Diferentes efeitos de duas doses de laser de baixaintensidade em modelos experimentais de inflamação

Abstract

Introduction: The Low-intensity laser therapy (LBI) is a widely used therapeutic procedure in the clinical setting, considering its biological effects on the tissue in a non-thermal way and being an

effective therapeutic option and with fewer side effects compared to conventional therapy With anti- inflammatory drugs. Despite the clinical effects already reported in several studies, its mechanism

of action and dosimetric parameters are not fully understood, with great divergence on dose and effect. Thus, studies on dosimetry are important and necessary to form subsidies for effective treatment. Objectives: To describe the effect of two different doses of Low Intensity Laser on experimental models of inflammation. Method: Swiss mice were distributed in 4 groups in different experiments, Salina Group (received only 0.9% saline injection); Group that received phlogiston agent (Cg, dextran, serotonin, histamine or bradykinin); Laser Group 1 (received the injection of flogistic agent and treatment with Laser 1J / cm2 (L1) and Group Laser 5 (L5 received flogistic agent and treatment with Laser 5J / cm2). Paw volume variation, myeloperoxidase action (MPO) and histological analysis were evaluated. An experiment with induction of carrageenan peritonitis was also carried out. Vascular permeability, myeloperoxidase action (MPO), glutathione dosage (GSH), malondialdehyde dosage (MDA) and neutrophil migration. Results: We obtained reduction in all edemas with laser treatment at the dose of 1J / cm2 and reduction of histological scores. In addition to decreased neutrophil migration and Malondialdehyde levels (MDA), as well as preservation in Glutathione (GSH) levels. However, the same was not obtained with the 5J / cm 2 dose for vascular edema (dextran and histamine), vascular permeability and carrageenan edema. Conclusion: These results suggest that laser at the dose of 1J / cm2 has a cellular and vascular character, since it was able to revert all edema and analysis of peritonitis; and the Laser at a dose of 5J / cm2 possibly only has a cellular character in acute inflammation.