Effect of ixeris sonchifolia pretreatment on expression of hypoxia-inducible factor-1α following myo-cardial injury induced by exhausting exercise in rats / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the effect of ixeris sonchifolia pretreatment on the expression of hypoxia-inducible factor-1α(HIF-1α)following myocardial injury induced by exhausting exercise in rats.Methods Fifty-six healthy clean-grade male Wistar rats,weighing 200-220 g,were divided into 3 groups using a random number table method: control group(group C,n＝8),exhausting exercise group(group E,n＝24)and ixeris sonchifolia pretreatment group(group IS,n＝24).In E and IS groups,the model of myocardial injury was established by exhausting swimming.In group IS,the rats were subjected to exhaust-ing swimming after intraperitoneal ixeris sonehifolia 20 ml/kg.In E and IS groups,blood samples were taken from the inferior vena cava at 0,6 and 24 h after exhaustion(T1-3)for determination of serum cardiac tro-ponin I(cTnI)concentrations by enzyme-linked immunosorbent assay.The animals were sacrificed after an-esthesia,and myocardial specimens were obtained for determination of the cell apoptosis index(by TUNEL)and expression of HIF-1α,Bax and Bcl-2(by immunohistochemistry),and Bax/Bcl-2 ratio was calculated.The area of myocardial injury was observed using HBFP assay.Results Compared with group C,the area of myocardial injury,concentration of serum cTnl,Bax/Bcl-2 ratio and apoptosis index were significantly in-creased,and the expression of HIF-1α in myocardial tissues was up-regulated at each time point in E and IS groups(P＜0.05).Compared with group E,the area of myocardial injury,concentration of serum cTnl,Bax/Bcl-2 ratio and apoptosis index were significantly decreased,and the expression of HIF-1α in myocardi-al tissues was down-regulated at each time point in group IS(P＜0.05).Conclusion The mechanism by which ixeris sonchifolia pretreatment mitigates myocardial injury induced by exhausting exercise is related to inhibiting up-regulated expression of HIF-1α in myocardial tissues and reducing cell apoptosis in rats.