まとめ
ヨウ素濃縮コントラストメディアを用いた冠動脈動脈撮影は,ヒトにおける反射前腕血管拡張を誘発する. 冠動脈受容体によって媒介されるこの効果は,アトロピンによって遮断され,神経経路を示唆しています.
科学分野:
- 心血管生理学 心血管の生理学
- 放射線学 放射線学
背景:
- 冠動脈動脈撮影は,一般的な診断手順です.
- 冠動脈血管撮影中のコントラスト媒体の周周周血管効果は完全に理解されていません.
研究 の 目的:
- 冠動脈動脈撮影の反射的外周血管効果を調査するために.
- コロナリア動脈受容体のコントラスト誘発性血管拡張における役割を決定する.
主な方法:
- 前腕の血流は,プレチスモグラフィを用いて測定した.
- 前腕の血管抵抗は,冠動脈動脈造影術の前およびその間に計算されました.
- コントラストメディア (Hypaque-M,Renografin-76) を左冠動脈と昇動動脈に注入した.
- アトロピンは,血管拡張に対する効果を評価するために投与されました.
主要な成果:
- Hypaque-Mの冠内注射は,前腕の大幅な血管拡張 (83.4%の血流増加,44.4%の抵抗低下) を引き起こしました.
- レノグラフィン-76は,血管拡張が顕著でない (21%の血流増加,32%の抵抗低下) 状態をもたらした.
- 大動脈へのコントラスト注射は,同様の血管拡張を引き起こさなかったが,アトロピンはその効果を阻害した.
結論:
- 冠内コントラストメディアは,心筋や冠動脈の受容体を活性化させることができます.
- この活性化は,ヒトの被験者における反射的な前腕血管拡張につながります.
- 血管拡張は,アトロピンに敏感な神経経路によって媒介されるようです.
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