title: Low-level laser therapy modulates cyclo-oxygenase-2 expression during bone repair in rats.
abstract: The goal of this study was to analyze the role of cyclo-oxygenase-2 following bone repair in rats submitted to low-level laser therapy. A total of 48 rats underwent surgery to inflict bone defects in their tibias having been randomly distributed into two groups: negative control and laser exposed group, i.e., the animals were treated with low-level laser therapy by means of gallium arsenide laser at 16 J/cm(2). The animals were killed after 48 h, 7 days, 14 days, or 21 days. The tibias were removed for morphological, morphometric, and immunohistochemistry analysis for cyclo-oxygenase-2. Statistical significant differences (P < 0.05) were observed in the quality of bone repair and quantity of formed bone between groups 14 days after surgery in the laser exposed group. In the same way, cyclo-oxygenase-2 immunoreactivity was more intense in bone cells for intermediate periods evaluated in this group. Taken together, such results suggest that low-level laser therapy is able to improve bone repair in the tibia of rats after 14 days of surgery as a result of an up-regulation for cyclo-oxygenase-2 expression in bone cells.
authors.affiliation: Department of Oral Maxillofacial Surgery, School of Dentistry, University of the Sacred Heart (USC), Bauru, SP, Brazil.
authors.forename: Mariza A
authors.initials: MA
authors.lastname: Matsumoto
authors.forename: Rafael V
authors.initials: RV
authors.lastname: Ferino
authors.forename: Giovanni F
authors.initials: GF
authors.lastname: Monteleone
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Ribeiro
mesh_terms: D000818:Animals; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D004195:Disease Models, Animal; D017102:Fracture Healing / Q000502:physiology / Q000528:radiation effects*; D054023:Lasers, Semiconductor / Q000627:therapeutic use*; D028022:Low-Level Light Therapy; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013978:Tibial Fractures / Q000201:enzymology* / Q000473:pathology / Q000532:radiotherapy*; D013997:Time Factors
chemical_list: D051546:Cyclooxygenase 2