Introduction. The question of the possibility of recovery of postischemic myocardium remains relevant.Aim. The aim of the study was to study the effect of dispersed decellularized allogeneic extracellular matrix (allogeneic biomaterial, DAB) on the developed fibrous degeneration of the myocardium, as well as to reveal the possible mechanisms of cellular regeneration.Materials and methods. The muscular wall of the heart of rats was subjected to cryodestruction. After 45 days, the rats of the main group were intramyocardially injected with a suspension of allogeneic biomaterialinto the area of the affected myocardium, and the rats of the control group were injected with saline.Results and discussions. In the experimental group, there was a regression of the formed fibrous connective tissue, chemoattraction of progenitor cells, their differentiation and integration into the myocardium. The thickness of the muscular part of the wall of the left ventricle was three orders of magnitude higher than in the control group.Conclusion. Analysis of the results of the study indicates that the heart in adult mammals has a powerful regenerative reserve. It is likely that, based on the use of DAB, a protocol can be developed that allows the restoration of the heart muscle even in conditions of already developed fibrous degeneration.

Introduction. It is known that the problem of regeneration of damaged peripheral nerves is one of the leading problems in traumatology and neurosurgery.Aim. Aim of the study is to determine the features of the innervation of facial muscles when using allogeneic biomaterials.Materials and methods. The experiment was performed on Chinchilla rabbits (n = 36). The facial nerve was cut in the animals. In the control group (n = 9), the wound was sewn up, in the 1st experimental group (n = 12), a fragment of their masticatory muscle was sewn together with a neurovascular bundle to the denervated buccal muscle. In the 2^nd experimental group (n = 15), dispersed allogeneic biomaterials "Regeneration stimulator" and "Vasculogenesis stimulator" were injected into the muscle junction in the operation zone. Rabbits were withdrawn from the experiment for 10, 30, 60 and 180 days. Tissue pieces from the surgery area were examined by transmission electron microscopy.Results and discussion. In the control and 1st experimental groups, the experiment ended with scarring of the operating area and contracture of facial muscles. In the 2^nd experimental group, signs of tissue revascularization and axon germination to the buccal muscle with the restoration of individual neuromuscular synapses were revealed.Conclusion. The use of allogeneic biomaterials in operations to restore damaged peripheral nerves accompanying muscles creates conditions not only for the restoration of muscle fibers, but also the vascular bed, as well as nerve elements with neuromuscular connections.