筋のα1-アドレネルゲン受容体刺激とブロックがヒトの収縮性に与える影響
J S Landzberg1, J D Parker, D F Gauthier
1Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115.
Circulation
|October 1, 1991
まとめ
ヒトにおける心筋アルファアドレネルゲン受容体の刺激は,陽性な内otropic効果を引き起こすが,基礎収縮性には影響しない. この効果は,心不全の患者では減少する.
科学分野:
- 心臓病学 心臓病学
- 薬理学 薬理学とは
背景:
- アルファアドレネルゲン受容体は,人間の心臓筋に存在します.
- 人間の心臓の収縮性におけるそれらの役割は完全に理解されていません.
- これらの受容体は,他の種において陽性なイノトロプ効果を媒介する.
研究 の 目的:
- アルファ・アドレナゲン受容体刺激がヒトの左心房の収縮性に影響するかどうかを in vivo で判定する.
- これらの受容体が基礎収縮状態に寄与するかどうかを調査する.
主な方法:
- アルファアドレナジック剤 (フェントアミン,フェニルエフリン) を左側主冠動脈に注入する.
- 研究には,正常な左心室機能と心不全の患者が含まれていました.
- 左心室の収縮性は,ピークポジティブ dP/dt.を測定することによって評価される.
主要な成果:
- フェニルエフリンは,正常な心室と故障している心室の両方で,濃度に関連する陽性イノトロプ効果を引き起こしました.
- アルファ・アドレナジック効果は,心不全の患者で著しく弱まった.
- フェントオラミンは単独では左心房の収縮性を変化させなかった.
結論:
- 心筋のアルファアドレナージック受容体は,ヒトの基礎左心室の収縮性を維持しない.
- これらの受容体の刺激は,陽性なイノトロピー効果を生成する.
- この効果の大きさは,心不全では減少することがあります.
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