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ダイナミックな運動中に骨格筋への栄養血流の新たな再分配指数
1Second Department of Internal Medicine, Toyama Medical and Pharmaceutical University, Japan.
Circulation
|April 1, 1992
まとめ
この研究は,タリウム活性を用いた運動する足における血流の再分配を定量化するための方法を導入しています. 運動している足と休んでいる足の間のタリウム比は,運動中の血管トーンの変化を効果的に示している.
科学分野:
- 運動生理学 運動生理学
- 心血管生理学 心血管の生理学
- 核医学画像検査について
背景:
- 運動中に働く筋肉への心臓出力の再分配は極めて重要です.
- エルゴメーターまたはトレッドミルの運動中に大きな筋肉グループへの血流の分布を定量化することは困難でした.
研究 の 目的:
- 運動中に働く筋肉への血流の再分配を定量化するための方法を開発し,検証する.
- 運動する四肢における血管抵抗と血流の地域的変化を評価する.
主な方法:
- タリウム-201 (Tl-201) スシンチグラフィーを使って,運動しているときと休息しているときに,地域の放射能を測定しました.
- 10人の健康な被験者のペダルを踏む足のタリウム活性と,反対側の休息する足のタリウム活性を比較した.
- 静止状態のタリウム分布,無酸素値,片足サイクリング中のピーク運動を測定した.
主要な成果:
- タリウムの活動は,運動している大腿と小腿で,無酸素の値とピーク運動で有意に増加しました.
- タリウム活性の大幅な減少は,運動していない小牛で観察されました.
- 運動している足と運動していない足の間のタリウム活動比は,血流の再分配を反映して,実質的に増加しました.
結論:
- 血流の再分配は,主に軽度から中等度の運動中に起こります.
- 運動している足と運動していない足の間のタリウム活動比は,血管トーン差異と血流再分配の非侵襲的定量指数として機能します.
- 激しい運動中に,脚の血流は主に心臓の出力量の増加によって影響されます.
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