アブストラクト(23巻4号:神奈川歯学)

神奈川歯学

Japanese

Title : マウス胎仔培養頭頂骨片における初期石灰化の微細構造学的研究
Subtitle : 原著
Authors : 大城隆, 高橋和人
Authors(kana) :
Organization : 神奈川歯科大学口腔解剖学教室
Journal : 神奈川歯学
Volume : 23
Number : 4
Page : 469-485
Year/Month : 1989 / 3
Article : 原著
Publisher : 神奈川歯科大学学会
Abstract : 「序論」生体の石灰化(biological mineralization)は生理的あるいは病的状態下での生体中への無機質の沈着現象として定義づけられている. ミネラルの主成分がカルシウムである哺乳類では, 一般にmineralizationとcalcification(石灰化)が一義的に用いられている. 最近になって, この石灰化がin vitro条件下でコントロールが可能になり, 石灰化機構に関して多くの情報が与えられるようになったが, その実体については以前と不明の部分が多い. 石灰化機構の解釈は, 歴史的にみると諸説がある. 古くは, 1932年のRobinsonによるアルカリ性ホスファターゼ説で, 石灰化組織局所における活性度の高いリン酸エステラーゼの存在, 局所のカルシウムあるいはリン酸濃度の上昇が無機塩の沈澱を起こすというものである. 次に, コラーゲン線維を主体とする基質成分に石灰化の特異性を求めたNeuman and Neuman (1958) のエピタキシー説などが提起されていたが, いづれも複雑な機構のごく一部について述べているにすぎなかった.
Practice : 歯科学
Keywords : 骨芽細胞, 石灰化, 培養, 頭頂骨, 微細構造

English

Title : Ultrastructural studies of initial calcification of mouse fetal parietal bone in vitro
Subtitle : Original article
Authors : Takashi OSHIRO, Kazuto Takahashi
Authors(kana) :
Organization : Department of Oral Anatomy Kanagawa Dental College
Journal : Kanagawa Shigaku
Volume : 23
Number : 4
Page : 469-485
Year/Month : 1989 / 3
Article : Original article
Publisher : Kanagawa Odontological Society
Abstract : Abstract : The parietal bone fragment (1.5mm square) extracted from murine fetal calvaria (periosteum was removed) in the latter stage of gestation was cultured in α-MEM containing 10% fetal bovine serum over 10-day period, and the initial calcification site was subsequently examined utilizing both electron microscopy and histochemical methods. At the initial calcification site, the so-called "matrix vesicle" (width 100nm), derived from osteoblasts which induce matrix formation, and the larger vesicular structures (width 100-600nm) which originated from degenerated or dead cells were observed. Additionally dead osteoblast-like cells phagocytosing bone crystals particicipated in bone nodul formation. In the border region between the degenerated or disrupted cells and the functioning cells, multilamellar structures (mainly composed of phospholipids) were frequently observed. Concurrently it was concluded that there is a possibility of partial deposition of calcium salts on the surface of the above mentioned cells under some circumstances. Throught selective decalcification, it was determined that bone trabecule was formed by fusion of respective bone noduli and degraded collagen fibrils which filled the intervening spaces. From the above results, it was evident that both the matrix vesicles derived from functioning osteoblast, and the vesicular structures derived from the degenerated or dead cells concurrently phagocytosing spicules and collagen fibrils were involved in the initial calcification process of the membranous bone in vitro.
Practice : Dentistry
Keywords :