ベータ1-アドレネルゲン受容体阻害は,ミトラルリグルジテーションにおける心臓のインタースティチウムへのアンジオテンシンII媒介のカテキオラミン放出を弱める
José Tallaj1, Chih-Chang Wei, Gerald H Hankes
1Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
Circulation
|July 9, 2003
まとめ
ベータ1-アドレノレセプター阻害は,ミトラルリグルジテーション犬の心臓のノルエピネフリンとエピネフリン放出を減少させます. この治療は,アンジオテンシンII媒介の共感刺激を弱め,早期の体積過負荷時に心臓のアンジオテンシン変換酵素の発現を低下させます.
科学分野:
- 心血管生理学 心血管の生理学
- 薬理学 薬理学とは
- 腎臓系 腎臓系 腎臓系
背景:
- ミトラル反発 (MR) は心臓機能不全につながる可能性があります.
- レニン-アニオテンシン系 (RAS) は,心血管の調節に役割を果たします.
- ベータ-1アドレネルゲン受容体は,交感神経系の活動に関与する.
研究 の 目的:
- ベータ1-アドレノレセプター阻害が心臓におけるアンジオテンシンII (Ang II) 誘発のノルエピネフリン (NE) とエピネフリン (Epi) の放出に影響するかどうかを調査する.
- ベータ1受容体阻害が心筋NEとEpiレベルに与える影響を,犬のミトラルリグルジテーションモデルで調べる.
主な方法:
- 実験的に誘発されたミトラル反吐 (MR) の犬のモデルが使用されました.
- MRの犬はベータ1受容体阻害剤 (メトプロロールサクシネート) で治療された.
- アンジオテンシンIIを注入して,NEとEpiが心臓の間位液 (ISF) と循環に放出されることを評価した.
主要な成果:
- プラズマAng II濃度はMR犬において有意に増加した.
- Ang II輸液は,MR犬のISFと循環中のNEとEpiを上昇させた.
- ベータ1受容体阻害により,MR犬のNEとEpiレベルが正常に回復し,心臓のアンジオテンシン変換酵素活性が低下した.
結論:
- ベータ1受容体阻害は,初期段階のMRにおけるRAS媒介の共感刺激を効果的に減少させます.
- この治療は,Ang II誘発のNEとEpiを心臓のISFと循環に放出することを弱める.
- ベータ1受容体阻害は,体積過負荷中に心血管新生素変換酵素の発現を低下させる.
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