ノルエピネフリントランスポーター欠乏症のマウスは,過度の心拍動脈と高血圧を示し,覚醒と活動に伴います
Nancy R Keller1, André Diedrich, Martin Appalsamy
1Autonomic Dysfunction Center, Department of Medicine, Nashville, TN 37232-2195, USA.
Circulation
|September 1, 2004
まとめ
ネズミのノルエピネフリントランスポーター (NET) 欠乏症は,特に活動中に,高血圧と心拍数につながる. 中央の交感抑制は正常な休息状態を維持するのに役立ちますが,交感活性化は周辺の信号伝達を増幅します.
科学分野:
- 心血管の生理学 心血管の生理学
- 神経伝達物質の輸送は神経伝達物質によるものです.
- 自律神経系の調節 自動神経系の調節
背景:
- ノルエピネフリン (NE) は,自律的調節と交感神経機能のための重要な神経伝達物質です.
- ノルエピネフリントランスポーター (NET) は,NEシグナル伝達を調節し,様々な薬剤によって標的にされます.
- NET機能不全は,矯正不耐性などの心血管疾患に関連しています.
研究 の 目的:
- ノルエピネフリン再吸収の障害による心臓血管疾患の影響を調査するために.
- 心血管ホメオスタシスの維持におけるノレピネフリントランスポーター (NET) の役割を評価する.
- NET欠陥が体内の自律的調節に与える影響を検証する.
主な方法:
- NET欠乏性 (NET(-/-)) と野生型 (NET(+/+)) のマウスのテレメトリックモニタリング.
- 平均動脈圧と心拍数を含む心血管のパラメータの測定.
- 血カテキオラミン (NE,エピネフリン,ドーパミン) および他のカテキオール濃度の分析.
主要な成果:
- NET ((-/-) マウスは,対照群と比較して,平均動脈圧と心拍数が上昇した.
- 活動中のNET(-/-) マウスでは,心血管のパラメータが有意に増加した.
- プラズマNE濃度は高かったが,二酸化水素フェニルグリコール濃度はNETのマウスで低かったので,NEの再吸収が減少したことを示した.
結論:
- NET欠乏症は,心臓血管機能の変化,特に交感性活性化中に,高血圧と高心拍を伴う.
- 中枢交感抑制は,静止状態のNET欠陥を補うことができるが,この調節は活動中に克服される.
- この発見は,NETが,外周カテコアミナージックシグナル伝達と心血管の安定を調節する上で果たす重要な役割を強調しています.
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