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ヒトのマイクロ血管内皮細胞における組織因子の発現を酸化窒素によって調節する
1Whitaker Cardiovascular Institute and Evans Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA.
Circulation
|May 10, 2000
まとめ
内皮から派生した酸化窒素 (NO) は,内皮細胞における組織因子 (TF) の発現と活性を著しく抑制する. この発見は,NOがこれらの細胞のプロトロンボティック現象型を減らす上で重要な役割を果たしていることを示唆しています.
科学分野:
- 血管生物学 血管生物学
- 内皮細胞の機能
- トロンボシスと血液静止症
背景:
- 組織因子 (TF) は,血液静止およびアテロトロンボティック疾患におけるトロンビン生成に不可欠です.
- 内皮に由来する酸化窒素 (NO) は,抗血栓性および抗動脈硬化性を持つ.
- TF発現におけるNOの規制的役割は未検討のままである.
研究 の 目的:
- TF発現と活性に対する内生性エンドセリウム由来NOの影響を調査する.
- NOが炎症刺激によるTF誘導を調節するかどうかを判断する.
主な方法:
- 人間のマイクロ血管内皮細胞は,TFを誘発するために,リポポリサッカリド (LPS) またはインタールイキン-1β (IL-1β) で刺激されました.
- TF活動,タンパク質,mRNAレベルを測定した.
- 抑制効果を評価するためにL-アルギニン (NO前駆体) を加え,D-アルギニンとNO合成酵素阻害をコントロールとして使用した.
主要な成果:
- LPSとIL-1βの投与量と時間により,TFの活性と発現が増加した.
- L-アルギニンは24時間後にTF活性誘導を著しく抑制しました (LPSの66%,IL-1βの59%).
- TFタンパク質とmRNA濃度の低下と相関するTF活性抑制;D-アルギニンとNO合成酵素の抑制は効果がなかった.
結論:
- エンドセリウム由来NOの増産は,エンドトキシンおよびサイトカイン誘発のTF発現を減少させます.
- NOは,内皮細胞のプロトロンボティック現象型を減少させます.
- これらの発見は,NOを媒介する血管保護のための新しいメカニズムを強調しています.
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