ポストコンディショニングは,ミトコンドリアの透過性移行を阻害する
Laurent Argaud1, Odile Gateau-Roesch, Olivier Raisky
1INSERM E 0226, Université Claude Bernard Lyon I, France.
Circulation
|January 12, 2005
まとめ
リパーフュージョン中の短い介入であるポストコンディショニングは,ミトコンドリアの透過性移行孔 (mPTP) を阻害することにより,心臓発作のサイズを大幅に減らす. この保護効果は強力な抗イシュケミア効果をもたらします.
科学分野:
- 心血管研究 循環器科の研究
- ミトコンドリア生物学
- 発血不全性損傷 発血不全性損傷とは
背景:
- リパーフュージョン中の短期的な缺血は,ポストコンディショニングとして知られており,心臓発作のサイズを制限することができます.
- ミトコンドリアの浸透性トランジション孔 (mPTP) の開口は,致命的な再注射損傷に関与しています.
- この研究では,ポストコンディショニングがmPTPの開通に影響するかどうかを調査した.
研究 の 目的:
- ポストコンディショニングがミトコンドリアの透過性移行孔 (mPTP) の開口を調節するかどうかを判断する.
- ischemia-reperfusion injuryに対するポストコンディショニングの保護効果を評価する.
主な方法:
- 胸を開けたウサギは30分間の不血症と4時間の再注血を受けた.
- ポストコンディショニングは,初期リフロー後,短期のイシュケミアと再注血のサイクルを伴う.
- ミトコンドリアCa2+誘発のmPTPの開口と心臓発作の大きさを測定した.
主要な成果:
- ポストコンディショニング,プリコンディショニング,mPTP阻害剤NIM811により,対照群と比較して心臓発作のサイズが著しく減少しました (29%, 18%, 20% vs. 61%).
- mPTPを開くために必要なCa2+負荷は,後条件,前条件,およびNIM811で治療されたグループ (41, 47, 67 μmol/L CaCl2/mg) と対照群 (16 μmol/L CaCl2/mg) で著しく高かった.
結論:
- ポストコンディショニングは,ミトコンドリアの透過性移行孔 (mPTP) の開口を効果的に阻害します.
- この阻害は,心臓発作の大きさを減らす,有意な抗血動性保護を与える.
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