Protective effect of recombinant human erythropoietin against acute myocardial infarction in rats

    ZHANG Yuª²Qing, ZHANG Fuª²Min, ZHANG Dingª²Guo, ZHOU Lei, YAO Jing, CHEN Yiª²Jiang, CHANG Zai, GAO Xiang, LI Chuanª²Fu, HA Tuanª²Zhu, MA Wenª²Zhu, CAO Keª²Jiang

    Department of Cardiology, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China, Animal Model Center, Nanjing University, Nanjing 210000,China, Department of Surgery, East Tennessee State University,Johnson City,TN,37614,USA

    ¡¾Abstract¡¿ AIM: To study the protective effects of recombinant human erythropoietin (rHuEPO) on heart function and infarct size in rats with acute myocardial infarction (AMI) and to explore the mechanism of the protective effect. METHODS: Sixteen Wistar rats were divided randomly into 2 groups: AMI group (n=8) and treatment group (n=8). AMI models were made by ligating the left anterior descending coronary artery(LAD). rhEPO was injected in treatment group (3000 IU/ kg, ip) once daily for 3 conseª²cutive days (1 d before, at the start of, and 1 d after surgery) and 2 wk later (14-16 d after surgery). Transthoracic echocardiography was carried out 2 and 21 d after operation respectively. Then the rats were sacrificed. Infarct sizes were measured by TTC stain, vascular density and the expressions of Bclª²2 and Bax examined by immunohistochemical technique. RESULTS: There was no significant difference in baseline LV functions between AMI group and treatment group 2 d after operation. LVEF and LVDs were significantly improved in treatment group than those in AMI group on 21 d after operation. Also,the smaller infracted size [(26.0¡À0.9)% vs (28.1¡À1.5)%, P<0.05], and higher capillary density[(10.4¡À1.5)/scope vs (6.3¡À0.7)/scope, P<0.05] were confirmed in treatment group than those in AMI group on 21 d after operation. An upª²regulation of Bclª²2 A value [(0.116¡À0.005) vs (0.103¡À0.006), P<0.05] and a downª²regulation of Bax A value [ (0.125¡À0.010) vs (0.147¡À0.014), P<0.05 ] were found in treatment group as compared with those of AMI group. CONCLUSION: RHuEPO could improve rats heart function and reduce infarct size after myocardial infarction, which may be related with reducing apoptosis and stimulating angiogenesis. ......