Protective effect of Daidzein on myocardial ischemia injury in rats

    YE Heª²Yang, HU Zhiª²Ping, ZHOU Li,HUANG Zhiª²Hua, ZENG Jing

    1Department of Pharmacology, 2Department of Physiology, Gannan Medical College, Ganzhou 341000, China

    ¡¾Abstract¡¿ AIM: To observe the protective effect of Daidzein on rats whose branch of left anterior descending coronary arteries were ligated. METHODS: Rats¬ð ischemia injury model was established by ligating the branch of left anterior descending coronary artery for a durative course of 120 min. Thirtyª²two male rats were randomly divided into 4 groups: sham operation group, model group, highª²dose (5.0 mg/kg) Daidzein group and lowª²dose (2.5 mg/kg) Daidzein group. The two Daidzein groups were injected with Daidzein of 1 mL/100 g through sublingual vein 10 min before ischemia injury and saline was given in sham operation group and model group. The lead¢ò ECG was recorded before myocardial ischemia injury, 15 min after ischemia and 30, 60, 90 and 120 min after injection with Daidzein. The ¡Æª²ST of lead ¢ò ECG at each moment mentioned above was analyzed and the Jª²point and Tª²ware of ECG in acute myocardial ischemia model were observed to evaluate the protective effect of Daidzein. The activity of creatine phosphokinase (CK) and lactate dehydrogenase (LDH) in serum, the contents of malondialdehyde (MDA) and superoxide dismutase (SOD) in myocardial tissue were observed to evaluate the protective effect of Daidzein. The myocardial infarct size was measured by TTC staining of cardiac muscle cells in another 24 rats (divided into 3 groups: model group, Daidzein 5.0 mg/kg group, Daidzein 2.5 mg/kg group) with myocardial ischemia injury induced by the same methods. RESULTS: Compared with those in model group, the area of acute myocardial infarction declined, the value of ¡Æª²ST reduced and the maximum values of Jª²point and Tª²ware of ECG declined in the 2 Daidzein groups. The activity of LDH and CK in the 2 Daidzein groups was lower than that in the model group. The content of SOD was significantly higher and MDA was markedly lower in the Daidzein groups than those in the model group. All the changes mentioned above showed some doseª²dependent effect. CONCLUSION: Daidzein has obvious protective effect on myocardium against ischemia injury caused by ligating the branch of left anterior descending coronary artery. ......