冉乌头碱的镇痛作用及其对麻醉大鼠心电图的影响

Effects of Ranaconitine on Analgesia and ECG in Anesthetized Rats

目的 :探讨冉乌头碱 ( Ranaconitine,RAN)的镇痛作用及其对麻醉大鼠心电图 ( ECG)的影响。方法 :采用小鼠醋酸扭体法观察 RAN的镇痛作用 ;给麻醉大鼠恒速 iv RAN观察 ECG的变化。结果 :皮下注射 ( sc) RAN6mg/ kg后 35～ 4 5min及 4 5～ 55min均可显著抑制小鼠醋酸扭体反应 ,抑制率分别为 67.76%及 69.55%。静脉注射 ( iv)小剂量 ( 0 .62± 0 .2 9) mg/ kg RAN即可引起大鼠心率( HR)加快 ,当剂量增至 ( 2 .33～ 7.90 ) mg/ kg,可分别引起室性早搏 ( VP)、室性心动过速 ( VT)、心室纤颤 ( VF)、心搏停止 ( CA)等心律失常。结论 :RAN具有镇痛作用。小剂量 RAN可引起大鼠心率加快 ,大剂量可引起快速型心律失常。

Cbjectioe:To study the effects of ranaconitine on analgesia and ECG in the anesthetized rats. Method:The analgesic action of RAN was observed by using the acetic acid writhing test.The changes of writhing response and ECG of anesthetised rats were recorded before and after RAN infused intravenously in a constant rate. Results: RAN 6mg/kg sc could significantly inhibit the writhing response induced by acetic acid after 35～45 min and 45～55min administrated in rats The inhibitory rates were 67.76%and 69.55%,respectively.A small dose of RAN(0.62±0.29)mg/kg could markedly increase the heart rate in rats.Up to (2.33～7.90)mg/kg,RAN could caused arrhythmias such as ventricular premature beats(VP), ventricular techycardia(VT),ventricular fibrillation (VF) and cardiac arrest(CA).Conclusion : RAN has analgesic action.A low dose of RAN can increase the heart rate, wherease the high dose of RAN can induce the arrhythmia.