ガドリニウムは,ストレッチによる心房細動に対する脆弱性を低下させます
F Bode1, A Katchman, R L Woosley
1Department of Pharmacology, Georgetown University, Veterans Affairs Medical Center, Washington, DC 20422, USA.
Circulation
|May 10, 2000
まとめ
心房のストレッチは心房細動 (AF) のリスクを高めます. ガドリニウム (Gd3+) でストレッチ活性化チャネル (SAC) を遮断すると,この脆弱性が著しく低下し,AFに対する新しい抗不律性戦略を示唆します.
科学分野:
- 心臓病学 心臓病学
- 電気生理学 電気生理学
- 薬理学 薬理学とは
背景:
- 心房細動 (AF) は,圧力/体積過負荷による心房拡大と関連しています.
- 伸縮活性化チャネル (SAC) は,心筋細胞に存在し,大心房の拡張でAFに寄与する可能性があります.
研究 の 目的:
- SACブロッカーガドリニウム (Gd3+) が,隔離されたウサギの心臓における心房伸縮時のAF傾向に及ぼす影響を調査する.
主な方法:
- 孤立したランゲンドルフ浸透したウサギの心臓を使用した.
- 心房圧が上昇し,AFの脆弱性は,バーストペースで評価されました.
- ガドリニウム (Gd3+) は増加量 (12.5,25,50 μmol/L) で投与された.
主要な成果:
- AF誘導には,Gd3+投与後,心房圧が著しく上昇することが必要であった (19.0±0.5cmのH2Oと50μmol/LのGd3+対8.8±0.2cmのH2Oベースライン).
- Gd3+は,投与量に依存してAFの脆弱性を軽減し,自発的なAF走行を予防しました.
- Gd3+は,心房有効耐火期に有意な影響を及ぼさなかった.
結論:
- 急性心房伸縮はAFの脆弱性を高めます.
- ガドリニウム (Gd3+) は,ストレッチによるAFの脆弱性を,投与量に依存した方法で効果的に軽減します.
- SACsを遮断することは,心房の圧力または体積の上昇に関連したAFに対する新しい抗不律的アプローチを提供することができます.
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