ABSTRACT
Introdução: A cicatrização de feridas é um processo dinâmico que envolve vários elementos celulares com propósito de restabelecer a funcionalidade do tecido lesado, muitos fatores podem interferir neste processo tornando-o complexo. O laser e a microcorrente são modalidades terapêuticas que otimizam o processo de reparo, porém são estudadas isoladas. Objetivo: Investigar a eficácia da associação da fototerapia (laser, GaAlAs, λ 656±5 nm) com a eletroterapia (microcorrente) na cicatrização por segunda intenção em ratos. Método: Foram utilizados 15 ratos submetidos à lesão dorsal direita com 8 mm de diâmetro divididos em três grupos (n=5), nominados de GC (controle), G2 (laser +30µA) e G3 (laser +160 µA). Para análises histopatológicas foi determinado p≤0,05. Resultados: A análise estatística revelou que a área de colágeno apresenta-se estatisticamente superior nos grupos tratados (G2 e G3) quando comparados com o grupo controle. Conclusão: A associação das modalidades induz ao aumento do colágeno na fase inicial do reparo tecidual.
Introduction: Wound healing is a dynamic process that involves multiple cellular elements with the purpose of restoring the functionality of the injured tissue. Many factors can interfere with this process, making it complex. Laser and microcurrent are therapeutic strategies that optimize the repair process, but have been studied in isolation. Objective: To investigate the efficacy of combining phototherapy (laser, GaAlAs, λ 656±5 nm) with electrotherapy (microcurrent) on second intention healing in rats. Methods: We used 15 rats with 8 mm in diameter lesions in the right dorsal. The rats were divided into three groups (n = 5): the CG (control group), G2 (laser+30µA) and G3 (laser +160µA). For histopathological analysis p ≤ 0.05 was determined. Results: Statistical analysis revealed that the area of collagen was statistically higher in the treated groups (G2 and G3) compared with the control group. Conclusion: A combination of methods induces increased collagen in the initial phase of tissue repair.
Subject(s)
Animals , Male , Rats , Wounds and Injuries/radiotherapy , Electric Stimulation Therapy/methods , Low-Level Light Therapy/methods , Wound Healing , Collagen/physiology , Rats, WistarABSTRACT
Background: The effectiveness of low-level laser therapy in muscle regeneration is still not well known. Objective: To investigate the effects of laser irradiation during muscle healing. Method: For this purpose, 63 rats were distributed to 3 groups: non-irradiated control group (CG); group irradiated at 10 J/cm² (G10); and group irradiated at 50 J/cm² (G50). Each group was divided into 3 different subgroups (n=7), and on days 7, 14 and 21 post-injury the rats were sacrificed. Results: Seven days post-surgery, the CG showed destroyed zones and extensive myofibrillar degeneration. For both treated groups, the necrosis area was smaller compared to the CG. On day 14 post-injury, treated groups demonstrated better tissue organization, with newly formed muscle fibers compared to the CG. On the 21st day, the irradiated groups showed similar patterns of tissue repair, with improved muscle structure at the site of the injury, resembling uninjured muscle tissue organization. Regarding collagen deposition, the G10 showed an increase in collagen synthesis. In the last period evaluated, both treated groups showed statistically higher values in comparison with the CG. Furthermore, laser irradiation at 10 J/cm2 produced a down-regulation of cyclooxygenase 2 (Cox-2) immunoexpression on day 7 post-injury. Moreover, Cox-2 immunoexpression was decreased in both treated groups on day 14. Conclusions: Laser therapy at both fluencies stimulated muscle repair through the formation of new muscle fiber, increase in collagen synthesis, and down-regulation of Cox-2 expression. .