ベータブロッカーの自由根誘発性心筋収縮機能不全に対する効果
1Klinik III für Innere Medizin and Klinik für Herz- und Thoraxchirurgie (M.S.) der Universität zu Köln, Cologne, Germany.
Circulation
|July 27, 1999
まとめ
ヒドロキシルラジカルは,SERCAの活性を抑制することによって,人間の心臓筋の収縮とリラックスを損なう. カーベディロールとその代謝物質BM-910228は,このヒドロキシルラジカルによって引き起こされる機能障害に対して部分的に保護されています.
科学分野:
- 心臓病学 心臓病学
- バイオケミストリー バイオケミストリー
- 薬理学 薬理学とは
背景:
- ヒドロキシル基 (OH) は, 心血管損傷に関与している.
- ベータ受容体アンタゴニストは,心臓病の治療に使用されます.
研究 の 目的:
- ヒドロキシルラジカルがヒトの心筋収縮性とSERCA活動に及ぼす影響を調査する.
- メトプロロール,カルベディロール,およびその代謝物質BM-910228の,ヒドロキシルラジカルによるダメージに対する保護効果を評価する.
主な方法:
- 孤立したヒト心筋膜は,収縮の同位数的な力を評価するために使用されました.
- サルコプラズマ網膜のCa(2+) -ATPase (SERCA) 活性は,心筋膜製剤で測定されました.
- ヒドロキシルラジカルとベータ受容体アンタゴニストの効果が検討されました.
主要な成果:
- ヒドロキシルラジカルは基礎収縮力を減らし,腹動脈の緊張を増加させた.
- ヒドロキシルラジカルは,カルシウムに対するイノトロピック反応を低下させ,力-周波数関係を廃止した.
- カーベディロールとBM-910228は,ヒドロキシルラジカルに誘発された収縮機能不全を弱め,SERCA活性を維持したが,メトプロロールは有意な効果を示さなかった.
結論:
- ヒドロキシルラジカルは,SERCAを阻害することによって,ヒトの心筋収縮,リラックス,および力-周波数関係を損なう.
- カーベディロールおよびその代謝物質BM-910228は,ヒドロキシルラジカルによって引き起こされる心臓機能不全に対して部分的な保護を提供します.
- これらの発見は,ベータアドレネルゲン受容体の密度に影響を与えることなく,心不全におけるカルベディロールの効果を説明する可能性がある.
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