ABSTRACT
Objective:To clarify the role of Heat shock proteins (HSPs) on the cardiac function during acute myocardial infarction (AMI) after bone marrow cell implantation (BMT), we examined the expression of HSP32 and HSP70 in a rat model of myocardial infarction. Methods: Myocardial infarction model was induced in the inbred Lewis rats by left anterior descending artery ligation,and 5?10 6 of bone marrow mononuclear cells (BM MNCs) were injected into an ischemic zone. On days 1, 3, 7 and 14 post infarct, the differentiations of transplanted cells and the expressions of HSP32 and HSP70 were determined by immunofluorescence or RT-PCR. The cardiac function was evaluated by echocardiography. Results: Immunofluorescence microscopy of hearts from BMT group revealed that expressions of HSP32 and HSP70 were promoted within cardiomyocytes in the infarction zone and the peri infarct zone,and expressed within some transplanted bone marrow cells as well. RT-PCR also showed the mRNA expression levels of HSP32 and HSP70 in BMT group were significantly higher than those of the control group, peaked on day 3 post infarct (5.0 fold and 2.9 fold, respectively, P