Basal ganglia efferents to the brainstem centers controlling postural muscle tone and locomotion: A new concept for understanding motor disorders in basal ganglia dysfunction
Basal ganglia efferents to the brainstem centers controlling postural muscle tone and locomotion: A new concept for understanding motor disorders in basal ganglia dysfunction
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DOI：
10.1016/s0306-4522(03)00095-2
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发表时间：
2003-01-01
期刊：
影响因子：
3.3
通讯作者：
Sakamoto, T
中科院分区：
文献类型：
--
作者：
Takakusaki, K;Habaguchi, T;Sakamoto, T
本研究的目的是阐明如何从黑质网状部（SNr）的基底神经节传入中脑桥脑被盖区的脑干有助于步态控制和肌张力调节。我们使用未麻醉和急性去脑猫（n=27），其中纹状体，丘脑和大脑皮层被删除，但SNr被保留。重复刺激（50 Hz，10-60 μ A，5-20 s）施加到中脑运动区（MLR），这对应于楔状核，和邻近地区，诱发自发运动。另一方面，刺激脚桥被盖核（PPN）的肌张力抑制区抑制姿势肌张力。将谷氨酸能激动剂（N-甲基-D-天冬氨酸和红藻氨酸）或GABA拮抗剂（荷包牡丹碱和印防己毒素）注射到MLR和PPN中也分别诱导运动和肌张力抑制。重复电刺激（50-100 Hz，20-60 μ A，5-20 s）单独传递到SNr没有改变肌肉活动。然而，刺激SNr的外侧部分衰减和阻断PPN诱导的肌张力抑制。此外，较弱的刺激的内侧部分的SNr减少了步周期的数量，扰乱了节奏交替的肢体运动的MLR诱导的运动。随着刺激强度的增加，运动的开始被延迟。在更高的强度SNr刺激取消的运动。注射荷包牡丹碱到PPN或MLR减少了SNr的影响上述noted.These结果表明，运动和姿势肌张力受到调制GABA能黑盖-心理的预测有一个部分的功能地形：一个侧面和内侧SNr，调节姿势肌张力和运动，分别。我们的结论是，基底神经节的疾病可能包括黑被盖（基底神经节脑干）系统的功能障碍，从而导致生产异常肌张力和步态障碍。(C)2003年IBRO。由爱思唯尔科技有限公司出版。保留所有权利。
The present study is designed to elucidate how basal ganglia afferents from the substantia nigra pars reticulata (SNr) to the mesopontine tegmental area of the brainstem contribute to gait control and muscle-tone regulation. We used unanesthetized and acutely decerebrated cats (n=27) in which the striatum, thalamus and cerebral cortex were removed but the SNr was preserved. Repetitive stimulation (50 Hz, 10-60 muA, for 5-20 s) applied to a mesencephalic locomotor region (MLR), which corresponded to the cuneiform nucleus, and adjacent areas, evoked locomotor movements. On the other hand, stimulation of a muscle-tone inhibitory region in the pedunculopontine tegmental nucleus (PPN) suppressed postural muscle tone. An injection of either glutamatergic agonists (N-methyl-D-aspartic acid and kainic acid) or GABA antagonists (bicuculline and picrotoxin) into the MLR and PPN also induced locomotion and muscle-tone suppression, respectively. Repetitive electrical stimuli (50-100 Hz, 20-60 muA for 5-20 s) delivered to the SNr alone did not alter muscular activity. However stimulating the lateral part of the SNr attenuated and blocked PPN-induced muscle-tone suppression. Moreover, weaker stimulation of the medial part of the SNr reduced the number of step cycles and disturbed the rhythmic alternation of limb movements of MLR-induced locomotion. The onset of locomotion was delayed as the stimulus intensity was increased. At a higher strength SNr stimulation abolished the locomotion. An injection of bicuculline into either the PPN or the MLR diminished the SNr effects noted above.These results suggest that locomotion and postural muscle tone are subject to modulation by GABAergic nigroteg-mental projections which have a partial functional topography: a lateral and medial SNr, for regulation of postural muscle tone and locomotion, respectively. We conclude that disorders of the basal ganglia may include dysfunction of the nigrotegmental (basal ganglia-brainstem) systems, which consequently leads to the production of abnormal muscle tone and gait disturbance. (C) 2003 IBRO. Published by Elsevier Science Ltd. All rights reserved.