Nigral Inhibition of GABAergic Neurons in Mouse Superior Colliculus
Nigral Inhibition of GABAergic Neurons in Mouse Superior Colliculus
复制标题
DOI：
10.1523/jneurosci.3263-08.2008
复制
发表时间：
2008-10-22
影响因子：
5.3
通讯作者：
Isa, Tadashi
中科院分区：
文献类型：
--
作者：
Kaneda, Katsuyuki;Isa, Kaoru;Isa, Tadashi
目前关于基底神经节控制跳跃性眼球运动的主流概念是，黑质网状部（SNr）从强直性gaba能抑制中释放出来，触发上丘（SC）中中间灰层（SGI）神经元的爆发，使跳跃性开始。这一假设是基于SNr细胞抑制SGI中的兴奋性投射神经元的假设。在这里，我们发现黑质护壁纤维以与非gaba能神经元相似的频率连接到SGI中的局部gaba能神经元。这是通过对gad67 -绿色荧光蛋白（GFP）敲入小鼠进行神经解剖示踪和切片电生理实验来实现的，gaba能神经元特异性表达GFP。我们还发现，GABA(A)受体，而不是GABA(B)受体，支持黑质脑屏障传递。本研究结果揭示了基底神经节在控制扫视中的作用的一个新方面，即信噪比不仅调节突发启动，还通过与SC中局部gaba能神经元的连接调节前运动神经元的时空特性。
The current dominant concept for the control of saccadic eye movements by the basal ganglia is that release from tonic GABAergic inhibition by the substantia nigra pars reticulata (SNr) triggers burst firings of intermediate gray layer (SGI) neurons in the superior colliculus (SC) to allow saccade initiation. This hypothesis is based on the assumption that SNr cells inhibit excitatory projection neurons in the SGI. Here we show that nigrotectal fibers are connected to local GABAergic neurons in the SGI with a similar frequency to non-GABAergic neurons. This was accomplished by applying neuroanatomical tracing and slice electrophysiological experiments in GAD67-green fluorescent protein (GFP) knock-in mice, in which GABAergic neurons specifically express GFP. We also found that GABA(A), but not GABA(B), receptors subserve nigrotectal transmission. The present results revealed a novel aspect on the role of the basal ganglia in the control of saccades, e. g., the SNr not only regulates burst initiation but also modulates the spatiotemporal properties of premotor neurons via connections to local GABAergic neurons in the SC.