Restoring rats’ endurance ability after forced physical exercise under various methods of allogeneic biomaterial implantation

Abstract

One of the manifestations of skeletal muscle plasticity is its atrophy, as an adaptive response to catabolic stimuli. They can occur during forced exhausting physical activity. Injection of local anesthetics, glucocorticosteroids, etc., is widely used to correct such pathological manifestations. The purpose of the study was to reveal the skeletal muscle morphofunctional characteristics of experimental animals after forced physical activity under conditions of subcutaneous and combined methods of administration of allogeneic biomaterial (BMA). The model of anaerobic physical exercise was forced swimming of male rats with a load of 10% of body weight. After the swimming test, the animals were divided into four groups. In the first (experimental) group (n=10), the BMA suspension was administered only subcutaneously. In the second (experimental) group (n=10), BMA suspension was injected in combination, i.e., into the muscles of the limbs and subcutaneously. In the control groups, saline solution was administered using similar methods. After tissue collection on days 5 and 21, morphological, physiological, and statistical studies were carried out. The use of BMA contributed to an increase in load tolerance, and accelerated restoration of muscle tissue, hypertrophy, and hyperplasia. There was a decrease in inflammation, and restoration of microcirculation and ultrastructure of muscle fibers: contractile elements, energy balance of cells, and proliferative activation of the nuclear apparatus. Implantation of BMA promoted inhibition of fibrosis, reduction in the number of necrotic muscle fibers, and chemoattraction of macrophages. The greatest effectiveness determined was with the combined administration of the biomaterial. BMA has an actoprotective effect.