ヒトシノアトリアルノードへのパラシンパティック神経繊維の選択的刺激
1Department of Pathology, University Hospitals of Cleveland/Case Western Reserve University, Ohio 44106.
Circulation
|April 1, 1992
まとめ
人間の表心脂肪パッドのパラシンパティック神経繊維は,心房循環の長さを増加させるために刺激することができます. シノアトリアルノード神経のこの選択的刺激は,心房脈伝導に影響を及ぼさなかった.
科学分野:
- 心臓病学 心臓病学
- 神経科学は神経科学である.
- 自律神経系とは,自律神経系である.
背景:
- 動物のシナトリアノードを神経化するパラシンパティック神経繊維は,心房循環の長さを増加させることができます.
- これらの神経は,シノアトリアル節の近くにある表心脂肪パッドに位置しています.
- 人間にも同様の神経が存在し,刺激される可能性があるという仮説を立てた.
研究 の 目的:
- ヒトの表心臓の脂肪パッドにパラシンパティック神経の存在を調査するために.
- これらの神経を選択的に刺激して心拍数に影響を与えるかどうかを判断する.
- 刺激が心房循環の長さや心房回路伝導に与える影響を評価する.
主な方法:
- 人間の解剖で得られた心臓の脂肪パッドの顕微鏡検査.
- 16人の心臓外科手術患者の上心筋脂肪パッドの電気刺激.
- 刺激周波数 (6.6~30 Hz) を変化させ,心房循環の長さとPR間隔を測定する.
主要な成果:
- 神経繊維とギャングリアは,ヒトの心臓の脂肪パッドで特定されました.
- 電気刺激は,周波数に依存した方法で心房のサイクル長さを大幅に増加させた.
- 鼓動中の心房伝導時間とPR間隔は変化しませんでした.
結論:
- 人間の表心脂肪パッドのパラシンパティック神経繊維は,選択的に刺激することができます.
- この刺激により,心房回路の長さは,心房節伝導に影響を与えることなく効果的に増加します.
- この研究は,ヒトにおけるシナトリアノード-神経神経化神経の最初の選択的刺激を表しています.
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