Резюмелазерное воздействие может стимулировать пролиферацию клеток и восстановление различных тканей после повреждения. Оста ется неизученным возрастной аспект влияния лазера на регенерацию мышц, в частности, реакция миосателлитоцитов и зрелых миоцитов. Целью исследования являлось изучение влияния лазерного излучения на площадь ядер и количество миосателлитоцитов, а также площадь ядер миоцитов на модели посттравматической регенерации скелетной мышцы у животных разных возрастных групп. Материал и методы. Эксперимент проведен на 32 беспородных крысах, разделенных на 2 группы: юных (3 месяца) и старых (30 месяцев). Сформированные хирургические повреждения икроножной мышцы на левой конечности были опытными, где осуществлялось лазерное воздействие (1060 нм, мощность -2,0 Вт, непрерывный режим, 60 с, однократно), повреждения на правой конечности служили динамическим контролем. Выведение животных из эксперимента проводили на сроках 7 и 14 суток. Образцы тканей фиксировали в формалине, готовили гистологические срезы, окрашивали гематоксилин-эозином и пикрофуксином по Ван-Гизон, проводили морфометрический анализ цифрового изображения объектов. Результаты. Установлено, что после лазерного воздействия на мышцу достоверно увеличивается площадь ядер и количество миосателлитов по сравнению с контрольной группой вне зависимости от возраста животного. Реакция на лазер со стороны ядер миоцитов проявляется в обеих возрастных группах, но достоверно выше у юных животных. Заключение. полученные результаты подтверждают возможности лазерного излучения активировать регенерацию мышц независимо от возраста животного. Ключевые слова: лазер, механическое повреждение, скелетная мышечная ткань, миосателлиты, миоциты. Для цитирования: Галлямутдинов Р.В., Астахова л.В., Головнева е.С., Серышева О.Ю. Влияние лазерного инфракрасного излучения на некоторые морфофункциональные показатели регенерирующей скелетной мышцы в возрастном аспекте // лазерная медицина. -2020. -Т. 24. -№ 2-3. -С. 90-94.

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Laser exposure stimulates cell proliferation and tissue repair. Branched-chain amino acids (BCAA) are widely used in sports medicine as a stimulator of anabolic processes. However, there is no evidence of the effect of combined laser and BCAA application on skeletal muscle morphometric characteristics during exercise in the training process.Purpose: to study the effect of infrared laser exposure in combination with amino acid at myosatellitocytes and skeletal muscle myocytes during swimming training.Material and methods. The experiment was conducted on 30 Wistar rats: Group 1 – intact, Group 2 – dynamic control (trainings with endurance swimming), Group 3 – trainings and BCAA, Group 4 – trainings and laser exposure at hip muscles (970 nm, 1 W, 60 s), Group 5 – combined exposure to laser and BCAA. Trainings were three times a week for 6 weeks; laser session was after each training. Samples of the bipedal thigh muscle were fixed with formalin; histological sections were stained with hematoxylin-eosin. The morphometric analysis of the digital image of objects with statistical processing by Mann – Whitney method was made.Results. Laser exposure combined with BCAA during trainings increased the nuclei area and the number of myosatellites and myocytes; it also enlarged the cross section of muscle fibers which was more pronounced if to compare with isolated laser irradiation of the muscle or BCAA.Conclusions. Infrared laser exposure in combination with branched-chain amino acids effectively stimulates regeneration due to hyperplasia and hypertrophy of skeletal muscular tissue, thus providing physiological adaptation in the training process.

Objective: to find evidence of the existence of distant lymphocytic RNA control of physiological myogenesis as a way to control the muscle tissue regeneration process.Materials and methods. The study was conducted on male Wistar rats, n=33. In the first part of the experiment, 12 rats were subjected to regular 40-day physical activity (swimming), half of them were intraperitoneally injected 4 times with total RNA isolated from pig spleen lymphocytes at 30 days of age; 6 rats made up the intact control group. In histological preparations of different skeletal muscle groups, the width and cross-sectional area of muscle fibers, the area of nuclei, and the number of myocytes and myosatellite cells were evaluated. In the second part of the experiment, 15 intact rats were injected with the studied xenogeneic RNA and the amounts of ribonucleic acids in peripheral blood lymphocytes, spleen lymphocytes, and skeletal muscles were determined 2 hours and 24 hours after injection.Results. After the 40- day physical activity, the width of the fibers and the area of myocyte nuclei in the skeletal muscles increased; the absolute number of myosatellite cells and the area of their nuclei did not change. After administration of xenogenic RNA in the trained rats, in addition to an increase in the thickness and cross-sectional area of muscle fibers, the absolute number of myosatellite cells in m. biceps femoris, in m. triceps brachii, and in m. pectoralis major increased 1.4-fold, 1.3-fold, and 1.4-fold, respectively; the area of myosatellite nuclei increased on average by 7%. In intact rats, two hours after xenogeneic RNA injection, the amount of RNA in skeletal muscles remained unchanged, it increased by 19% in spleen lymphocytes, and by 16% in peripheral blood lymphocytes. At 24 hours, the RNA amount in the lymphocytes remained significantly higher than the control values, while in the muscle tissue, it didn’t differ from the control.Conclusion. Xenogeneic lymphocytic RNA stimulates physiological myogenesis by activating myosatellite cell proliferation.

The aim of the work was to study the effect of laser exposure on the morphometric parameters of myosatellitocytes and myocytes during swimming training. Material and methods. The experiment was performed on 18 rats, divided into groups: 1) control, 2) swimming training 3) swimming training with infrared laser action on the muscles of the hind limbs. Samples of the biceps femoris were fixed with formalin and histological sections were prepared. A morphometric analysis of the digital image of objects was carried out. Results. Swimming training led to an increase in the number of myosatellites, the area of the nuclei of myosatellites and myocytes, and the cross-section of muscle fibers. Laser effect on muscle tissue during training contributed to a significantly greater increase in the studied parameters and an increase in the number of myocytes. Findings. The laser effect during swimming training stimulates the proliferative capabilities of muscle tissue.