丹参酮ⅡA磺酸钠对家兔快速心房起搏时心房动作电位及有效不应期的影响

Effect of Sodium TashinoneⅡA Sulfonate on Monophasic Action Potential and Effective Refractory Period in rabbit atria in vivo.

研究丹参酮ⅡA磺酸钠(TSN)对家兔短期快速心房起搏时在体心房单相动作电位(AMAP)及心房有效不应期(AERP)的影响,探讨其防治心房颤动的可能机制。家兔24只,随机分为对照组与TSN组各12只。将电极经颈内静脉置入右房记录AMAP,观察基础状态下、给药后0.5h及以600次/分心房快速起搏后0.5,8hAMAP及其频率适应性的变化。结果:与起搏前相比对照组在S1S1200ms刺激时测量的AERP(AERP200)在起搏后0.5h缩短21.2ms,起搏后8h缩短21.6ms(P<0.05),且心房肌的频率适应性丧失。TSN在基础状态下对AMAPA、AMAPD无明显影响,但使AERP200由105.9±3.8ms延长至114.7±7.2ms(P<0.05)。起搏后TSN组维持原有的心房肌频率适应性。结论:快速心房起搏使心房肌的频率适应性丧失而致电重构,TSN能减轻短期快速心房起搏所致电重构。

To determine the effects of Sodium Tashinone Ⅱ A Sulfonate （TSN） on monophasie action potential（MAP） and effective refractory period （ERP） in rabbit atria in vivo, Twentyfour rabbits were equally divided into two groups randomly： Control group and TSN group. Electrode leads were localized in the right atrium through right internal jugular veins. Right atrial monophasic （MAP） was recorded by multiple channel recording. ERP of right atrial （AERP） was assessed by programmed electrical stimulation before pacing and 0.5, 8h after the onset of the pacing. Results ： The AERP200 （ S1S1200 ms） of control group was shortened from 106.4 ± 7.3 ms to 84.8 ±7.6 ms and the rate-dependent of atrium was lost after rapid pacing 8h compared with before pacing （ P 〈 0.05 ）. TSN had no effect on the amplitude of MAP and AMAPD （ atrial MAP duration at 90% repolarization） , while the AERP200 was prolonged from 105.9 ± 3.8 ms to 114.7 ± 7.2ms （P 〈 0.05 ） after TSN administration and the rate-dependent of atrium was maintained after the pacing process. Conclusion： Rapid atrial pacing induce the electrical remodeling of atrium by the lost of atrial rate-dependent, and TSN can reduce the degree of atrial electrical remodeling.