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A Low Cost Setup for Behavioral Audiometry in Rodents
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人間における非常に低周波のRR区間振動の基礎となるメカニズム
J A Taylor1, D L Carr, C W Myers
1Department of Internal Medicine, Hunter Holmes McGuire Department of Veterans Affairs Medical Center, and Medical College of Virginia, Virginia Commonwealth University, Richmond, USA. ataylor@mail.hrca.harvard.edu
Circulation
|August 26, 1998
まとめ
心臓発作後の生存に不可欠な非常に低周波の心拍数変動は,主にパラシンパティック神経系によって引き起こされます. レニン・アニオテンシン・アルドステロン系も重要な役割を果たしますが,静脈管の調子は心臓血管の健康にとって重要です.
科学分野:
- 心血管生理学 心血管の生理学
- 自律神経系の規制について
- 心拍数変数分析 心拍数変数分析
背景:
- 非常に低頻度 (VLF) のRR区間の変動性の低下は,心筋梗塞後の患者の生存率の低下と関連しています.
- VLFの振動の生理学的基礎は,まだ完全に理解されていません.
- この研究では,VLFの変動性における共感性,ヴァガル,およびレニン-アニオテンシン-アルドステロンシステムの役割を調査しています.
研究 の 目的:
- VLF RR間隔の変動に対する自律的およびホルモンによる貢献を明らかにする.
- VLFの振動に対するβ-アドレナergic,parasympathetic,およびACE阻害の影響を区分する.
- 健康な若い被験者におけるVLFの変動の生理学的根拠を理解する.
主な方法:
- RR間隔と動脈圧は,10人の健康な被験者に,仰向けと傾斜の姿勢で記録されました.
- 薬理学的封鎖には,塩水 (コントロール),アテノロール (ベータ封鎖),アトロピン (パラシンパティック封鎖),複合封鎖,エナラプリラット (ACE封鎖) が含まれていた.
- 急速なフーリエ変換解析により,非常に低い,低い,および呼吸器周波数帯のスペクトル電力を定量化しました.
主要な成果:
- アトロピンによるパラシンパシー阻害は,VLF帯における全体的なRR区間の変動性を92%大幅に減少させた.
- ベータ・アドレナージック・ブロックは,VLFや低周波電力に有意な影響を及ぼさなかったが,呼吸器周波数電力が増加した.
- ACE阻害は,仰向け状態でのVLF電力をわずかに増加させた (~21%),傾斜状態では増加しなかった.
結論:
- VLFのRR-インターバルのリズムは,主にパラシンパティック神経系の活動に依存しています.
- レニン-アニオテンシン-アルドステロン系は,VLFの変動性に二次的な影響を及ぼします.
- VLFの振動の予後的意義は,パラシンパシー機能と心血管の健康との強い関連から生じる可能性が高い.
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