フォース-周波数関係のアドレネージック制御

J Ross¹, T Miura, M Kambayashi

¹Department of Medicine, University of California, San Diego, La Jolla 92093-0613, USA.

Circulation

|October 15, 1995

まとめ

ベータアドレネルジック受容体刺激は,力-周波数関係を通して心筋収縮性を高めます. 心臓の機能に不可欠なこの効果は,心不全で損なわれます.

科学分野:

心臓病学心臓病学
生理学生理学とは

背景:

フォース-周波数関係は,心拍数とともに心筋収縮性がどのように増加するかを説明します.
ベータアドレネルジック受容体の刺激は,心臓の収縮性に影響を与えます.

研究の目的:

ベータアドレナジック刺激が力-周波数関係に及ぼす影響に関する実験的研究をレビューする.
フォース・周波数関係におけるベータ・アドレナジック増幅の段階的メカニズムを探求する.
このメカニズムが正常な心と衰弱した心における役割を調査する.

主な方法:

最近の実験研究のレビュー.
変化する心拍数とβ-アドレネルジック刺激の下での心筋収縮性の分析.
シストリックとダイアストリックの心室機能の評価.

主要な成果:

ベータアドレネルジック刺激は,力-周波数関係を大幅に高め,心筋収縮性を高めます.
この増幅は,運動やベータアドレナジックアゴニストで顕著です.
腎上腺増幅の障害は,実験的な心不全モデルで観察されています.

結論:

フォース・周波数関係のベータ・アドレナージック増幅は,心臓のイノトロピック状態を制御するための重要な内在的なメカニズムです.
このメカニズムは,運動のような生理学的ストレス中に心臓の機能に不可欠です.
この増幅の欠陥は,心不全における心機能障害に寄与する可能性があります.

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