ABSTRACT
In our study, BrdU-labeled marrow stem cells (MSCs) were directly (group 1), by the coronary artery (group 2), or by the ear vein (group 3) transplanted into myocardium to observe their distribution and differentiation in acute myocardial infarction (AMI) rabbit models. BrdU-positive cells, and BrdU and α-sarcomeric actin double positive cells were visible in the infarcted zones and its peripheral region. Cell processes between BrdU-positive cells and between BrdU-positive cells and host cardiomyocytes linked together. Transverse striation and sarcomere were seen. In above zones, new blood capillaries composed of Brdu-positive endothelial cells were present. Density of new blood capillaries was greater in group 1-3 than in control group (p < 0.05) and was the greatest in group 2. Hear function in group 1-3 was improved and was the best in group 2 (p < 0.05). In group 2 and 3, BrdU-positive cells were found in the lungs, liver, and kidneys. In group 3, BrdU-positive cells were greater in the lungs than in the liver and kidneys. We can see that MSCs transplanted by the three ways all can induce the regeneration of cardiomyocytes and blood capillaries. The order from good to poor effectiveness is group 2, group 1, and group 3.