人間の冠動脈と外周循環におけるL-アルギニン輸送
S E S Miner1, A Al-Hesayen, S Kelly
1Mount Sinai Hospital and University Health Network, University of Toronto, Ontario, Canada.
Circulation
|March 10, 2004
まとめ
この研究では,酸化窒素合成酵素 (NOS) の活性がプラズマのアルギニン濃度によって影響され,アセチルコリンはアルギニンの吸収を刺激し,N (((G)) -モノメチル-L-アルギニン (L-NMMA) は人間の冠動脈循環におけるアルギニンの流出を誘導する.
科学分野:
- 心血管生理学 心血管の生理学
- バイオケミストリー バイオケミストリー
- 医学研究 医学研究
背景:
- 酸化窒素合成酵素 (NOS) は,アルギニンから酸化窒素 (NO) を合成する.
- 細胞内アルギニンのレベルは,通常,NOSの活動がプラズマアルギニンとは独立していることを示唆します.
- しかし,プラズマアルギニンの増加は,NOS活動の増加と相関することがあります.
研究 の 目的:
- 人間の冠動脈および外周循環におけるアルギニン輸送を調査する.
- プラズマアルギニンとNOS活動との関係を理解するために.
主な方法:
- マスラベルの15N2-アルギニンの注入で31人の患者で安定状態に達した.
- 心臓キャセテリゼーションと冠動脈鼻腔カテーテル設置.
- 静止状態およびアセチルコリンおよびL-NMMA注入中のトランスカルディア15N2-アルギニングラデントの測定.
主要な成果:
- 静止状態ではアルギニン・グラデーションが検出されませんでした.
- アセチルコリン注入はアルギニンの有意なグラデーションを誘導し,NOS刺激がアルギニンの輸送 (11.7%の分量抽出) を強化することを示しています.
- L-NMMA注入は負のグラデントをもたらし,トランスポーター媒介型トランスシミュレーション (20.5%の分量生産) によるアルギニン流出を示唆した.
結論:
- 安定状態の15N2-アルギニンは,トランスオルガンのL-アルギニングラデントを研究するための新しいツールです.
- この方法は,L-アルギニンの輸送メカニズムを理解するのに役立ちます.
- それは,内皮およびNOS機能不全のメカニズムについての洞察を提供します.
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