OBJECTIVETo study the effect of Tiaomaiyin injection on the experimental arrhythmia for analyzing its underlying mechanism in the treatment of cardiovascular disease.

METHODExperimental animals anesthetized with 20% urethane (6 mL x kg(-1)) were evenly randomized into control group, positive control group, low-dose and high-dose Tiaomaiyin group. The rate of ventricular fibrillation (VF) chloroform-induced in mice, and the epoch of ventricular extrasystole (VE), ventricular tachycardia (VT),VF and cardiac arrest (CA), actonitine-induced in rats (1.0 microg x mL(-1) x min(-1)), and vabain-induced in guinea pigs (10 microg x mL(-1) x min(-1)), were detected respectively. The result loas converted into cumulative dosage of actonitine or vabain. In ischemia-reperfusion model in rats, the duration of arrhythmia and activity of superoxide dismutase (SOD) and malondialdehyde (MDA) were detected.

RESULTAfter venous injection of Tiaomaiyin, VF in mice was lower significantly (P < 0.01), VE, VT, VF in rats and VF in guinea pigs were lowered considerably (P <0.05). The duration of arrhythmia in ischemia-reperfusion model was reduced considerably (P < 0.05), and the activity of myocardial SOD was raised significantly (P <0.01).

CONCLUSIONTiaomaiyin shows the reduction of experimental arrhythmia and protect effect to ischemia-reperfusion injury of the heart, which indicates that the effect mechanism may have the relationship with inhabition of lipid peroxidation and damnification of the free radical.