Rosmarinic Acid On The Protective Effect And Mechanism Of Coronary Artery Ligation In Rats With Myocardial Ischemia

Objective Through the influence of Rosmarinic Acid(RA) on the model of myocardial ischemia by descending anterior branch of the left coronary artery ligation in rats,the protective effects and possible mechanisms of Rosmarinic Acid on myocardial ischemia were investigated in this study.Methods Acute myocardial ischemia model were made by ligating the descending anterior branch of the left coronary artery in healthy male Wistar rats and divided randomly into six groups:sham group,model group,isosorbide dinitrate group,three Rosmarinic acid(RA) groups with low dosage,middle dosage and high dosage.We observed the change of ST-T segment of ECG in different period,the level of CK-MB,GOT,LDH,cTnT in serum,SOD and MDA in cell,the infarction area in ligated heart and the pathological change of myocardium.At the same time,the expression of bcl-2 and bax was studied by immunohistochemistry.Results Compared with the sham group,ST-T segment in ECG in the model group elevated obviously in different period,the level of CK-MB,GOT,LDH,cTnT and MDA increased,value of SOD decreased. The infarction area and the pathological changes were found obviously in the ligated heart.In the RA groups,compared with the model group,the maximal values of ST-T segment elevation in ECG decreased clearly,the level of CK-MB,GOT,LDH,cTnT decreased,the value of MDA reduced and the value of SOD increased.The infarction area in ligated hearts were reduced and the myocardial necrosis were relieved.The immunohistochemisty results displayed that the expression of bax and bcl-2 in model group increased compared with sham group,especially the bax.The expression of bax and bcl-2 in All RA groups also increased compared with sham group,but lower bax than model group.Conclusion The RA can prevent rat myocardium from acute ischemic injury.One of the mechanisms may be related to increasing the enzyme activity of anti-xoidation to remove free radicals,the other is to reduce myocardial apoptosis by increasing the expression of bcl-2 and decreasing the expression of bax.