動脈活動の増加に対する心房動脈結節応答の形態学的および電気生理学的相関値
S Imaizumi1, T Mazgalev, L S Dreifus
1Department of Medicine, Lankenau Hospital, Philadelphia, PA 19151.
Circulation
|September 1, 1990
まとめ
ヴァガル刺激は,心房 (AV) 節の特定の細胞に作用することで,心拍を遅らせます. この効果はミドノダル領域に集中し,心臓伝導に影響を与えます.
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
- 心臓電気生理学 心臓電気生理学
背景:
- 心房中枢 (AV) ノードを通る心臓のインパルス伝導を遅らせるメカニズムは,解剖学的要因,多様な細胞電気生理学,および自律神経系調節を含む複雑です.
- AV結節伝導に対する神経の影響の正確な位置と細胞標的を理解することは,心拍の調節を理解するために不可欠です.
研究 の 目的:
- AVノード内の心臓のインパルス伝導の Vagally Induced 減速の特定の場所を特定するために.
- ヴァガル刺激に対する電気生理学的反応と,異なるAV節節領域における形態学的および組織化学的発見を相関させる.
主な方法:
- 静脈関節の特定の部位にポストガンリオン静脈 stimulation を施した.
- AV結節細胞の電気生理学的反応が記録されました.
- 形態学的分析とアセチルコリネステラゼ (AChE) 染色パターンが,結節組織で調べられました.
主要な成果:
- ヴァガル刺激は,N領域の細胞の局所的ハイパーポラライゼーションを引き起こし,中央AVノードにおける激しいACHE染色と相関する.
- AChEの染色密度はANとHisバンドル領域に向かって減少し,そこでは静脈刺激が最小限の効果を持っていた.
- アセチルコリンの放出とその抑うつ作用は,中節N細胞に集中していました.
結論:
- AV結節伝導の Vagus 減速は,主に midnodal 領域でのアセチルコリン放出によって媒介されます.
- 中枢結節領域のN細胞は,気管効果の主要な標的であり,超極化と抑えたアクションポテンシャルにつながります.
- ミドノダル領域の神経要素とN細胞の密接な接近は,心臓伝導の集中神経調節を促進します.
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