異常なノレピネフリンクリアランスとアドレネルゲン受容体の感受性は,イディオパシー・オーソスタティック不耐性において
G Jacob1, J R Shannon, F Costa
1Nathan Blaser Shy-Drager Research Program, Autonomic Dysfunction Center, Departments of Medicine, Pharmacology, and Neurology, Vanderbilt University Medical Center, Nashville, TN, USA.
Circulation
|April 6, 1999
まとめ
慢性矯正性不耐症 (OI) の患者は,交感神経系の機能障害を示します. 彼らの体はノレピネフリン (NE) を調節し得ず,刺激に対して異常な反応をしており,これは心血管制御の障害を示している.
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
- 神経科学は神経科学である.
背景:
- 慢性矯正不耐症 (OI) は,立ち上がった時に脳への血流が不十分な症状を伴う.
- 典型的なOIは,血圧の大幅な低下なしに心拍数 (>30bpm) の有意な上昇によって特徴付けられます.
- 潜在的な原因には,低血量,部分的自律機能不全,またはハイパーアドレナジック状態が含まれます.
研究 の 目的:
- OI患者の心血管反応を制御する自律神経細胞の機能異常を調査する.
- 慢性OIにおける交感性心血管調節障害の仮説を検証する.
主な方法:
- 13人のOI患者と10人の対照群を,自律機能テストを用いて比較した.
- 測られた全身性ノレピネフリン (NE) 運動量 (溢出,クリアランス) 仰向けと立った状態.
- ティラミン,アドレネルゲンアゴニスト (イソプロテレノール,フェニルエフリン),バロレフレクスの感受性,内在心拍数に対する評価反応.
主要な成果:
- OIの患者は,対照群と比較して,立った時にNEのクリアランスが低下した.
- チラミン投与は,対照群とは異なり,OI患者におけるNEの転移を有意に増加させなかった.
- OI患者には,イソプロテレノールとフェニルエフリンに対する感受性が高まり,バロレフレクスの感受性が低下しました.
結論:
- 慢性的なOIの患者は,同情性心血管調節の有意な障害を示しています.
- 重要な発見には,NEクリアランスの低下,ティラミンに対する鈍感な反応,およびアドレネルゲンアゴニストに対する過敏性の上昇が含まれています.
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