炙甘草汤对快速起搏心房电重构的影响

Effect of Zhigancao Decoction on Atrial Electrical Remodeling Induced by Rapid Atrial Pacing in Rabbits

目的观察炙甘草汤对快速心房起搏所致心房电重构的影响,探讨其防治房颤的可能机制。方法将实验家兔随机分为对照组(假手术组)、起搏组和药物组(起搏+炙甘草汤),每组各6只。家兔开胸后,将刺激电极置于家兔右心耳部位,记录电极置于家兔左心房,采用单相动作电位(MAP)记录技术和心脏程序刺激法,分别测定以600次/min心房快速起搏8 h后各组兔心房肌AERP200、AERP150和AERP/APD90比值等电生理指标。结果与对照组相比,起搏组AERP、AERP/APD90比值均明显缩短、AERP频率适应性降低、房颤诱发率增加且房颤平均持续时间延长(P<0.05)。药物组AERP、AERP/APD90比值,AERP频率适应性,房颤诱发率和房颤平均持续时间与对照组差别不大(P>0.05)。结论炙甘草汤可有效抑制快速心房起搏所致兔心房电重构,可能是其有效防治房颤发生和维持的作用机制。

Objective： To investigate the effects of Zhigancao Decoction（ZD） on atrial electrical remodeling in- duced by rapid atrial pacing in rabbits and to explore prevention and therapy mechanism of ZD on atrial fibrilla- tion（AF）. Methods： 18 rabbits were randomly divided into control group （n=6）,pacing group （n=6） and drug group （n=6）. After medial thoracotomy was performed, stimulating electrode was sutured to right atrial appendage, recording electrode was sutured to left atrium,rabbits were paced at 600 beats per minute for 8 hours in pacing group and drug group. After pacing 8 hours,monophasic action potential （MAP） recording and heart program electric stimulation techniques were used to measure the effects of ZD on electrophysiology parameters. Results： The effective refractory period （AERP） was significantly shortened,the rate adaptability of AERP was markedly decreased,and ERP/MAPg0 ratio were shorter in pacing group compared with control group. The inducibility and duration of induced AF were increased in pacing group. The difference between drug group and control group had no statistical significance. Conclusion： ZD can inhibit atrial electrical remodeling induced by rapid atrial pacing, which may be preventive and therapeutic mechanism of ZD on AF.