In vivo induction of striatal long-term potentiation by low-frequency stimulation of the cerebral cortex
In vivo induction of striatal long-term potentiation by low-frequency stimulation of the cerebral cortex
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DOI：
10.1016/s0306-4522(98)00719-2
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发表时间：
1999-01-01
期刊：
影响因子：
3.3
通讯作者：
Deniau, JM
中科院分区：
文献类型：
--
作者：
Charpier, S;Mahon, S;Deniau, JM
长时程抑制和长时程增强在皮质纹状体突触中都有描述。这些突触强度的长期变化通常是由皮层传入神经的高频（100 Hz）电刺激引起的。本研究的目的是测试皮质纹状体连接表达使用依赖性修饰的能力，皮质刺激后，在我们的体内制备中观察到的皮质纹状体输入的同步频率，即巴比妥酸盐麻醉大鼠。在这项研究中，我们使用了一个确定的单突触皮质纹状体通路，口面运动皮质和其目标区域之间的纹状体。纹状体输出神经元的细胞内记录显示自发的大幅度振荡样去极化表现出较强的周期性与窄频带在5 Hz。利用投射到记录细胞的皮层区域的局灶性脑电图，我们发现纹状体神经元的膜电位振荡与自发皮层纺锤波的发作是同相的。为了直接确定皮质纹状体神经元的活动模式，我们进行了细胞内记录的电生理鉴定皮质纹状体神经元同时与相应的表面脑电图。我们发现，皮质纹状体细胞（n = 7）表现出自发的5-Hz放电的阶段与皮质纺锤波。因此，我们已经测试了在这种低频率（5 Hz，500-1000脉冲）下重复皮层刺激对皮质纹状体突触功效的影响。在62%的情况下（13个神经元中的8个测试），这种条件能够产生长时程增强的皮质纹状体突触的功效。兴奋性突触后电位振幅平均增加13.3%~ 172%（平均67.3%，n = 8），这些结果为皮质纹状体连接的生理性长时程增强提供了额外的支持。此外，本研究表明，皮质纹状体长时程增强可以诱导同步在低频率的皮层传入。我们的数据支持的概念，纹状体输出神经元可能作为一个重合探测器的会聚皮层信息。(C)1999年IBRO。出版社：Elsevier Science Ltd
Both long-term depression and long-term potentiation have been described at corticostriatal synapses. These long-lasting changes in synaptic strength were classically induced by high-frequency (100 Hz) electrical stimulations of cortical afferents. The purpose of the present study was to test the ability of corticostriatal connections to express use-dependent modifications after cortical stimulation applied at the frequency of synchronization of corticostriatal inputs observed in our in vivo preparation, i.e. the barbiturate-anesthetized rat. For this study we used an identified monosynaptic corticostriatal pathway, between the orofacial motor cortex and its target region in the striatum. Intracellular recording of striatal output neurons showed spontaneous large-amplitude oscillation-like depolarizations exhibiting a strong periodicity with a narrow frequency band at 5 Hz. Using the focal electroencephalogram of the cortical region projecting to the recorded cells, we found that membrane potential oscillations in striatal neurons were in phase with episodes of spontaneous cortical spindle waves. To determine directly the pattern of activity of corticostriatal neurons, we performed intracellular recordings of electrophysiologically identified corticostriatal neurons simultaneously with the corresponding surface electroencephalogram. We found that corticostriatal cells (n = 7) exhibited periods of spontaneous 5-Hz discharges in phase with the cortical spindle waves. Therefore, we have tested the effect of repetitive cortical stimulations at this low frequency (5 Hz, 500-1000 pulses) on the corticostriatal synaptic efficacy. In 62% of cases (eight of 13 neurons tested), this conditioning was able to produce long-term potentiation in the corticostriatal synaptic efficacy. The mean increase of excitatory postsynaptic potential amplitude ranged from 13.3% to 172% (mean = 67.3%, n = 8).These results provide additional support for physiological long-term potentiation at corticostriatal connections. Furthermore, this study demonstrates that corticostriatal long-term potentiation can be induced by synchronization at low frequency of cortical afferents. Our data support the concept that the striatal output neuron may operate as a coincidence detector of converging cortical information. (C) 1999 IBRO. Published by Elsevier Science Ltd.