对增加的阴道活动心房节点反应的形态学和电生理学相关性
S Imaizumi1, T Mazgalev, L S Dreifus
1Department of Medicine, Lankenau Hospital, Philadelphia, PA 19151.
Circulation
|September 1, 1990
概括
阴道刺激通过作用于心 (AV) 节点中的特定细胞来减缓心律. 这种效应集中在中节点区域,影响心脏导电.
科学领域:
- 心血管生理学心血管生理学
- 自主神经系统功能 自主神经系统功能
- 心脏电生理学 心脏电生理学
背景情况:
- 通过心房脉 (AV) 节点减缓心脏脉冲传导的机制是复杂的,涉及解剖学因素,多样化的细胞电生理学和自主神经系统调制.
- 了解神经对AV结节导通的影响的精确位置和细胞点对于理解心律调节至关重要.
研究的目的:
- 为了确定AV节点内心脉冲传导的阴道诱导减速的特定位置.
- 为了将静脉刺激的电生理反应与不同AV节点区域的形态和体化学发现相关联.
主要方法:
- 在静脉动脉节的不同区域进行了 Postganglionic Vagal 刺激.
- 记录了AV结节细胞的电生理反应.
- 在结节组织中检查了形态分析和乙胆化酶 (AChE) 染色模式.
主要成果:
- 阴道刺激导致N区域细胞的局部超极化,与中央AV节点的强烈ACHE染色相关.
- AChE染色密度向AN和His捆区域下降,其中阴道刺激的影响最小.
- 乙胆释放及其抑郁作用集中在中结节N细胞上.
结论:
- 静脉节导通的阴道减缓主要由中枢区域的乙胆释放介导.
- 中结节区域的N细胞是阴道效应的主要目标,导致过极化和压抑的作用潜力.
- 在中结节区域的神经元件和N细胞之间的密切接近促进了心脏导电的聚焦神经调节.
相关概念视频
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