Efeito de diferentes doses, comprimentos de onda e intervalos de aplicação da laserterapia de baixa potência na atividade de citocromo c-oxidase em diferentes tipos de fibras musculares no músculo esquelético de ratos

Abstract

Over the years modulation of cytochrome c-oxidase has been pointed as key-mechanism in interaction between LASER radiation with different biological tissues. More recently, a study demonstrated that cytochrome c-oxidase activity is increased by phototherapy in different types of skeletal muscle fibers of rats. Recent studies of our research group with phototherapy have shown positive results delaying skeletal muscle fatigue and improving the status of biochemical markers related to skeletal muscle recovery when these therapies were applied before exercise. We think that cytochrome c-oxidase activity can play a key role in low-level laser therapy (LLLT) effects in delaying skeletal muscle fatigue. With these perspectives in mind, this research project aimed to evaluate effects of different LLLT doses and wavelengths in cytochrome c-oxidase activity in different types of skeletal muscle fibers, as well as to determine time interval that occurs peak of activity of cytochrome c-oxidase in different types of skeletal muscle fibers. For such, we performed an animal experiment. In this experiment tibialis anterior muscle of rats were irradiated with different LLLT doses (1, 3 and 10 J), with different wavelengths (660, 830 and 905 nm), with 50 mW power output. After irradiation muscles were be removed at different experimental times (5, 10, 30 minutes, 1, 2, 12 and 24 hours) and were stored for further analysis. Analyses of cytochrome c-oxidase activity in different types of muscular fiber were performed through immunohistochemical analysis, with analysis of histological images. For the wavelengths and doses evaluated stood out as biostimulator, relations 660 nm/ 1J, 830 nm/ 3J and 905 nm/ 1J. The LBP is effective as the modulation of the expression of cytochrome c oxidase