Ultrastructural visualization and partiai characterization of extracellular matrices in the stellate reticulum of kitten tooth germs

• Published in: Japanese Journal of Oral Biology Vol. 45; no. 5; p. 337
• Main Authors: 小萱康徳, 岩久文彦
• Format: Journal Article
• Language: English; Japanese
• Published: Japanese Association for Oral Biology 01.09.2003; 歯科基礎医学会
• ISSN: 0385-0137

The stellate reticulum (SR), characterized by wide intercellular spaces, contains abundant extracellular matrices (EGMs) including glycosaminoglycans(GAGs). We examined the ultrastructural localization of ECMs in the SR of kitten tooth germs using histochemical (HID) and immunohistochemical (HABP) techniques in combination with enzymatic degradation. At light microscopic level the ECMs were observed as a network of filamentous structures (FS). The FS arranged perpendicular to the plasmalemma of macrophages, and no PS were observed in the immediate vicinity of the stratum intermedium prior to enamel formation, but granular dense materials (GDMs) were interspersed. HID stain deposits were detected preferentially in some of these GDMs, but there were few over the FS. In contrast, hyaluronate was widely distributed in the SR associated with the FS. Most PS in the inner half layer of the SR were sensitive for hyaluronidases. Those in the outer half layer resisted enzymatic degradation. These findings indicate that there are regional differences in ECM composition of the SR and that hyaluronate and chondroitin sulfates are co-localized in the GDMs.