储存器调节突触修饰的极性和输入特异性
M Nishiyama1, K Hong, K Mikoshiba
1Department of Biology, University of California at San Diego, La Jolla 92093-0357, USA.
Nature
|December 16, 2000
概括
活动诱导的突触可塑性,如长期强化 (LTP) 或抑郁 (LTD),取决于后突触. 的流入和从内部储存中释放调节突触修饰的极性和特异性.
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:
- 突触修饰,包括长期强化 (LTP) 和长期抑郁 (LTD),对于神经系统的发育和可塑性至关重要.
- 突触功效的活动依赖性变化对学习和记忆至关重要.
- 一个关键的问题是,这些修改是否仅限于激活的突触.
研究的目的:
- 研究 postsynaptic流入和内部储存在调节突触可塑性的作用.
- 为了确定长期强化 (LTP) 和长期抑郁 (LTD) 诱导的输入特异性.
- 阐明活动诱导的突触修饰的极性和特异性背后的机制.
主要方法:
- 在海马的CA1区域的电生理学记录.
- 药理学阻断NMDA (N-甲基-D-酸盐) 受体以调节后突触流入.
- 抑制瑞诺丁受体和伊诺西三酸盐 (InsP3) 受体以研究细胞内释放.
- 1型InsP3受体的遗传删除.
主要成果:
- 部分阻断NMDA受体将LTP转换为LTD,并在异质突触输入处诱导LTD.
- 诱导同性突触的LTD需要功能性氨酸受体,而异位突触的LTD需要InsP3受体.
- 阻断氨酸受体消除了同类突触的LTD,但并没有消除异质突触的LTD.
- 1型InsP3受体的遗传删除将LTD转换为LTP,并消除了异质突触LTD.
结论:
- 后突触受和InsP3受体的流入和释放的影响,决定了突触修饰的方向 (LTP/LTD) 和特异性.
- 细胞内储量的差异激活在确定同性突触与异质突触可塑性方面发挥着至关重要的作用.
- 这些发现揭示了一个复杂的机制,控制基于动态的突触可塑性.
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