Effect of photobiomodulation therapy (660 nm and 830 nm) on carrageenan-induced edema and pain behavior in mice

Abstract

BACKGROUND AND OBJECTIVES: Photobiomodulation (PBM) is an important therapeutic tool for inflammatory process modulation. In this study, the anti-inflammatory and analgesic effect of two different energies and two different wavelengths (660 nm and 830 nm) were investigate and compared through the model of carrageenan-induced paw edema in mice. METHODS: Male Swiss mice, 36 animals (n=6 animals/group) were divided into six groups: Group 1 (saline-control), Group 2 (carrageenan), Group 3 (carrageenan + laser 660 nm, 5.88 J), Group 4 (carrageenan + laser 660 nm, 2.94 J), Group 5 (carrageenan + laser 830 nm, 5.88 J), and Group 6 (carrageenan + laser 830 nm, 2.94 J). PBM was applied 1h after the carrageenan injection which induced paw edema and hyperalgesia, which were measured by means of a plethysmometer and by flicker test using a water bath at 38ºC (±0.5ºC), respectively. Left paws of mice injected with carrageenan exhibited local edema that persisted for up to 6h after its administration. All animals were evaluated before, 1, 2, 3, 4, and 6 h after the injection of carrageenan. Effect of photobiomodulation therapy (660 nm and 830 nm) on carrageenan-induced edema and pain behavior in miceEfeito da terapia por fotobiomodulação (660 nm e 830 nm) no comportamento da dor e edema induzidos por carragenina em camundongos