The origin of the complex spike in cerebellar Purkinje cells.
The origin of the complex spike in cerebellar Purkinje cells.
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DOI：
10.1523/jneurosci.0559-08.2008
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发表时间：
2008-07-23
期刊：
影响因子：
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通讯作者：
Häusser M
中科院分区：
文献类型：
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作者：
Davie JT;Clark BA;Häusser M
攀爬纤维输入的激活通过数百个分布广泛的树突突触强烈地刺激小脑浦肯野细胞，触发树突棘波以及被称为复合棘波的体细胞棘波的特征性高频爆发。为了研究树突棘波与体细胞复合体棘波内小穗之间的关系，并评价树突分布对攀缘纤维突触的重要性，我们对小脑切片浦肯野细胞进行了同时的体细胞和树突膜片钳记录。在索马使用动态钳注射大攀爬纤维样突触电导足以重现复杂的尖峰，独立于树突状尖峰，表明既不需要树突状突触分布，也不需要树突状尖峰。此外，我们还发现，在复合穗中，树突状穗与小穗不直接相连，每个树突状穗仅与0.24 ± 0.09个额外的体细胞小穗相连。相反，我们表明，树突棘调节暂停射击后，复杂的尖峰。最后，使用双重体细胞和轴突记录，我们表明，所有小穗在复杂的穗轴突产生。因此，复杂的尖峰生成相对独立于树突尖峰进行，反映了攀爬纤维输入的双重功能作用：在树突突触处触发可塑性并在轴突中产生独特的输出信号。树突棘波的编码后复杂的尖峰暂停提供了一种新的计算功能的树突棘波，这可能有助于连接这两个角色在小脑深核的靶神经元的水平。
Activation of the climbing fiber input powerfully excites cerebellar Purkinje cells via hundreds of widespread dendritic synapses, triggering dendritic spikes as well as a characteristic high-frequency burst of somatic spikes known as the complex spike. To investigate the relationship between dendritic spikes and the spikelets within the somatic complex spike, and to evaluate the importance of the dendritic distribution of climbing fiber synapses, we made simultaneous somatic and dendritic patch-clamp recordings from Purkinje cells in cerebellar slices. Injection of large climbing fiber-like synaptic conductances at the soma using dynamic clamp was sufficient to reproduce the complex spike, independently of dendritic spikes, indicating that neither a dendritic synaptic distribution nor dendritic spikes are required. Furthermore, we found that dendritic spikes are not directly linked to spikelets in the complex spike, and that each dendritic spike is associated with only 0.24 ± 0.09 extra somatic spikelets. Rather, we demonstrate that dendritic spikes regulate the pause in firing that follows the complex spike. Finally, using dual somatic and axonal recording, we show that all spikelets in the complex spike are axonally generated. Thus, complex spike generation proceeds relatively independently of dendritic spikes, reflecting the dual functional role of climbing fiber input: triggering plasticity at dendritic synapses and generating a distinct output signal in the axon. The encoding of dendritic spiking by the post-complex spike pause provides a novel computational function for dendritic spikes, which could serve to link these two roles at the level of the target neurons in the deep cerebellar nuclei.