快速的神经递质释放由Ca流入通过AMPA类型的谷氨酸受体触发
Andrés E Chávez1, Joshua H Singer, Jeffrey S Diamond
1Synaptic Physiology Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892-3701, USA.
Nature
|October 13, 2006
概括
视网膜中的反抑制依赖于一种新的机制. 从A17亚马克林细胞释放的GABA是由透的AMPA受体触发的,而不是电压关闭的通道,揭示了一个新的神经电路路径.
科学领域:
- 神经科学是一个神经科学.
- 视网膜生理学视网膜生理学
- 突触传输是突触传输的过程.
背景情况:
- 在A17亚马克林细胞和棒双极细胞 (RBCs) 之间的相互突触对于视网膜光引起的反应至关重要.
- 由GABA (氨酸) 介导的反抑制从A17细胞到红细胞形成视觉处理.
- 从A17细胞树突中释放GABA的确切机制仍未确定.
研究的目的:
- 阐明控制GABA从A17亚马克林细胞释放的分子机制.
- 调查电压通道 (VGCCs) 是否在这些突触中调解GABA释放.
- 为了确定参与反抑制的源和信号通路.
主要方法:
- 在老鼠视网膜切片中的电生理学记录.
- 对受体和离子通道的药理学操纵.
- 成像技术用于监测细胞内动态.
主要成果:
- 从A17细胞释放的GABA独立于VGCC和膜脱极化.
- 通过透AMPA受体 (AMPARs) 流入会触发GABA的释放.
- 由AMPAR介导的信号由内部储存中的诱导的释放 (CICR) 放大.
结论:
- 一种新的快速突触传播形式,独立于VGCCs,在视网膜中运行.
- 透性AMPAR和CICR对于A17亚马克林和红细胞电路中的反抑制至关重要.
- 这一发现揭示了以前未知的调节视网膜中神经电路活动的机制.
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