title: Effect of nitric oxide on the recovery of the hypofunctional periodontal ligament.
abstract: The relationship between occlusal stimuli and a hypofunctional periodontal ligament (PDL) structure has been reported, though changes in occlusal recovery conditions were still unclear. Nitric oxide (NO) produced by NO synthase (NOS) is considered a factor for vascular and immune system control, and it increases according to mechanical stimuli. The objective of this study was to examine the relationship between NOS and occlusal stimuli in PDL by comparing hypofunction with occlusal recovery. The study focused on the expression of endothelial NOS (eNOS) and inducible NOS (iNOS). Their expression significantly decreased in occlusal hypofunction compared with the control group and increased close to normal in an occlusal recovery group. The change in the immunopositive area was more dramatic than the immunopositive cell number. Moreover, the rate of iNOS increase was higher than that of eNOS. This study suggests that NO plays an important role in the recovery of the hypofunctional PDL.
authors.affiliation: Orthodontic Science, Department of Orofacial Development and Function, Division of Oral Health Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan. watarai.orts@tmd.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Watarai
authors.forename: H
authors.initials: H
authors.lastname: Warita
authors.forename: K
authors.initials: K
authors.lastname: Soma
mesh_terms: D000818:Animals; D001732:Bite Force; D042783:Endothelial Cells / Q000201:enzymology; D007150:Immunohistochemistry; D008297:Male; D008409:Mastication / Q000502:physiology*; D008437:Maxilla; D008963:Molar / Q000098:blood supply; D009569:Nitric Oxide / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D010513:Periodontal Ligament / Q000098:blood supply / Q000201:enzymology* / Q000473:pathology; D011312:Pressure; D051381:Rats; D017207:Rats, Sprague-Dawley; D013314:Stress, Mechanical
chemical_list: D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; C496318:Nos2 protein, rat; C496316:Nos3 protein, rat