RESUMO
The content of colony-forming cells in myocardial cell culture from the perinecrotic zone of rat heart was evaluated on day 40 after cryodestruction. The mean cellularity after cryodestruction was 12-fold lower than in intact animals. Intramyocardial transplantation of bone marrow cells (mononuclears, mesenchymal stem cells, and mesenchymal stem cells treated with 5-azacitidine) into the perinecrotic zone increased the content of colony-forming cells. After transplantation of mesenchymal stem cells and mesenchymal stem cells treated with 5-azacitidine, the number of colonies reached 33 +/- 7 and 11 +/- 3, the mean cellularity being 2975 +/- 80 and 1105 +/- 42 cells/cm2, respectively. Hence, intramyocardial transplantation of mesenchymal stem cells created an appreciable pool of colony-forming cells in the myocardial perinecrotic zone. Treatment with 5-azacitidine reduced survival of mesenchymal stem cells after intramyocardial transplantation.
