吡咯卡因的抗心律失常作用

Antiarrhythmic effects of pyrrocaine hydrochloride

吡咯卡因能对抗乌头碱引起的麻醉大鼠心律失常;能使BaCl_2诱发的大鼠室性心动过速转为正常;能提高豚鼠心脏哇巴因中毒的耐受量;并能降低CaCl_2—ACh诱发的小鼠心室纤颤的发生率和死亡率,其50％有效剂量(ED_(50))与利多卡因相近。本实验测得小鼠ip吡咯卡因和利多卡因的半数致死剂量(LD_(50))分别为140±11mg/kg和143±15mg/kg,但吡咯卡因的急性心脏毒性作用则明显低于利多卡因。

Pyrrocaine hydrochloride ip 20 or 40 mg/kg could significantly counteract arrhythmias induced by aconitine in rats,and iv 4 or 8 mg/kg could also convert BaCl2-induced arrhythmia into sinus rhythm in rats.The drug could increase the tolerant dose of ouabain to produce ventricular extrasystole(VE),ventricular tachycardia(VT),ventricular fibrillation(VF)and cardiac arrest(CA).It decreased the occurrence of VF and the mortality induced by CaCU-ACh in mice,so did lidocaine.The values ofED50 of iv pyrrocaine against VF and CA induced by CaCl2-ACh in mice were 5.1 and 4.2 mg/kg respectively; similarly,those of lidocaine were 4.7 and 4.5 mg/kg respectively.The LD50 of pyrrocaine and lidocaine were 140±11 and 143±15 mg/kg in mice by ip,yet pyrrocaine is less toxic to the heart of mice than lidocaine by iv.