運動中にプラゾシンによるアルファアドレナージックブロックが,大径の冠動脈に及ぼす影響
Circulation
|March 1, 1992
まとめ
アルファ-1アドレネルゲン活性が,運動中に大動脈と小動脈の両方の拡張を制限する. これらのメカニズムをブロックすると,さらに血流と動脈の直径を向上させ,心臓の機能を改善します.
科学分野:
- 心血管生理学 心血管の生理学
- 運動生理学 運動生理学
- 薬理学 薬理学とは
背景:
- アルファ・アドレナージックメカニズムは,小型の冠動脈抵抗血管における運動誘発の膨張を制限することが知られている.
- 運動中の大動脈にアルファアドレナジックメカニズムが与える影響は,まだ研究されていない.
研究 の 目的:
- 運動中の大きな冠動脈直径にアルファアドレナジックメカニズムの影響を決定する.
- アルファ-1 アドレナージックブロックが,身体的運動中に冠動脈の膨張に影響するかどうかを調査する.
主な方法:
- ソノミクロメトリーは,トレッドミルの運動中に装置付き犬の円周動脈動脈直径を測定するために使用されました.
- アルファ-1 アドレナージックブロックは,プラゾシンを冠内注入することで達成された.
- プラゾシン投与前後に冠動脈血管抵抗と動脈直径を評価した.
主要な成果:
- 運動は円周動脈の血管拡張を誘発し,冠動脈の血管抵抗を低下させた.
- プラゾシンによるアルファ-1アドレナージック阻害は,冠動脈血管抵抗のさらなる低下と円周動脈冠動脈直径の有意な増加をもたらしました.
- プラゾシンなしの車体注入は,冠動脈血管抵抗または直径を変化させず,プラゾシンの特異的な効果を確認しました.
結論:
- 運動中のアルファ-1アドレネルゲン活性が,大動脈と小動脈抵抗血管の両方の拡張を制限する.
- アルファ-1アドレネルゲン受容体を遮断すると,運動による冠動脈血管拡張が強化されます.
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