アブストラクト（30巻3号：神奈川歯学）

神奈川歯学

Japanese

Title　： ラット臼歯形態形成における接着装置の形成とその機能
Subtitle　： 原著
Authors　： 岩瀬峰代*,**, 佐々昭三*, 渡邉是久**
Authors（kana）　：
Organization　： *神奈川歯科大学口腔組織学教室, **神奈川歯科大学口腔病理学教室
Journal　： 神奈川歯学
Volume　： 30
Number　： 3
Page　： 241-257
Year/Month　： 1995 / 12
Article　： 原著
Publisher　： 神奈川歯科大学学会
Abstract　： 「緒言」 組織や器官の形態形成運動時において, 細胞は細胞分裂を繰り返しながらそれらの配置をダイナミックに変化させ, さらに細胞は分化を開始し, その機能を発現するようになる. ラット臼歯歯胚においても, エナメル器の内エナメル上皮細胞がエナメル芽細胞に分化し, 歯乳頭側の間葉細胞が象牙芽細胞に分化していく鐘状期に, 将来の歯冠の形態が決定されることが観察されている. 歯胚発生過程では上皮-間葉間に存在する基底膜構成蛋白質が内エナメル上皮細胞や間葉細胞の分化を促し, 種々の細胞外基質や成長因子が細胞増殖の調節に関与している. また, 歯冠形態の形成機構については, 内エナメル上皮細胞の外エナメル上皮細胞側への突出は, 星状網の陥凹によって決定されるか, あるいは部位によって内エナメル上皮細胞の細胞分裂の終了時期に差があり, 引き続いて生じる分化段階に部位的差異を生じることから決定されると考えられている.
Practice　： 歯科学
Keywords　： 歯冠, ラット臼歯, 形態形成, カドヘリン, F-アクチン

English

Title　： The Study of Formation and Function on Intercellular Junction in Morphogenesis of Rat Molars
Subtitle　： Original article
Authors　： Mineyo IWASE*,**, Shozo Sasa*, Yoshihisa Watanabe**
Authors（kana）　：
Organization　： *Department of Oral Histology, Kanagawa Dental College, **Department of Oral Pathology, Kanagawa Dental College
Journal　： Kanagawa Shigaku
Volume　： 30
Number　： 3
Page　： 241-257
Year/Month　： 1995 / 12
Article　： Original article
Publisher　： Kanagawa Odontological Society
Abstract　： Abstract : Immunohistochemical analysis was performed to a system to examine the tooth-crown morphogenesis of rat molars. The auther examined the interrelation between localization of P-cadherin (cell adhesion molecule) and that of cytoskeleton in the development of the tooth germ. The auther detected P-cadherin which was connected with cytoskeleton by using Triton X-100 treatment, and examined changes in localization. In the tooth germ at an early stage of development, P-cadherin was localized at the proximal end of the inner enamel epithelium of the cervical loop and cleft. In the inner enamel epithelium of other parts, P-cadherin was localized in the cell circumference. A major part of the localization of P-cadherin in these tooth germ was not observed after Triton x-100 treatment. In the tooth germ mentioned above, the inner enamel epithelium had cell division ability, and intense positive reaction of cytoskeleton was not observed. These findings suggested that P-cadherin which disappeared by Triton X-100 treatment participated in loose adhesion among the cells. In the tooth germ of more progressed phase development, a positive reaction of P-cadherin was observed at the proximal end in the differentiation stage ameloblasts, and was observed at the proximal end and distal end in the secretory stage ameloblast. The positive reaction of these P-cadherin remained after Triton X-100 treatment. α-Actinin and F-actin were observed in the same location as P-cadherin. This suggested that P-cadherin which remained there formed an adherence junction and participated in a good adhesion. In this way, the type of cell adhesion was changed with the differentiation of tooth germ and ameloblast. The variety of adhesion form in the enamel organ causes a difference in the adhesive strength in each location. The difference of this adhesive strength settles in the direction to which the inner enamel epithelium bends, and then the folding of inner enamel epithelium seems to occur. Mutual mechanical avidity is maintained by a junctional complex, and crown form will be settled when it starts secretion of dental enamel furthermore. Therefore, the ability of cell division and changing of interrelation between cell adhesion malecule and cytoskeleton has a primary role in the morphogenesis of the crown.
Practice　： Dentistry
Keywords　：