構成的なμ-オピオイド受容体活性により,長期的な内生性鎮痛症と依存性が生じます
G Corder1, S Doolen, R R Donahue
1Department of Physiology, University of Kentucky, Lexington, KY 40536, USA.
まとめ
組織損傷はμ-オピオイド受容体 (MORs) を活性化し,長期的な疼痛緩和を提供します. この活動をブロックすると,オピオイド離脱症状が発生し,MORが慢性疼痛の発症を予防することを示唆しています.
科学分野:
- 神経科学は神経科学である.
- 痛みの研究 痛みの研究
- 薬理学 薬理学とは
背景:
- オピオイド受容体は,急性疼痛を緩和することが知られている.
- 病理的な痛みの長期的オピオイド抑制の背後にあるメカニズムは完全に理解されていません.
研究 の 目的:
- 病理的な痛みの長期的オピオイド抑制のメカニズムを調査する.
- 疼痛シグナル伝達とオピオイド依存症におけるμ-オピオイド受容体 (MOR) 構成活性 (MOR) の役割を調査する.
主な方法:
- 動物モデルにおける組織損傷の誘導.
- 逆アゴニストを使用したMOR (CA) の薬理学的封鎖.
- 脊髄のノシセプティブシグナル伝達,疼痛感受性,離脱症状の評価.
主要な成果:
- 組織損傷が誘発された持続的なMOR ((CA),数ヶ月間脊髄の悪感信号を抑制する.
- MOR (CA) をブロックすると,痛みに対する感受性が回復し,オピオイド離脱症状が急増した.
- 離脱症状には,N-メチル-D-アスパルテート受容体のアデニリルサイクラゼ1型の活性化が含まれていた.
結論:
- MOR ((CA) は,鎮痛シグナル伝達と補償的なオピオイド依存プロセスの両方を媒介する.
- トニックMOR (CA) は,離脱性ハイパーアルゲシアを抑制することによって,急性から慢性疼痛への移行を防ぐことができます.
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