オルソスタティック不耐性のヒトモデルとして,選択的ノルエピネフリン再吸収阻害
Christoph Schroeder1, Jens Tank, Michael Boschmann
1Clinical Research Center, HELIOS Klinkum-Berlin, Germany. jordan@fvk-berlin.de
Circulation
|January 24, 2002
まとめ
レボキセチンによるノレピネフリントランスポーター (NET) 機能のブロックは,健康な被験者のイディオパシー・オースタティック不耐性を模倣した. これは,ノレピネフリン吸収の低下が心血管疾患に寄与し,血管回路反応を予防するのに役立つことを示唆しています.
科学分野:
- 心血管生理学 心血管の生理学
- 神経薬理学神経薬理学について
背景:
- ノルエピネフリントランスポーター (NET) 遺伝子の機能性突然変異は,イディオパシー・オーソスタティック不耐性に関連しています.
- ノルエピネフリン再吸収の障害は,この状態に寄与する潜在的な要因です.
研究 の 目的:
- 健康な個体におけるノレピネフリントランスポーター (NET) の選択的阻害による心血管効果を調査する.
- NETブロックがイディオパシー・オーソスタティック不耐症のフェノタイプを複製するかどうかを判断する.
主な方法:
- 18人の健康な被験者を対象としたランダム化,ダブルブラインド,クロスオーバー研究.
- 選択的なNETブロッカー (レボセチン) またはプラセボの投与.
- コールドプレッサーテスト,ハンドグリップテスト,ヘッド・アップ・ティルト・テスト (HUT) の心臓血管反応の評価.
主要な成果:
- レボキセチンは,プラセボと比較して,HUT中に心拍数を有意に増加させた (P<0.0001).
- 平均動脈圧はレボキセチンでわずかに上昇しましたが,ストレステストに対する血圧の反応は弱まりました.
- レボキセチンは,イソプロテレノールとフェニルエフリンに対する感受性を高め,血管内反応を減少させた.
結論:
- 選択的なNET阻害は,イディオパシー・オーソスタティック不耐症に似た心血管現象型を誘発する.
- これは,ノルエピネフリン再吸収の乱れが人間の心血管疾患に寄与するという仮説を裏付けている.
- NET阻害は,血管関節反応を予防する潜在的な戦略である可能性があります.
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