title: Duration-dependent effects of the bite-raised condition on hippocampal function in SAMP8 mice.
abstract: We evaluated the effect of the duration of occlusal disharmony induced chronic stress on hippocampal function by examining spatial memory in the Morris water maze and on the number of hippocampal neurons in aged senescence-accelerated prone (SAMP8) mice. The bite of SAMP8 mice was raised 0.1 mm using dental adhesive. Groups of mice were tested in the Morris water maze 8, 11, or 22 d after raising the bite. The results indicated that the longer the duration of the bite-raised condition, the greater the impairment in spatial learning ability and the greater the decrease in the number of neurons in the hippocampal CA3 subfield. Thus, behavioral and morphologic deficits induced by the bite-raised condition in aged SAMP8 mice are influenced by the duration of the occlusal disharmony.
authors.affiliation: Department of Pediatric Dentistry, 1851-1 Hozumi, Mizuho, Gifu, 501-0296, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Arakawa
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Ichihashi
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Iinuma
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Tamura
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Iwaku
authors.forename: Kin-Ya
authors.initials: KY
authors.lastname: Kubo
mesh_terms: D000818:Animals; D002452:Cell Count; D016923:Cell Death; D003769:Dental Occlusion, Traumatic / Q000523:psychology; D004195:Disease Models, Animal; D006624:Hippocampus / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D018782:Maze Learning / Q000502:physiology; D008569:Memory Disorders / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology*; D051379:Mice; D008817:Mice, Mutant Strains; D009410:Nerve Degeneration / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology*; D009474:Neurons / Q000473:pathology; D013315:Stress, Psychological / Q000150:complications*; D013997:Time Factors