OA-6

Runx2 expression in mandibular condylar cartilage development

Takako Shimizu¹, Hitoshi Nagatsuka², Hidetsugu Tsujigiwa², Takehiro Watanabe¹, Norimasa Okafuji¹, Saburo Kurihara¹, Noriyuki Nagai², and Toshiyuki Kawakami¹

¹Matsumoto Dental University

²Okayama University

The purpose of this study was to investigate the expression pattern of Runx2 in mandibular condylar cartilage, a type of secondary cartilage.  Mandibular condyles of ddY mice were fixed from embryonic days E14 to E18, and just after birth (equivalent to E19).  Immunohistochemistry(IHC) and in situ hybridization(ISH) results for E14 showed Runx2 expression in coagulating mesenchymal cells.  In both IHC and ISH results after E17, Runx2 factors appeared in the cells of the condylar cartilage sheath. These results suggest that Runx2 plays an essential role for mandibular condylar cartilage development.