关附甲素对麻醉兔心脏传导和收缩的影响

Effects of Cuan-fu Base A on Cardiac Conductivity and Myocardial Contractility in Anesthetized Rabbits

关附甲素25mg/kg静脉推注延长麻醉兔窦房结恢复时间、窦房传导时间和心房有效不应期,延长P-R间期和希氏束电图的A-H、H-V间期,并降低左室收缩压、dp/dt max和Vpm。以普鲁卡因胺25mg/kg作对照,它们的作用相似,但在用药后15分钟内以关附甲素作用较明显。表明关附甲素对心脏自律性和传导性的抑制有利于防治快速性和折返引起的心律失常。

In this study, 34 rabbits were divided into 3 groups. The Cuan-fu base A 25 mg/kg ⅳ signifantly prolonged the CSNRT, SACT, AERP in the first group of 12 anesthetized rabbits, significantly prolonged the A-H, H-V period of His bundle electrogram in the second group of 11 rabbits, and decreased LVSP, dp/dtmax, Vpm in the third group of 11 rabbits. Similar effects in a control group using procainamide 25mg/kg ⅳ were observed except that in the first 1-15min after medication the effects of Guan-fu base A were stronger. The results of present experiment demonstrated that the inhibitory effects of Guan-fu base A on heart automaticity and conductivity may be the pharmacological basis of its anti-arrhythmic effects. These effects are beneficial to hold up tachyarrhythmia and re—entry. Its negative inotropic action may be a side action. Care should be taken in using the drug for those who suffer from sinus node dysfuntion, conduction disturbance and left ventricular dysfunction.