在视网膜中发展非对称抑制的基础方向选择性
Wei Wei1, Aaron M Hamby, Kaili Zhou
1Department of Molecular & Cell Biology, University of California, Berkeley, California 94720-3200, USA.
Nature
|December 7, 2010
概括
神经回路发展出不对称的突触强度. 星爆亚马克林细胞 (SACs) 在它们的零侧加强了方向选择性质细胞 (DSGCs) 的抑制输入,独立于神经活动.
科学领域:
- 神经科学是一个神经科学.
- 发展生物学 发展生物学
- 突触性可塑性 突触性可塑性
背景情况:
- 精确的突触连接对于功能神经回路至关重要.
- 视网膜的方向选择性取决于从星爆亚马克林细胞 (SAC) 到ON-OFF方向选择性质细胞 (DSGC) 的抑制输入.
- 以前的研究表明,子中的SAC和DSGC之间存在不对称的GABAergic突触,但发育机制仍然未知.
研究的目的:
- 研究SACs和DSGCs之间建立不对称的突触连接的基础的发展过程.
- 确定神经活动是否影响方向选择性的发展.
主要方法:
- 利用具有细胞类型特定标记的转基因小鼠进行详细的突触分析.
- 在不同发育阶段 (产后第一周和第二周) 从SAC到DSGC的突触强度进行比较.
- 使用肌肉醇和 gabazine 阻止视网膜活动,以评估其在突触发育中的作用.
主要成果:
- 最初,SAC-DSGC突触连接在第一个产后周期间,在偏好和零两侧都表现出相同的强度.
- 到第二个产后周,来自零侧SAC的突触显著加强,而优先侧突触保持不变.
- 阻断视网膜活动没有影响不对称抑制或方向选择性的发展.
结论:
- 在方向选择性视网膜电路中的不对称抑制是通过一个发育程序建立的.
- 这个程序特别加强了从零侧SACs的GABA介导输入.
- 这些突触的加强独立于神经活动发生.
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