title: Proteomic analysis of the rat cerebellar flocculus during vestibular compensation.
abstract: Unilateral labyrinthectomy (UL) in rats is used as a human vertigo model. In this model, spontaneous nystagmus and dysequilibrium caused by UL are ameliorated within 48-72 hours. The amelioration, termed vestibular compensation (VC), is long lasting. Although cerebellar flocculi have been reported to be involved in VC, the molecular mechanisms behind VC are unknown. In this study, we used 2D-DIGE to detect protein changes in flocculi during acute (48 hours) and chronic (1 week) stages of VC. We found 99 out of 967 protein spots that showed significant changes in their intensities. Of the 99 spots, 45 spots (ipsilateral side, 15; contralateral side, 30) changed unilaterally during the acute stage, whereas 46 spots (ipsilateral side, 21; contralateral side, 25) changed unilaterally during the chronic stage. Thus, the acute compensation mechanism is more complicated in the contralateral flocculus than in the ipsilateral flocculus. Using MALDI-TOF MS, we identified 10 proteins out of the 12 protein spots. Of these, 3 proteins involved in synaptic transmission, neuronal filament formation and vesicular transport, respectively, demonstrated altered expression only in the acute stage. Our results enhance the understanding of the role of the cerebellar flocculi in VC generation.
authors.affiliation: Clinical Proteomics & Molecular Medicine, St. Marianna University Graduate School of Medicine, Kawasaki, Kanagawa, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Fukasawa
authors.forename: Kazuki
authors.initials: K
authors.lastname: Okamoto
authors.forename: Manabu
authors.initials: M
authors.lastname: Nakamura
authors.forename: Koshi
authors.initials: K
authors.lastname: Mikami
authors.forename: Sonoko
authors.initials: S
authors.lastname: Shimada
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Kouhei
authors.initials: K
authors.lastname: Nagai
authors.forename: Mitsumi
authors.initials: M
authors.lastname: Arito
authors.forename: Manae S
authors.initials: MS
authors.lastname: Kurokawa
authors.forename: Kayo
authors.initials: K
authors.lastname: Masuko
authors.forename: Naoya
authors.initials: N
authors.lastname: Suematsu
authors.forename: Izumi
authors.initials: I
authors.lastname: Koizuka
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Kato
mesh_terms: D000818:Animals; D002531:Cerebellum / Q000378:metabolism*; D007758:Ear, Inner / Q000601:surgery; D015180:Electrophoresis, Gel, Two-Dimensional; D007381:Intermediate Filament Proteins / Q000378:metabolism; D008297:Male; D052066:N-Ethylmaleimide-Sensitive Proteins / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009473:Neuronal Plasticity / Q000502:physiology*; D013506:Otologic Surgical Procedures; D019704:Protein Disulfide-Isomerases / Q000378:metabolism; D040901:Proteomics; D051381:Rats; D017207:Rats, Sprague-Dawley; D009435:Synaptic Transmission / Q000502:physiology; D014722:Vestibule, Labyrinth / Q000502:physiology*
chemical_list: D007381:Intermediate Filament Proteins; D009419:Nerve Tissue Proteins; C046643:alpha-internexin; D052066:N-Ethylmaleimide-Sensitive Proteins; D019704:Protein Disulfide-Isomerases