title: Effect of minocycline on induced glial activation by experimental tooth movement.
abstract: BACKGROUND
  Orthodontic tooth movement causes pain to a patient. Glial cells are nonneuronal cells in the central nervous system and are implicated in various types of pain. In this study, we assessed glial activation responses after experimental tooth movement using immunocytochemical detection of anti-CD11b (OX42) and glial fibrillary acidic protein immunoreactivity to illustrate the microglial and astrocytes response, respectively. In addition, the effect of minocycline in reducing pain during tooth movement was also investigated.
  
  
  METHODS
  Fifty-five Sprague Dawley rats with and without administration of minocycline after 1, 3, 5, 7, and 14 days (n = 5, for each) of tooth movement were used. Immunohistochemistry for microglia (OX42) and astrocyte (glial fibrillary acidic protein) were performed at the medullary dorsal horn (trigeminal subnucleus caudalis). Three-dimensional quantitative analysis was performed with a confocal fluorescence microscope and a software program.
  
  
  RESULTS
  There was a significant increase in the OX42 and glial fibrillary acidic protein immunoreactivity in response to tooth movement in the medullary dorsal horn. Furthermore, systematic administration of minocycline, a selective inhibitor of microglial activation, significantly attenuated the nociceptive c-Fos expression in the medullary dorsal horn that was induced by experimental tooth movement.
  
  
  CONCLUSIONS
  These data indicate the possible importance of microglial activation in the development of orthodontic pain. This is also the first report on the systematic application of minocycline.
authors.affiliation: Associate professor, Division of Orthodontics, College of Dentistry, Ohio State University, Columbus, Ohio. Electronic address: deguchi.4@osu.edu.
authors.forename: Toru
authors.initials: T
authors.lastname: Deguchi
authors.affiliation: Research fellow, Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
authors.forename: Rie
authors.initials: R
authors.lastname: Adachi
authors.affiliation: Professor and chair, Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kamioka
authors.affiliation: Associate professor, Division of Orthodontics, College of Dentistry, Ohio State University, Columbus, Ohio.
authors.forename: Do-Gyoon
authors.initials: DG
authors.lastname: Kim
authors.affiliation: Professor and chair, Division of Orthodontics, College of Dentistry, Ohio State University, Columbus, Ohio.
authors.forename: Henry W
authors.initials: HW
authors.lastname: Fields
authors.affiliation: Professor and chair, Division of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Tohoku University, Sendai, Japan.
authors.forename: Teruko
authors.initials: T
authors.lastname: Takano-Yamamoto
authors.affiliation: Professor and chair, Division of Oral and Craniofacial Anatomy, Graduate School of Dentistry, Tohoku University, Sendai, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ichikawa
authors.affiliation: Professor and Chair, Department of Orthodontics, Graduate School of Dentistry, Osaka University, Osaka, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamashiro
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000187:drug effects* / Q000502:physiology*; D017628:Microglia / Q000187:drug effects* / Q000502:physiology*; D008911:Minocycline / Q000627:therapeutic use*; D010146:Pain / Q000209:etiology* / Q000517:prevention & control*; D017207:Rats, Sprague-Dawley; D014087:Tooth Movement Techniques / Q000009:adverse effects*
chemical_list: D008911:Minocycline