title: Altered expression level of calbindin D28k in the periodontal ligament of rat molar in response to changes in occlusal force.
abstract: The present immunohistochemical study was designed to investigate the alteration in the expression level of calbindin D28k in the periodontal ligament of the rat molar in response to changes in occlusal force to clarify the physiological role(s) of this protein in the ligament. In normal periodontal ligament of the lower first molar, immunoreactivity for calbindin D28k was found in the spindle-shaped cells, presumably fibroblasts, at the alveolar portion of the ligament at the distal side of the mesial root and mesial side of the distal root. Following the overload of occlusal force to the upper first molar by bite-raising, the number and immunoreactivity of the positive cells in the periodontal ligament of the lower first molar increased gradually. A more significant increase was detected at 7 d following the bite-raising compared to the normal animals. When occlusal force was removed by the extraction of the upper first molar, the expression level of calbindin D28k in the periodontal ligament of the lower first molar rapidly decreased, however a subsequent gradual increase was recognized. Statistical analysis of the spatial immunoreactivity of calbindin D28k in the periodontal ligament was performed and showed statistically significant differences. The present results suggest that calbindin D28k may play important roles in the homeostasis and cytoprotection of the periodontal fibroblasts against occlusal force.
authors.affiliation: Department of Oral Anatomy and Development Biology, Osaka University Faculty of Dentistry, Suita, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Onishi
authors.forename: T
authors.initials: T
authors.lastname: Ooshima
authors.forename: S
authors.initials: S
authors.lastname: Sobue
authors.forename: A
authors.initials: A
authors.lastname: El-Sharaby
authors.forename: K
authors.initials: K
authors.lastname: Kurisu
authors.forename: S
authors.initials: S
authors.lastname: Wakisaka
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001732:Bite Force; D064092:Calbindin 1; D064026:Calbindins; D003799:Dental Stress Analysis; D005347:Fibroblasts / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D008334:Mandible; D008963:Molar; D010513:Periodontal Ligament / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D064030:S100 Calcium Binding Protein G / Q000096:biosynthesis* / Q000502:physiology*; D018709:Statistics, Nonparametric
chemical_list: C576500:Calb1 protein, rat; D064092:Calbindin 1; D064026:Calbindins; D064030:S100 Calcium Binding Protein G