Piperazine Experimental Arrhythmias And Its Cardioprotective Effect

Objective: To study the effect and mechanism of Piperazine onantiarrhythmia and heart protection Method: Observe the antiarrhythmiaactivity of Piperazine through the ventricular fibrillation induced by chloroformin mices, the arrhythmia induced by adrenalin in rabbits, arrhythmia induced bybarium chloride, by aconitine and by myocardial ischemia-reperfusion(I-R) inrats. The heart protection and mechanism of Piperazine were determinedthrough measuring the injured size by dying the ventricles of I-R rat in NBTsolution, determining the contents of LDH, MDA in serum of rats, measuringthe heart rates of anaesthetized rats and using the model of myocardial hypoxiainduced by obstruction of the trachea in mices. Results: Pipreazine hadremarkably effect on preventing ventricular fibrillation induced by chloroformin mices, the incidences of VF were attenuated (P<0.01). It was also effective inshortening the duration time of arrhythmia induced by adrenalin in rabbits(P<0.01). The arrhythmia induced by barium chloride in rats was antagonizedby Piperazine, the incidences of arrhythmia were attenuated (P<0.01).Pipreazine could prevent the arrhythmia induced by aconitine in rats, the dose ofaconitine in VP, VT, VF, CA was increased (P<0.05). Furthermore it couldprevent arrhythmia induced by I-R in rats, the number of VP, the duration timeof VT and the incidences of VF were largely decreased. It could also reduce theinjured size of the ventricles of I-R rat, decrease the heart rates of anaesthetizedrats and cut down the amount of MDA and LDH in serum (P<0.01). MeanwhilePiperazine could prevent myocardial hypoxia induced by obstruction of thetrachea in mices, time of cardio acoenesthesia was prolonged(P<0.01).Conclusion: Piperazine has obvious protective effect on experimentalarrhythmia and can reduce the injured size of I-R rats. It can also decrease theheart rates of anaesthetized rats and attenuate the contents of LDH, MDA inserum. The effect may be related to its inhibition of the activity of sympatheticnerve and of Na⁺ or Ca²⁺ influx or its enhancement of K⁺ efflux, which willaffect the electric-physiological property of membrane. The myocardialprotection of Piperazine may be associated with the reduction of myocardiallipid peroxidation and the decrease of heart rates.