Apigenin On Myocardial Ischemia - Reperfusion Injury In Rats

Objective:To investigate the protective effects of Apigenin in myocardium of rats with ischemia-reperfusion(I-R) injury and explore the possible mechanism of the cardio-protective action.Methods:Wistar rats were randomly divided into seven groups with 7 rats in each:Sham-operated group(Sham),Ischemia-reperfusion group(I-R),Solution group(Sol),Verapamil group(Ver),low,middle and high dose Apigenin(1mg/kg,2mg/kg,4mg/kg) groups(Api1,Api2,Api4).The myocardial Ischemia-reperfusion injury model was established through occluding the left anterior descending branch of coronary artery for 30min and removing the ligation later to reperfuse for 2 hours.Sham-operated group had their left anterior descending branch of coronary artery threaded but not ligated.Other groups were injected with physiological saline,Polyethylene Glyeol-400,Verapamil and low,middle and high dose Apigenin in turn through the femoral vein 10 min before the onset of ischemia.After 2 hours' reperfusion,the hearts were removed quickly,fixed by 10%paraformaldehyde and embedded by paraffin,then were made into 4μm microtome sections.Part of the sections were stained by HBPF to observe the degrees of the ischemia and anoxia in myocardium,the others were stained by immunohistochemistry to examine the expression of NF-κB,TNF-α,ICAM-1 in myocardium.We probed into the protective effects of Apigenin in myocardium of rats with Ischemia-reperfusion(I-R) injury and explored its possible action mechanism.Results:(1)HBPF stain:cardiac muscle fibers were stained with yellow in Sham-operated group, while most were with red in Ischemia-reperfusion group and Solution group.Many red cardiac muscle fibers presented a cooking stove form distribution in the low,middle dose Apigenin groups,and individual red myocardium presented spotty distribution in high dose Apigenin group and Verapamil group.(2)Compared with Ischemia-reperfusion group,three Apigenin groups could significantly reduce the expression of NF-κB,TNF-α,ICAM-1 in Ischemia-reperfusion myocardium of rat in a dose-dependent manner(P＜0.01),and there was significant difference between the three Apigenin groups and Ischemia-reperfusion group.Conclusion:(1) Apigenin can evidently lighten the degrees of the ischemia and anoxia in myocardium of rats with ischemia/reperfusion injury,and has the obviously protective function to the myocardium of Ischemia-reperfusion injury.(2) The mechanism that Apigenin is against myocardial Ischemia-reperfusion injury is involved in decreasing the expression of NF-κB,TNF-α,ICAM-1 in myocardium.