バロレフレクスのバッファリングは,健康な男性では年齢とともに減少します
Pamela Parker Jones1, Demetra D Christou, Jens Jordan
1Department of Kinesiology and Applied Physiology, University of Colorado at Boulder, UCB 354, Boulder, CO 80309, USA. pamela@spot.colorado.edu
Circulation
|April 1, 2003
まとめ
健康的な老化は,男性におけるバロレフレクスのバッファリングを大幅に減らし,血圧制御に影響を与えます. この減少は,交感神経の活動の増加と血管の応答性の低下に関連しています.
科学分野:
- 心血管生理学 心血管の生理学
- 自律神経系の機能 自律神経系の機能
- ヒトの老化に関する研究
背景:
- バロレフレクスのバッファリングは,動脈血圧のホメオスタシスの維持に不可欠です.
- 健康で生理的な老化がヒトのトニック・バロ・レフレクスのバッファリングに与える影響は,依然としてほとんど不明である.
研究 の 目的:
- 男性のバロレフレクスのバッファリングに健康的な老化の影響を調査する.
- 老化,バロレフレクスのバッファリング,共感神経の活動との関係を調査する.
主な方法:
- 若年 (25歳) と高齢者 (65歳) の健康な男性におけるバロレフレクスのバッファリングの評価.
- ガングリオン阻害 (トリメタファン) の前およびその間,フェニルエフリンに対するシストリック血圧の反応を測定した.
- シストリック血圧応答 (BRBbolusとBRBslope) の強化によるバロレフレクスのバッファリングの評価.
主要な成果:
- 年配の男性は,若い男性と比較して,バロレフレクスのバッファリング (BRBbolusとBRBslope) が著しく減少した.
- 高齢の男性におけるバロレフレクスのバッファリングの減少は,筋肉の交感神経活動の増加と相関していた.
- バロレフレクスのバッファリングは,フェニレフリンに対するシストリック血圧の反応と反転的に関係していました.
結論:
- 男性の生理学的老化は,バロレフレクスのバッファリングの大幅な減少と関連しています.
- この減少は,基礎交感神経の活性が上昇し,アルファ1-アドレナジック血管の反応性が低下している.
- この発見は,心血管疾患を含む高齢者のバロレフレクスの変化を理解するのに役立ちます.
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