Milner K L, Mogenson G J
Department of Physiology, University of Western Ontario, London, Canada.
Brain Res. 1988 Jun 14;452(1-2):273-85. doi: 10.1016/0006-8993(88)90031-5.
The locomotor activity of freely moving rats was increased by electrical stimulation of brainstem sites, including the pedunculopontine nucleus, a major component of the mesencephalic locomotor region (MLR), and sites located in the subthalamic locomotor region (SLR), which is in the area of the zona incerta (ZI) dorsomedial to the subthalamic nucleus. Injections to the MLR of glycine, an inhibitory transmitter of the spinal cord and brainstem, had no effect on locomotion, nor did strychnine sulfate, a glycine antagonist. Unilateral injections of the excitatory amino acid, N-methyl-D-aspartic acid (NMDA), and kainic acid, a glutamate analogue, into the MLR produced an increase in locomotion not seen with glutamate, an excitatory amino acid, into the same area. A still greater response, having a later onset than NMDA but also a longer duration, was produced by administration of picrotoxin and bicuculline methiodide, GABA antagonists, to the MLR. Carbachol injections into the MLR produced two types of responses: either increased or decreased locomotion. Hypermotility resulted from microinjections of glutamate, and picrotoxin and bicuculline, into the ZI. The short latency, short duration response to glutamate resulted in a greater increase in locomotion than with picrotoxin or bicuculline when each was administered into the SLR. These results provide further evidence for the functional role of the MLR and SLR in the initiation of locomotor activity in the intact, freely behaving rat.
对包括脑桥脚核（中脑运动区（MLR）的主要组成部分）以及位于丘脑底运动区（SLR）（在丘脑底核背内侧的未定带（ZI）区域）在内的脑干部位进行电刺激，可增加自由活动大鼠的运动活性。向MLR注射脊髓和脑干的抑制性递质甘氨酸，对运动没有影响，甘氨酸拮抗剂硫酸士的宁也无此作用。向MLR单侧注射兴奋性氨基酸N-甲基-D-天冬氨酸（NMDA）以及谷氨酸类似物 kainic 酸，可使运动增加，而向同一区域注射兴奋性氨基酸谷氨酸则不会出现这种情况。向MLR施用GABA拮抗剂印防己毒素和甲碘化荷包牡丹碱，会产生比NMDA起效更晚但持续时间更长的更大反应。向MLR注射卡巴胆碱会产生两种类型的反应：运动增加或减少。向ZI微量注射谷氨酸、印防己毒素和荷包牡丹碱会导致运动亢进。谷氨酸引起的潜伏期短、持续时间短的反应，比向SLR分别注射印防己毒素或荷包牡丹碱时引起的运动增加幅度更大。这些结果为MLR和SLR在完整的自由活动大鼠运动活性启动中的功能作用提供了进一步的证据。
