相关实验视频
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Programmed Electrical Stimulation in Mice
Published on: May 26, 2010
在心房和心室回声期间,狗心室节点中的回流回路:电生理学和组织学相关性
Peter Loh1, Siew Yen Ho, Tokuhiro Kawara
1Experimental and Molecular Cardiology Group, Academic Medical Center, Amsterdam, The Netherlands. p.loh@hli.azu.nl
Circulation
|July 2, 2003
概括
这项研究揭示了狗的独特的AV节点区域能够实现双重生理和再进入. 导电阻塞和缓慢导电发生在组织结点,促进心房和心室回声.
科学领域:
- 心血管电生理学 心血管电生理学
- 心脏解剖学 心脏解剖学
- 节律失常的发生 (arrhythmogenesis).
背景情况:
- 对心房 (AV) 节点重新进入的精确解剖基础仍然不完全理解.
- 定位回流回路和识别缓慢导电和阻塞的位置对于理解AV节点功能至关重要.
研究的目的:
- 为了将AV节点组织学与隔离的狗心中的电生理学发现相关联.
- 为了定位负责心房和心室回声的回流回路.
- 在AV节点内对缓慢导电和导电阻塞的部位进行表征.
主要方法:
- 细胞外电活动在高分辨率 (0.3-0.5毫米间电极距离) 记录在Koch的三角形10个隔离狗心脏在心房组织去除后.
- 五颗心脏经历了组织学检查,以将电气记录与组织架构相关联.
- 引发了心房和心室回声来研究重新进入的现象.
主要成果:
- 在心房回声期间,单向导电阻发生在心房过渡细胞结处,在上方心房节点.
- 缓慢导电区被确定在心房-过渡或过渡-紧节点交叉点在较低的AV节点.
- 在心室回声时,传导阻塞发生在顶部AV节点的紧节点 - 过渡细胞结点上,在下部区域有缓慢的传导区域.
结论:
- 组织架构和功能解离在狗中AV节点的上部和下部区域之间的功能解离促进双重生理和重新进入.
- 缓慢导电和功能导电阻主要发生在AV节点区域内不同组织类型之间的结点上.
- 在心房过渡和紧节点过渡细胞结处的特定导电阻塞位解释了心房和心室回声的机制.
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