Excitatory cortical inputs to pallidal neurons via the subthalamic nucleus in the monkey
Excitatory cortical inputs to pallidal neurons via the subthalamic nucleus in the monkey
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DOI：
10.1152/jn.2000.84.1.289
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发表时间：
2000-07-01
影响因子：
2.5
通讯作者：
Hasegawa, N
中科院分区：
文献类型：
--
作者：
Nambu, A;Tokuno, H;Hasegawa, N
运动相关皮质区如何调节基底节输出核团的活动是理解基底节运动控制机制的重要问题。在本研究中，使用清醒的猴子，在前肢区的初级运动和初级躯体感觉皮层的电刺激对苍白球（GP）神经元活动的多突触效应，特别是通过丘脑底核（GNF）介导的，已被表征。皮层刺激诱导的早期，短潜伏期的兴奋，然后抑制和迟兴奋的神经元的外部和内部段的GP。它还引起了早期，短潜伏期兴奋，随后是一个晚兴奋和抑制的神经元。海马神经元的早期兴奋早于GP神经元。蝇蕈醇（GABAA受体激动剂）注射阻断GP神经元的活动，导致皮层刺激引起的GP神经元的早期和晚期兴奋被取消。与此同时，GP神经元的自发放电频率降低，放电峰群间的停顿变得明显，放电模式变得规则。注射（+/-）-3-（2-羧基哌嗪-4-基）丙基-1-膦酸（CPP）[N-甲基-D-天冬氨酸（NMDA）受体拮抗剂]，但不包括1，2，3，4-四氢-6-硝基-2，3-二氧代苯并[ f]喹喔啉-7-磺酰胺二钠[NBQX（非NMDA受体拮抗剂）]，进入海马减弱GP神经元的早期和晚期兴奋，表明皮质-丘脑底传递主要由NMDA受体介导。将荷包牡丹碱（GABAA受体拮抗剂）注入丘脑底核，干扰苍白球-丘脑底核传递，使抑制明显，但不影响早期兴奋。目前的研究结果表明，皮质-丘脑底核-苍白球通路传达强大的兴奋性的影响，从运动相关的皮质区的GP与较短的传导时间比通过纹状体传达的效果。
How the motor-related cortical areas modulate the activity of the output nuclei of the basal ganglia is an important issue for understanding the mechanisms of motor control by the basal ganglia. In the present study, by using awake monkeys, the polysynaptic effects of electrical stimulation in the forelimb regions of the primary motor and primary somatosensory cortices on the activity of globus pallidus (GP) neurons, especially mediated by the subthalamic nucleus (STN), have been characterized. Cortical stimulation induced an early, short-latency excitation followed by an inhibition and a late excitation in neurons of both the external and internal segments of the GP. It also induced an early, short-latency excitation followed by a late excitation and an inhibition in STN neurons. The early excitation in STN neurons preceded that in GP neurons. Blockade of STN neuronal activity by muscimol (GABAA receptor agonist) injection resulted in abolishment of both the early and late excitations evoked in GP neurons by cortical stimulation. At the same time, the spontaneous discharge rate of GP neurons decreased, pauses between the groups of spikes of GP neurons became prominent, and the firing pattern became regular. Injection of (+/-)-3-(2-carboxypiperazin-4-yl) propyl-1-phosphonic acid (CPP) [N-methyl-D-aspartate (NMDA) receptor antagonist], but not 1,2,3,4-tetrahydro-6-nitro-2,3-dioxobenzo[ f] quinoxaline-7-sulfonamide disodium [NBQX (non-NMDA receptor antagonist)], into the STN attenuated the early and late excitations in GP neurons, suggesting that cortico-subthalamic transmission is mediated mainly by NMDA receptors. Interference with the pallido-subthalamic transmission by bicuculline (GABAA receptor antagonist) injection into the STN made the inhibition distinct without affecting the early excitation. The present results indicate that the cortico-subthalamo-pallidal pathway conveys powerful excitatory effects from the motor-related cortical areas to the GP with shorter conduction time than the effects conveyed through the striatum.