エピネフリンは,フェニレタノアラミンN-メチルトランスフェラーゼのノックアウトマウスのストレスに対する正常な心血管反応に必要なものです
Xuping Bao1, Chuanyi M Lu, Fujun Liu
1Department of Medicine, University of California San Diego, USA. xbao@ucsd.edu
Circulation
|August 19, 2007
まとめ
エピネフリンは,ストレス中の正常な血圧と心臓の充填に不可欠ですが,ストレス中の静止心血管機能や心拍数上昇には欠かせません. この研究では,エピネフリンの役割を調査するためにマウスモデルを使用しました.
科学分野:
- 心血管生理学 心血管の生理学
- 内分泌学 エンドックリノロジー
- 神経科学は神経科学である.
背景:
- エピネフリン (EPI) は重要な神経伝達物質とホルモンです.
- 休息とストレス中の心臓血管の調節におけるその正確な役割は,まだ完全に理解されていません.
研究 の 目的:
- 静止状態および生理学的ストレス中の心血管調節におけるエピネフリンの役割を調査する.
- 血圧,心拍数,心拍出力の調節におけるエピネフリンの特定の機能を明らかにする.
主な方法:
- フェニレタノラミンN-メチルトランスフェラーゼ (PNMT) 遺伝子をノックアウトすることによって,エピネフリンに欠陥のあるマウスモデルを生成しました.
- 心血管のパラメータ (血圧,心拍数) をテレメトリで,休息状態や運動中の状態でモニターする.
- 様々な生理学的条件下でエコーカルディオグラフィーを用いて心臓の構造と機能を評価した.
主要な成果:
- エピネフリン不足のマウスは,正常な休息時の心血管機能とノレピネフリン濃度を示した.
- 同情的抑制と運動中にノックアウトマウスで血管拡張の障害が観察されました.
- 心臓の改造,特に左心房の後部壁の厚さの増加は,縮なしに観察されました.
- 終結ダイアストリック容量の減少による心電量減少は,覚醒状態でストレスを受けたノックアウトマウスで発生しました.
結論:
- エピネフリンは,ストレス中に正常な血圧と心臓の充填反応を維持するために不可欠です.
- エピネフリンは,ストレスに対する心拍数応答 (心拍動脈) に必要ありません.
- 静止状態の正常な心血管機能は,エピネフリンに依存していないようです.
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