人間におけるアルファアドレナジック冠動脈静脈収縮および心筋力不全症
G Heusch1, D Baumgart, P Camici
1Abteilung für Pathophysiologie and Abteilung für Kardiologie, Universitätsklinikum Essen, Essen, Germany. gerd.heusch@uni-essen.de
Circulation
|February 15, 2000
まとめ
アルファアドレナジック冠動脈収縮は静止状態では存在しませんが,内皮機能不全や動脈硬化などの状態では増幅されます. この増幅された収縮は,心筋不全を引き起こし,心臓の機能を損なう可能性があります.
科学分野:
- 心臓病学 心臓病学
- 薬理学 薬理学とは
- 生理学 生理学とは
背景:
- アルファ・アドレナジック冠動脈血管運動は,心臓への血流の調節に不可欠です.
- 動物での以前の研究では,冠動脈におけるアルファ・アドレナゲン受容体の役割が示唆されていた.
研究 の 目的:
- 人間におけるアルファアドレナジック冠動脈動脈運動を調査するために.
- 冠動脈内皮機能不全および動脈硬化におけるアルファ-アドレノ受容体活性化の役割を決定する.
主な方法:
- 定量冠動脈動脈造影は,定量的な冠動脈造影によるものです.
- ドップラー測定によるドップラー測定
- ポジトロン放出トモグラフィー (PET)
主要な成果:
- ヒトでは,静止状態でのアルファアドレナージック冠動脈圧縮体トーンを示す証拠はありません.
- アルファ-アドレノ受容体の活性化により,内皮機能障害と動脈硬化症の存在において,冠動脈収縮が著しく増加した.
- エピカルディアの動脈とマイクロ血管のアルファ1−およびアルファ2−アドレノ受容体の両方が関わっていた.
- 運動や介入中に収縮が増加し,心筋不全や心機能低下に至った.
- 最近の発見は,アルファ (((2) - アドレナジック冠動脈収縮に対する遺伝的影響を示唆しています.
結論:
- アルファ・アドレナジック冠動脈収縮は休息時の要因ではなく,病理学的条件下で有意になる.
- 内皮機能不全と動脈硬化症は,アルファ-アドレナジック反応を高め,潜在的にイシュケミアを引き起こす可能性があります.
- アルファ・アドレナージック経路,特にアルファ2受容体を含む経路は,冠動脈疾患を理解し管理する上で重要な標的である.
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