Динамика гиперхромных и MyoD-позитивных ядер регенерирующих скелетных мышц при инфракрасной фотомодуляции

Abstract

Introduction. Currently, there are no techniques that allow to fully restore skeletal muscle tissue after injury. Infrared laser exposure is a universal physiotherapeutic method used to activate proliferation, increase enzyme activity, and reduce inflammation and edema. At the same time, the influence of the exposure time of infrared laser irradiation on the activation of myosatellite cells has been poorly studied. The paper aimed to analyze the effect of the duration of infrared laser irradiation on the state of cambial reserve cells in regenerating skeletal muscle tissue. Materials and methods. In the experiment (128 male Wistar rats), 4 groups were formed: 0 – intact group; I (dynamic control) – incised wound m. gastrocnemius; II – laser irradiation of the wound with a 60- second exposure; and III – laser irradiation of the wound with a 180-second exposure.The laser was used in a continuous mode, the power being 1.0 W. We performed a morphological study of the area of hyperchromatic muscle nuclei and the density of MyoD+ nuclei at different periods of the experiment. Results. In group III, the area of hyperchromatic nuclei decreased on day 1, and on day 7, it was 30% more than in group I. The density of the arrangement of MyoD+ nuclei in groups II and III increased compared to that in group I for a period of 3 days, regardless of the exposure time. However, on day 7, the number of nuclei was greater in group II. Conclusion. After the use of an infrared laser with a 60-second exposure, the density of MyoD+ nuclei increases, whereas the effect of a 180-second laser exposure has a more dramatic effect on the increase in the area of hyperchromic nuclei of muscle tissue.