短期性イシュケミアの影響: 麻酔,予備条件付け,およびその臨床的影響: 第1部
1Heart Institute, Good Samaritan Hospital, Keck School of Medicine, University of Southern California, Los Angeles, CA 90017, USA. rkloner@goodsam.org
Circulation
|December 12, 2001
まとめ
短期のイシュケミアは,麻酔を介して心臓に害を与え,長期的な機能障害を引き起こす可能性があります. しかし,また,不血性予備条件を介して心臓を保護し,その後のイベントからの損傷を軽減します.
科学分野:
- 心血管生理学 心血管の生理学
- 心筋筋病理生理学 心筋筋病理生理学
背景:
- 犬における短時間の冠動脈閉塞 (最大15分) は,可逆的な筋細胞損傷を引き起こします.
- 発血不全は,発血後長期にわたる収縮機能不全によって特徴づけられる,麻痺した心筋を含む心筋の変化を誘発します.
- 麻痺は酸素の急性,カルシウムホメオスタシスの変化,および潜在的に収縮性タンパク質の変化と関連しています.
研究 の 目的:
- 短時間の血栓不全が心筋機能に及ぼす二重効果を探求する.
- 心筋麻痺と不血性予備条件付けのメカニズムと臨床的関連性を調査する.
主な方法:
- 冠動脈閉塞と再注血を含む犬での実験研究.
- 心筋麻痺に関連する臨床シナリオの観察.
- 酸素ラジカルスキャベンジャーとカルシウムチャネルブロッカーに関する実験データと臨床データのレビュー.
主要な成果:
- 短時間のイシュケミア (5〜15分) は,可逆的な損傷につながるだけでなく,麻痺した心筋を誘発する可能性があります.
- 麻痺した心筋は,長時間収縮機能不全を示す.
- 短期の不血症エピソードに続く再注射による不血症の予備条件付けは,死滅を減らすことによって,心臓を後に続くより長い閉塞から保護します.
結論:
- 短期性イシュケミアにはパラドックスな効果があります:心筋麻痺 (ネガティブ) と心筋不全の予備条件付け (保護性).
- そのメカニズムは,酸素ラジカル,カルシウムホメオスタシス,そして複雑な第2メッセージング経路を含む.
- 将来の研究は,麻痺を最小限に抑え,臨床的利益のための予備条件を最大限にすることを目指しています.
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