感受組織イシュケミア:カプサイシン受容体のもう一つの新しい機能?
1Department of Anesthesiology, H187, Pennsylvania State University College of Medicine, and the Milton S. Hershey Medical Center, 500 University Dr, Hershey, PA 17033-0850, USA. hpan@psu.edu
Circulation
|September 15, 2004
まとめ
心臓感覚神経のヴァニロイド受容体-1 (VR1) は,心筋不全を検知する. VR1をアンタゴニストでブロックすると,不血症およびブラジキニンの投与中に神経の活性化が著しく低下します.
科学分野:
- 心血管生理学 心血管の生理学
- 神経科学は神経科学である.
- 痛みのシグナリング 痛みシグナリング
背景:
- 胸の痛みは心筋不全症の重要な症状ですが,そのシグナル伝達経路は不明です.
- バニロイド受容体-1 (VR1) は,心臓の感覚神経末端にある,知覚神経細胞のカチオンチャンネルです.
- 発血中の心臓神経の活性化におけるVR1の役割が調査されました.
研究 の 目的:
- 筋動脈不全時の心臓脊髄アフェレント神経の活性化におけるヴァニロイド受容体-1 (VR1) の役割を決定する.
主な方法:
- 麻酔状態のフェレットにおける心筋アファレントの単一単位活動の記録.
- 誘発された地域性心筋動脈不全症および適用されたブラジキニン.
- VR1抗体 (イオドレシニフェラトキシン) とブロッカー (ルテニウムレッド) を投与し,その効果がアフェレンスの神経活動に及ぼす影響を評価した.
主要な成果:
- 心臓アファレントは,心筋不全とブラジキニンに反応した.
- イオドレシニフェラトキシンは,イシュケミアとブラジキニンの両方に対するアファレント応答を著しく弱めた.
- ルテニウムレッドは,アフェレント応答に同様の抑制効果を示した.
結論:
- VR1が心臓脊髄アフェラント神経の缺血刺激を媒介するという最初の機能的証拠を提供する.
- VR1は,心臓の感覚神経の組織イシュケミアの分子センサーとして働き,心臓の nociceptorsを活性化することを示唆しています.
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