慢性心不全における骨格筋の変化
Circulation
|May 1, 1992
まとめ
慢性心不全 (CHF) の患者の骨格筋は,ミトコンドリア密度と酸化能力の低下を示し,運動能力の低下に貢献します. これらの筋肉の変化は,効果的な治療で回復する可能性があります.
科学分野:
- 心臓病学 心臓病学
- 運動生理学 運動生理学
- 骨格筋の生物学について
背景:
- 慢性心不全 (CHF) は運動能力の低下と関連しています.
- 骨格筋の変化は,この制限に寄与すると疑われています.
研究 の 目的:
- CHF患者における骨格筋の異常の発生率と特徴を調査する.
- これらの筋肉の変化と運動能力との関係を決定する.
主な方法:
- 超構造形態測定は,57人のCHF患者と18人の対照群の骨格筋バイオプシを分析するために使用されました.
- ミトコンドリアの体積密度 (Vvm) と表層の表面密度 (Svmc) は酸化能力の指標として評価されました.
- 毛細血管密度と繊維の種類分布も評価した.
主要な成果:
- CHFの患者は,VvmとSvmcの約20%の減少を示し,酸化能力の低下を示した.
- 筋肉毛細血管の密度が低下し,II型繊維への移行がCHFで観察されました.
- Vvm と Svmc は,ピーク運動 VO2 と無酸素値 VO2 と強く相関していました.
- 一部の患者では,Vvmの変化は,時間の経過とともにピーク運動VO2の変化と相関していた.
結論:
- CHFの患者は,骨格筋の重要な超構造的異常を発症し,酸化能力を低下させます.
- これらの筋肉の変化は,CHFの運動能力の低下に貢献します.
- 観察された骨格筋の異常は,適切な治療で潜在的に可逆性があるようです.
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