title: Biting reduces acute stress-induced oxidative stress in the rat hypothalamus.
abstract: We investigated the inhibitory effect of para-masticatory activity, namely biting, on restraint stress-induced oxidative stress. A blood brain barrier-permeable nitroxyl spin probe, 3-methoxycarbonyl-2,2,5,5,-tetramethylpyrrolidine-1-oxyl (MC-PROXYL), was administered to rats and L-band electron spin resonance (ESR) and ESR-computerized tomography (ESR-CT) imaging were used to show that the decay rate constant of MC-PROXYL in the hypothalamus of isolated brain after 30 min of restraint stress was more rapid than in unrestrained control rats, suggesting that restraint was associated with oxidative stress. Interestingly, biting during restraint stress caused the decay rate constant of MC-PROXYL in isolated brain to approach that of the control group. These observations suggest that biting suppresses oxidative stress induced by restraint stress, and that the anti-stress effect of masticatory motor activity movements, such as biting, are important for reducing the adverse effects associated with exposure to psychological stressors.
authors.affiliation: Department of Craniofacial Growth and Development Dentistry, Kanagawa Dental College, Yokosuka, Kanagawa, Japan.
authors.forename: Shinjiro
authors.initials: S
authors.lastname: Miyake
authors.forename: Kenichi
authors.initials: K
authors.lastname: Sasaguri
authors.forename: Norio
authors.initials: N
authors.lastname: Hori
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Shoji
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Yoshino
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Miyazaki
authors.forename: Kazunori
authors.initials: K
authors.lastname: Anzai
authors.forename: Nobuo
authors.initials: N
authors.lastname: Ikota
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Ozawa
authors.forename: Minoru
authors.initials: M
authors.lastname: Toyoda
authors.forename: Sadao
authors.initials: S
authors.lastname: Sato
authors.forename: Masaichi-Chang-il
authors.initials: MC
authors.lastname: Lee
mesh_terms: D000818:Animals; D001733:Bites and Stings / Q000503:physiopathology*; D001921:Brain / Q000000981:diagnostic imaging / Q000503:physiopathology; D004578:Electron Spin Resonance Spectroscopy; D007031:Hypothalamus / Q000000981:diagnostic imaging / Q000503:physiopathology*; D007275:Injections, Intravenous; D008297:Male; D018384:Oxidative Stress / Q000502:physiology*; D011759:Pyrrolidines / Q000008:administration & dosage / Q000493:pharmacokinetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D012149:Restraint, Physical; D013315:Stress, Psychological / Q000517:prevention & control*; D014057:Tomography, X-Ray Computed
chemical_list: D011759:Pyrrolidines