title: Temporal expression of immunoreactivity for heat shock protein 25 (Hsp25) in the rat periodontal ligament following transection of the inferior alveolar nerve.
abstract: The present study examined the immunohistochemical localization of heat shock protein 25 (Hsp25) during the regeneration of nerve fibers and Schwann cells in the periodontal ligament of the rat lower incisor following transection of the inferior alveolar nerve. In the untreated control group, the periodontal ligament of rat incisor did not contain any Hsp25-immunoreaction. On postoperative day 3 (PO 3d), a small number of Schwann cells with slender cytoplasmic processes exhibited Hsp25-immunoreactivity. From PO 5d to PO 21d, Hsp25-positive nerve fibers and Schwann cells drastically increased in number in the alveolar half of the ligament. Although the axons of some regenerating Ruffini-like endings also showed Hsp25-immunoreactions, the migrated Schwann cells were devoid of Hsp25-immunoreaction. Thereafter, Hsp25-positive structures decreased in number gradually to disappear from the periodontal ligament by PO 56d. This temporal expression of Hsp25 in the periodontal ligament well-reflected the regeneration process of the nerve fibers. Hsp25 in the regenerating nerve fibers and denervated Schwann cells most likely serves in modulating actin dynamics and as a cellular inhibitor of apoptosis, respectively.
authors.affiliation: Division of Oral Anatomy, Department of Biological Science, Niigata University Graduate School of Medical and Dental Sciences, 2-5274 Gakkocho-dori, 951-8514, Niigata, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Iijima
authors.forename: Fumiko
authors.initials: F
authors.lastname: Harada
authors.forename: Kooji
authors.initials: K
authors.lastname: Hanada
authors.forename: Kayoko
authors.initials: K
authors.lastname: Nozawa-Inoue
authors.forename: Megumi
authors.initials: M
authors.lastname: Aita
authors.forename: Yukako
authors.initials: Y
authors.lastname: Atsumi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Wakisaka
authors.forename: Takeyasu
authors.initials: T
authors.lastname: Maeda
mesh_terms: D000818:Animals; D019771:Axotomy; D006360:Heat-Shock Proteins / Q000378:metabolism*; D007150:Immunohistochemistry; D008340:Mandibular Nerve / Q000601:surgery*; D009416:Nerve Regeneration / Q000502:physiology; D010513:Periodontal Ligament / Q000294:innervation / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012583:Schwann Cells / Q000378:metabolism
chemical_list: D006360:Heat-Shock Proteins