心不全患者の骨格筋反射:水素の役割
Adam C Scott1, Roland Wensel, Constantinos H Davos
1National Heart and Lung Institute, and Royal Brompton Hospital, Imperial College School of Science, Technology and Medicine, London, United Kingdom.
Circulation
|January 23, 2003
まとめ
筋肉の酸性 (H+) の増加は,慢性心不全 (CHF) のエルゴレセプタを過度に活性化させ,運動不耐性を引き起こす. 炭酸水素ナトリウム注入は,H+を減少させ,エルゴレセプター活動を正常化させ,H+が重要な役割を果たしていることを示唆しています.
科学分野:
- 心臓病学 心臓病学
- 運動生理学 運動生理学
- 骨格筋の生理学 骨格筋の生理学
背景:
- 骨格筋のエルゴレセプターは,慢性心不全 (CHF) の運動不耐性に関与しています.
- これらの受容体の過剰活性化は,筋肉作業の代謝副産物による刺激の増加に起因する可能性があります.
研究 の 目的:
- CHFにおけるエルゴレフレクスの過剰活性化におけるH+,K+,乳酸,および外周血液動力学の役割を調査する.
- これらの要因を調節することで,エルゴレフレクスの活動を正常化できるかどうかを判断する.
主な方法:
- 10人のCHF患者と10人の健康な対照群を研究した.
- ハンドグリップ後の地域循環器閉塞 (PH-RCO) を使用して,換気に対するエルゴレフレクスの寄与を評価.
- 選択注入 (インスリン,ナトリウムニトロプルシド,二酸化ナトリウム,ドーパミン,塩水) とグルコースフリーダイエットを行い,H+,K+,グルコース,乳酸塩の筋肉流液濃度を測定した.
主要な成果:
- CHFの患者は,塩水注入中に換気に対するエルゴレフレクスの効果を示した (対照群では6.7+/-2.3L/分,対照群では -0.1+/-0.5L/分,P<0.01).
- 炭酸ナトリウム注入は,エルゴレフレクスの活動を著しく低下させました (0.4+/-0.3L/分対対照群では -0.2+/-0.4L/分,P=NS;対塩水P<0.05).
- また,炭酸ナトリウムは運動中に筋肉のH+濃度を低下させました (47.4+/-1.3 vs. 50.0+/-1.4 nmol/L,P<0.05).
結論:
- 炭酸ナトリウム注入によるH+濃度の低下は,CHFにおけるエルゴレセプター活性増加を廃止した.
- これらの発見は,慢性心不全において,直接または間接的に,エルゴレフレクスの活性化におけるH+の有意な役割を示唆しています.
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