摘要
目的研究八厘麻毒素(Rh)对在体和离体兔心脏电生理参数的影响。方法使用在体兔心脏模型和Langendorff离体兔心脏灌流模型 ,观察并记录分别用Rh12.5μg·kg-1和25μg·kg-1(iv)或用含Rh浓度为0.34μmol·L-1 和0.68μmol·L-1 的K_H灌注液灌注兔心脏时 ,对在体或离体兔心脏电生理参数的影响。结果在Rh12.5μg·kg-1(iv)后20、40、60和80min,心室舒张阈值 (VDT),有效不应期 (ERP)和相对不应期 (RRP)均无显著变化;而Rh25μg·kg-1(iv)在用药后的同样时间内可见ERP和RRP显著延长(P<0.05)。另用含Rh浓度为0.34μmol·L -1的K_H灌注液行Langendorff灌注 ,心房相对不应期(ARRP)和心房有效不应期(AERP)显著延长 (P<0.05~0.01) ;转用含Rh浓度为0.68μmol·L-1 的K_H灌注液行Lan gendorff灌注 ,心房舒张阈值(ADT)、VDT均明显升高 (P<0.05~0.01) ,且ARRP ,AERP ,心室相对不应期(VRRP)和心室有效不应期(VERP)均显著延长 (P<0.05~0.01)。结论Rh能直接作用于心肌 ,升高心房、心室舒张期阈值和延长心房。
Aim To study effects of rhomotoxin (Rh) on electrophysiologic parameters in rabbit heart. Methods The rabbit hearts in vivo were injected with Rh 12.5 μg·kg-1 , 25 μg·kg-1 or saline iv respectively and the isolated rabbit hearts were perfused by Krebs-Henseleit(K-H) perfusion liquid containing Rh 0.34 μmol·L-1 or 0.68 μmol·L-1. The electrophysiologic parameters were observed before and after drug adminitration.Results At 20,40,60 and 80 min after injection of Rh 12.5 μg·kg-1 iv,the VDT,ERP and RRP had no significant changes; but at 20,40,60 and 80 min after injection of Rh 25 μg·kg-1 iv a significant prolongation of ERP and (or) RRP was found (P<0.05). Perfusing isolated heart with Rh 0.34 μmol·L-1 prolonged ARRP and AERP (P<0.05,P<0.01); while perfusing isolated heart with Rh 0.68 μmol·L-1 increased ADT and VDT (P<0.05,P<0.01) and prolonged ARRP, AERP,VRRP and VERP (P<0.05,P<0.01). Conclusion Rh might have an effect of increasing atrial and ventricular diastolic threshold, which prolongates atrial and ventricular refractory period by direct action on rabbits myocardial muscle.
出处
《中国临床药理学与治疗学》
CAS
CSCD
2000年第4期313-316,共4页
Chinese Journal of Clinical Pharmacology and Therapeutics
关键词
八厘麻毒素
心脏电生理学
离体灌注
rhomotoxin(Rh)
rabbit
cardioelectrophysiology
isolated perfused heart