人間の心不全におけるパラドックス的な交感性筋肉反射活性化
Philip J Millar1, Hisayoshi Murai1, John S Floras2
1From the University Health Network and Mount Sinai Hospital Division of Cardiology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
Circulation
|December 4, 2014
まとめ
減少放出分数 (HFrEF) の心不全では,増加した充填圧は,逆説的に,健康な個体とは異なり,明確な単一ユニット応答を通じて,筋肉の交感神経の活動を刺激します.
科学分野:
- 心血管生理学 心血管の生理学
- 神経科学は神経科学である.
背景:
- 筋肉の交感神経活動 (MSNA) は,心不全の低射出分数 (HFrEF) で上昇します.
- これはしばしば,心肺機構受容体からの抑制フィードバックの減少に起因する.
- しかし,メカニカル受容体フィードバックには,対極的な反応を持つ異なる単一の単位集団が含まれます.
研究 の 目的:
- HFrEF.で充填圧が増加するにつれて,矛盾的に発火する単一のユニットの比率が増加するかどうかをテストする.
- HFrEFにおける心肺-MSNA反射における異なる単一単位集団の役割を調査する.
主な方法:
- HFrEF患者および対照群における下部体負圧 (LBNP) と正圧 (LBPP) の間における記録されたMSNAおよび中央静脈圧.
- 単一ユニットのMSNA放出を"予期" (古典的なネガティブフィードバック) または"パラドックス" (逆の反応) と分類する.
主要な成果:
- LBPP (増加した充填圧) は,対照群と比較して,HFrEF単一の単位のより大きな割合でパラドックスな反射刺激を誘発した (7:18 vs 24:6,P=0.0001).
- LBPPは,HFrEFにおける単一ユニットの平均発射頻度を増加させ,複数のユニットのMSNAを抑制しませんでした.
- HFrEF単体ユニット (12/18) の有意な割合は,増加した圧力と減少した圧力の両方で発火を増加させた.
結論:
- HFrEFにおける前負荷の増加による増幅された興奮性心肺-MSNA反射のヒトでの最初の証拠を提供します.
- HFrEFにおけるこの反射に対する2つの単一ユニット集団の異なる貢献を強調しています.
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