Abstract:

BACKGROUND: It was uncertain that the migration, differentiation and survival of transplanted bone marrow mesenchymal stem cells (BMSCs) into myocardium after the acute myocardial infarction.

OBJECTIVE: To investigate the migration, differentiation and survival of rabbit transplanted autologous BMSCs in myocardium after the acute myocardial infarction.

METHODS: Rabbit BMSCs were isolated and labeled by DAPI in vitro. Rabbit left anterior descending branch was ligated to establish acute myocardial infarction models. Following successful model establishment, 30 New Zealand rabbits were assigned to BMSC and control groups (n = 15). In the BMSC group, autologous BMSCs were infused into the surrounding sites of the infracted region by 4 points 1 hour following coronary artery ligation. In the control group, the same region was injected with an equal volume of saline. Injection volume was 30 μL in each point. Five animals from each group were sacrificed 10 minutes, 3 days and 4 weeks following transplantation. The heart was obtained to undergo frozen sections. The distribution of DAPI-labeled BMSCs was observed using fluorescence microscope. Immunofluorescence method was used to examine the troponin Ⅰ and α-actin.

RESULTS AND CONCLUSION: DAPI-labeled BMSCs with blue nuclei were distributed extensively in the myocardium of the cell transplantation group, ovoid in shape and arranged in parallel with the cardiac muscle fibers. Troponin Ⅰ and α-actin were positive immunofluorescently in the cytoplasm of the labeled BMSCs. Results indicated that transplanted BMSCs in the ischemic myocardium could differentiate into myocardial cells under stimulation of local microenvironment.