Modified short detergent-enzymatic decellularization method was used in adult male Lewis rat hearts. For recellularization mesenchymal stem cells (MSCs) were injected retrograde via the aorta ascendens into the scaffold of the heart. To evaluate morphology, viability, metabolic activity of cells seeded on the heart scaffold we used MTT-test, life/dead staining and IVIS. Histological data obtained after whole organ recellularization showed cells attached to the inner surface of the heart chambers and coronary vessels inside the scaffold. MTT-test showed cells metabolic activity and proved potential nontoxicity of the obtained scaffold. Monitoring of viable and dead cells in the reseeded scaffold indicated that the majority of the cells remained viable during prolonged cultivation on the scaffold; about 10% of the cells were dead. In vivo bioluminescence imaging also showed the presence of viable cells, defined in the whole organ along the coronary vessels. The result after recellularization proved that obtained scaffold of decellularized rat heart is not toxic to MSCs and promotes cell attachment.