臨床整形外科48巻12号

2013年12月発行

誌上シンポジウム 慢性疼痛と原因療法―どこまで追究が可能か

P2X受容体を介した慢性疼痛メカニズムと鎮痛

著者： 谷口亘¹ 吉田宗人² 中塚映政¹

所属機関： ¹関西医療大学疼痛医学分野 ²和歌山県立医科大学整形外科学教室

ページ範囲：P.1169 - P.1174

　アデノシン三リン酸(ATP)とそのサブファミリー受容体のP2X受容体は慢性疼痛の形成に関して多彩に影響することが示唆されている．ATPは末梢レベルのP2X受容体に作用することで末梢性感作を引き起こし，脊髄後角レベルにおけるP2X受容体に作用することで中枢性感作を惹起し，さらには脊髄内の活性化グリア細胞に対して作用することでアロディニアの発症に関与している．このようにP2X受容体はさまざまな面で難治性である慢性疼痛の形成に関与しており，今後，P2X受容体を介した鎮痛の臨床応用が期待できる．

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