Experimental study on protective effects of Urapidil on heart muscle ischemia and reperfusion injury in rats / 中国医师杂志

ABSTRACT

Objective To observe the effects of ?1-receptor antagonist Urapidil on the size of myocardial infarction and arrhythmias in the rats model of ischemia-reperfusion(I/R) and to investigate the dose-effect relationship.Methods One hundred Sprague-Dawley rats were randomly divided into 5 groups with 20 rats each sham operation group,I/R group and therapy group(Urapidil 3 mg/kg,6 mg/kg,12 mg/kg).Ten rats in each group were subjected to 10 min of left anterior descending branch of coronary artery ligation and 15 min of reperfusion and Urapidil was injected 5 min before the ligation.The ventricular arrhythmias of ischemia-reperfusion was observed.The other 10 rats in each group were subjected to 30 min of left anterior descending branch of coronary artery ligation and 40 min of reperfusion.Urapidil was injected 15 min before blood circulation was regained.The content of serumal enzyme and the myocardial infarct size were observed.Results Compared with the I/R group,the incidence of ventricular arrhythmias was lower and the duration of arrhythmias was significantly shorten,as well as the incidence of ventricular fibrillation(VF) and mortality was lower with the treatment of Urapidil in the therapy group.The result showed that the effect of Urapidil was of dose dependent.The release of serumal enzyme resulted from ischemia-reperfusion injury was reduced in therapy group than that of I/R group and there was no significant difference among the different dosages in the therapy group.The myocardial infarct size was significantly lower in the therapy group than that of I/R group and there was no obvious difference among the different dosages in the therapy group.Conclusion There is protective effect on the ischemia-reperfusion injury in rats with the treatment of urapidil with the dosage of 3,6 and 12 mg/kg respectively.