Sodium-Calcium Exchangers in Rat Ameloblasts

Journal of Pharmacological Sciences

Takashi Muramatsu¹  Kan-Ichi Nakagawa²  Masaki Shimono³  Yoshiyuki Shibukawa¹  Masakazu Tazaki¹  Reijiro Okumura¹  Sadamitsu Hashimoto¹ 

[1] Oral Health Science Center, hrc7, Tokyo Dental College, Japan;Department of Endodontics, Pulp and Periapical Biology, Tokyo Dental College, Japan;Department of Pathology, Tokyo Dental College, Japan

关键词: transporter;    enamel;    mineralization;    channel;    SLC8 gene family;   

DOI  :  10.1254/jphs.09267FP

学科分类：药学

来源: Nihon Yakuri Gakkai Henshuubu / Japanese Pharmacological Society

【 摘 要 】

References(33)Cited-By(12)Although the central role of ameloblasts in synthesis and resorption of enamel matrix proteins during amelogenesis is well documented, the Ca2+-transport/extrusion mechanism remains to be fully elucidated. To clarify Ca2+-transport in rat ameloblasts, we investigated expression and localization of Na+-Ca2+ exchanger (NCX) isoforms and the functional characteristics of their ion transporting/pharmacological properties. RT-PCR and immunohistochemical analyses revealed expression of NCX1 and NCX3 in ameloblasts, localized in the apical membrane. In patch-clamp recordings, Ca2+ efflux by Na+-Ca2+ exchange showed dependence on external Na+. Ca2+ influx by Na+-Ca2+ exchange, measured by fura-2 fluorescence, showed dependence on extracellular Ca2+ concentration, and it was blocked by NCX inhibitors KB-R7943, SEA0400, and SN-6. These results showed significant expression of NCX1 and NCX3 in ameloblasts, indicating their involvement in the directional Ca2+ extrusion pathway from cells to the enamel mineralizing front.

【 授权许可】

Unknown