槐花对家兔体外心房肌的作用

目的 :观察槐花对家兔体外心房肌生理特性的影响 ,并探讨其作用机制。方法 :运用体外心脏实验法 ,摘取家兔心房肌 ,观察测定给药前后体外心房肌的收缩力、心率、功能性不应期、静息后加强及正性阶梯效应的变化。结果 :槐花煎液能显著降低心肌收缩力、减慢心率 ,阿托品可抑制槐花的负性心率作用 ,但不能抑制其负性肌力作用 ;槐花煎液可显著减弱家兔体外左心房肌的正性阶梯作用 ,并显著延长功能性不应期 ,但不影响静息后加强效应。结论 :槐花对心肌具有负性肌力和负性频率作用 ,其作用机制与其抑制胞外 Ca2 +跨膜内流有关。

Effects of flos sophorae on isolated rabbit atria

Aim:To study the effects of flos sophorae on physiological characteristics and action mechanism in isolated rabbit atria Methods: The isolated rabbit atria were adopted Before and after giving decocted flos sophorae solution(DFSS),verapamil,heart rate,contractile force of atria,functional refractory period(FRP),post rest contraction and staircase were measured Results: DFSS obviously decreased the contractile force and heart rate of isolated right atrium of rabbit,and its negative chronotropic action can be blocked by atropine DFSS remarkably prolonged the FRP,decreased the positive staircase phenomenon of left atrium of rabbit DFSS had no effect on the post rest potentiation of myocardial contractility in left atrium Conclusion:Flos sophorae possessed negative inotropic and chronotropic actions on isolated atria of rabbit,the mechanism by which the flos sophorae induce the negative inotropic and chronotropic effects may be related to the inhibition of transmembrane flux of calcium