カリウムチャネル開拓剤の抗リズム効果は,遅れた再極化に関連するリズム異常に起因する
L Carlsson1, C Abrahamsson, L Drews
1Department of Cardiovascular Pharmacology, Astra Hässle AB, Mölndal, Sweden.
Circulation
|April 1, 1992
まとめ
カリウムチャネル開き薬ピナシジルおよびその類似品であるP1075およびP1188は,ウサギにおける薬剤誘発の多型心室タキアリズム (PVTs) を減少させた. これらの化合物はまた,早期のデポラライゼーション後を廃止し,活性化を誘発し,特定の心律不整症の治療の可能性を示唆しました.
科学分野:
- 心血管薬理学について
- 電気生理学 電気生理学
- イオンチャネルモジュレーション
背景:
- 再偏極化を遅らせる薬は,多形心室性タキアリズム (PVTs) を誘発し,トーサード・ド・ポインテスの1種である.
- PVTに対するカリウムチャネルオープナーの抗不律性潜在性は,調査が必要です.
研究 の 目的:
- クロフィリウム誘発のPVTsに対するピナシジルおよびそのピリジルシアノグアニジン類 (P1075,P1188) の抗リズム効果を評価する.
- これらの化合物が早期脱極化後 (EADs) に及ぼす影響と,心臓電気生理学におけるトリガーされた活動について調査する.
主な方法:
- クロフィリウムとメトキサミンを用いてPVTsを誘発したウサギの体内試験で,ピナシジル,P1075またはP1188.8の前処理を行った.
- ウサギのプルキンジェ繊維と心室筋細胞からのin vitro電気生理学的記録は,アクションポテンシャルの持続時間,EADs,およびトリガーされた活動を評価するために使用されます.
- グリベンクラミドによる薬理学的封鎖で,ATPに敏感なカリウムチャネルの役割を調査する.
主要な成果:
- ピナシジル,P1075,P1188は,用量に依存して,クロフィリウム誘発のPVTsの発生率を低下させた.
- P1075とP1188は,PVTsを完全に防ぐ高用量で,重要な抗不律効果を示した.
- In vitroでは,P1075は,クロフィリウム誘発のEADを廃止し,プルキンジェ繊維の活性化を誘発し,グリベンクラミドによって逆転した.
- ディルチアゼムは,ピリジルシアノグアニジンとは異なり,PVTの発生を弱めたわけではない.
結論:
- ATP感受性のカリウムチャネル活性化剤は,PVTsの予防と治療において有望であることが示されています.
- これらの発見は,リポラライゼーション異常に関連した不律律の管理におけるピリジルシアノグアニジンの治療的役割を示唆しています.
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