短期的な心房細動後の心房収縮機能不全はヴェラパミルによって減少するが,BAY K8644によって増加する
E Leistad1, G Aksnes, E Verburg
1Institute for Experimental Medical Research, University of Oslo, Ullevål Hospital, Norway. elizabeth.leistad@ioks.uio.no
Circulation
|May 1, 1996
まとめ
カルシウムチャネルブロッカーのヴェラパミルは,心房動後の心房収縮機能不全を軽減し,カルシウム流入がこの状態に寄与することを示唆しています. カルシウムアゴニストのBAY K8644は機能不全を悪化させた.
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:
- 動脈動停止後,心房の収縮性は低下する.
- この発作後の心房機能不全のメカニズムは不明である.
- 急速な脱極化による細胞内カルシウム過負荷は,仮説的な原因である.
研究 の 目的:
- 脈動後心房機能不全におけるトランスサルコレマカルシウム流入の役割を調査する.
- この機能障害に対するカルシウムチャネルブロッカーおよびアゴニストの効果を調べる.
- 観察された機能不全に心房不全が寄与しているかどうかを判断する.
主な方法:
- 誘発性心房細動を患った開いた胸の豚を研究した.
- 心房収縮性は,左心房直径の縮小によって測定されました.
- ベラパミル (カルシウムアゴニスト) またはBAY K8644 (カルシウムアゴニスト) は,第2回動期前に投与されました.
主要な成果:
- ベラパミルは,発作後の心房収縮機能不全の程度と期間を低下させた.
- BAY K8644 発作後の心房収縮機能不全が増加した.
- クレアチンフォスファートの心房組織レベルはわずかに低下し,ATPと乳酸は変化せず,有意な不血症を示さなかった.
結論:
- トランスサルコレムカルシウム流入は,心房細動後の心房収縮機能不全に寄与する.
- カルシウムチャネルアンタゴニズム (ヴェラパミル) は,この機能障害を緩和します.
- カルシウムチャネルアゴニズム (BAY K8644) は,動後の心房収縮機能不全を悪化させる.
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