双心室节点输入的选择性功能性质. 在子心脏中节点导电,折射性,总和和速度依赖功能的作用
1Department of Physiology, Faculty of Medicine, University of Montreal, Quebec, Canada.
Circulation
|August 15, 1996
概括
这是心房心室节点.
科学领域:
- 心血管生理学心血管生理学
- 心脏电生理学 心脏电生理学
背景情况:
- 内心心室节点 (AVN) 接收来自下末端和下间隔膜的激活信号.
- 这些输入之间的功能不对称性与节点回入节律有关.
研究的目的:
- 为了研究AVN输入的选择性功能特性.
- 为了确定这些输入在节点传导,折射性,总和和速率依赖功能的作用.
主要方法:
- 隔离的子心脏制剂被用于表征结节性质 (恢复,促进,疲劳).
- 刺激协议的不同输入阶段,节点功能状态和输入参考.
- 多因素ANOVA评估了对导电时间,恢复时间和耐火期的影响.
主要成果:
- 刺激阶段显著影响节点导电时间,但不影响耐火期或恢复时间常数.
- 个别输入显示基于相位,参考和合间隔的可变导电时间.
- 从低或低隔膜进行节奏,产生了类似的导电和耐火值.
- 输入总和并没有提高激活节点的个人输入效率.
- 节点表面记录证实了功能对称性和同等输入效率,其影响局部化到近端节点.
结论:
- 这两个AVN输入具有同等的功能性质.
- 这两种输入都同样有效地激活AVN的取决于速率的部分.
- 输入相互作用会影响周节点激活,但不会影响速度依赖的节点功能.
相关概念视频
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