透AMPA受体的突触活性诱导受体亚型中的切换
1Department of Pharmacology, University College London, UK.
Nature
|June 6, 2000
概括
突触活动迅速改变大脑星状细胞中的α-amino-3-hydroxy-5-methyl-4-isoxazole酸受体 (AMPAR) 组成. 这种变化通过结合含有GluR2的AMPARs来改变突触传输,调节的透性.
科学领域:
- 神经科学是一个神经科学.
- 突触性可塑性 突触性可塑性
- 分子生物学分子生物学
背景情况:
- 活动依赖的突触可塑性对中枢神经系统的功能至关重要.
- 后突触修饰通常涉及α-amino-3-hydroxy-5-methyl-4-isoxazole酸受体 (AMPAR) 响应性的变化.
- 现有的模型表明AMPAR数和酸化状态的变化驱动了这些变化.
研究的目的:
- 研究一种新型的突触可塑性,涉及AMPAR亚单元组成和Ca2+透性.
- 阐明GluR2亚单元在小脑星状细胞突触中的活动依赖性突触修饰中的作用.
主要方法:
- 利用电生理学技术来监测突触电流.
- 研究了AMPARs的Ca2+透性和聚胺阻断.
- 在突触刺激后跟踪了含有GluR2的AMPARs的结合.
主要成果:
- 确定了AMPAR亚单元组成和大脑星状细胞突触中的Ca2+透性的快速,持久的变化.
- 证明了Ca2+透性AMPARs的重复突触激活导致Ca2+透性降低.
- 表明通过缺乏GluR2的AMPARs产生的活性诱导的Ca2+流入调节了含有GluR2的AMPARs的向.
结论:
- 通过缺乏GluR2的AMPARs,依赖活动的Ca2+流入控制了含有GluR2的AMPARs的结合.
- 这一过程代表了突触传输效率的自我调节机制.
- 突出了一种新型的突触可塑性,这种可塑性是由AMPAR亚单元组成的变化介导的.
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