系統的なティラミン投与中に逆説的な前腕血管拡張による神経血管解離
Giris Jacob1, Fernando Costa, Simi Vincent
1Jacob Recanati Autonomic Dysfunction Center, Department of Internal Medicine C, Rambam Medical Center, Haifa, Israel.
Circulation
|April 23, 2003
まとめ
系統的なチラミン注入はノレピネフリン放出を増加させるが,逆説的に前腕の血管拡張を引き起こすが,血管収縮ではない. これは,ティラミンの血管作用と交感神経の活動に関する以前の仮定に異議を唱える.
科学分野:
- 薬理学 薬理学とは
- 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.
背景:
- ティラミンは,交感神経からのノレピネフリン放出を研究するために使用されます.
- 血管への影響,特に全身性血管収縮は,十分に理解されていません.
- 以前の研究では,チラミンは最小限の全身血管収縮を引き起こすことを示唆しています.
研究 の 目的:
- 系統的なティラミン注入の血管効果を調査するために.
- 前腕の局所的なノレピネフリン溢出と血管抵抗に対するチラミンの影響を決定するために.
- ティラミンが同情神経からノレピネフリンを有意に放出しないという仮説を検証するために.
主な方法:
- 7人の健康な被験者を対象に,前腕の全身的および局所的なノレピネフリン流出と前腕の血流を測定した.
- 系統的にチラミンを注入し,冷圧器試験を通じて同情刺激を誘導した.
- チラミン投与中にさらに6人の被験者の血ドーパミン濃度を測定した.
主要な成果:
- ティラミン注入は,全身および前腕のノレピネフリン溢出を著しく増加させた.
- ティラミンによる前腕のノレピネフリン放出は,冷たいプレッサー刺激に匹敵していました.
- ティラミンは,前腕の血管拡張を引き起こし,冷たい圧力器のテスト中に血管収縮と対照的にしました.
- プラズマ・ドーパミンの濃度はチラミン投与で有意に増加した.
結論:
- 系統的なティラミン注入は,周辺のノレピネフリン溢出を大幅に増加させます.
- ノルエピネフリンの溢出量の増加は,逆説的に,局所的な前腕の血管拡張と関連しています.
- ティラミンの血管への影響は,ノレピネフリン放出に基づく期待とは異なる.
キーワード:
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