinic. This will provide a theoretical base for the clinical diagnosis and treatment of outflow tract arrhythmia.

关 键 词：左心室流出道 电生理 心律失常 

分 类 号：R-332[医药卫生] R541.7