ギャップ・ジャンクション・ブロッカーは,隔離されたウサギの心臓における心室屈折率の変化なしに除細動の値を下げる
1Department of Medicine, St Michael's Hospital, University of Toronto, Toronto, Ont, Canada.
Circulation
|September 26, 2001
まとめ
16-DSAと1-ヘプタノールのようなギャップ・ジャンクション・ブロッカーは,除細動の値 (DFT) と心房細動のサイクル長 (VFCL) の分散を著しく低下させます. 対照的に,リドカインは,伝導速度に同様の効果があるにもかかわらず,DFTを増加させます.
科学分野:
- 心血管電気生理学 心血管電気生理学
- 薬理学 薬理学とは
- 医学物理 医学物理学
背景:
- リエントリー不律症は,屈折性や伝導速度などの組織特性に依存する.
- 電気生理学と除細動値 (DFT) に対するNa(+) とK(+) チャンネルブロッカーの影響は知られていますが,ギャップジャンクションブロッカーの効果はあまり理解されていません.
研究 の 目的:
- 隔離されたウサギの心臓における除細動値 (DFT) と電気生理学的特性に対するギャップ・ジャンクション・ブロッカー (16-ドキシルステアリック酸と1-ヘプタノール) とナトリウム・チャネル・ブロッカー (リドカイン) の影響を調査する.
主な方法:
- 16ドキシルステアリック酸 (16-DSA),1ヘプタノール,またはリドカインを隔離された浸透されたウサギの心臓に投与する前に,および投与後に,除細動値 (DFT) を測定した.
- 静脈動のサイクル長 (VFCL),QRSの持続時間,静脈動の有効耐火期を含む電気生理学的パラメータが評価されました.
主要な成果:
- 16-DSAと1-heptanolは,それぞれ23%と21%のDFTを大幅に減少させました. リドカインはDFTを26%増加させた.
- すべての薬剤はVFCLとQRSの持続時間を増加させ,VFCLの分散を減少させた. 屈折性はギャップ・ジャンクション・ブロッカーによって変化しなかったが,リドカインで増加した.
- コントロールハートは,DFTまたは電気生理学的変数の有意な変化を示さなかった.
結論:
- 16-DSAと1-ヘプタノールによる電気解離は,反射性に影響を与えることなく,DFTとVFCLの分散を減少させます.
- リドカインは,同様に伝導を遅らせながら,DFTを増加させ,心臓の電気的安定性に対するチャネルブロッカーの差異的な効果を強調します.
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