Ryan L J, Clark K B
Department of Psychology, Oregon State University, Corvallis 97331-5303.
Brain Res Bull. 1992 Sep-Oct;29(3-4):319-27. doi: 10.1016/0361-9230(92)90063-4.
Kainic acid (2-4 days) or ibotenic acid (7-9 days) lesions of the globus pallidus or neostriatum altered the responsiveness of subthalamic nucleus neurons to electrical stimulation of the agranular frontal cortex. Three changes in responsiveness were seen following pallidal lesion: a) An increase in the proportion of responding cells as compared to controls (approximately 90% vs. 60%); b) an increase in the total duration of the evoked response (62.5 ms vs. 28.6 ms); 3) an increase in magnitude of response (9.76 spikes per stimulus vs. 3.24). Both an increase in firing rate (17.94 spikes/s vs. 8.23) and a change to a bursty spontaneous firing pattern were seen. Lesion of the neostriatum had fewer but opposite effects including decreased firing rate (7.21 spikes/s) and decreased total response duration (18.9 ms). These results suggest that the normal tonic inhibition of the subthalamic nucleus by the globus pallidus may play an important role in controlling subthalamic neuronal spontaneous activity and responsiveness. The neostriatum may influence the subthalamic nucleus via the globus pallidus. Globus pallidus lesions may have important consequences on the specificity of cortical control of the subthalamic nucleus and may alter subthalamic influence on basal ganglia output.
苍白球或新纹状体的 kainic 酸（2 - 4 天）或鹅膏蕈氨酸（7 - 9 天）损伤改变了丘脑底核神经元对颗粒前皮质电刺激的反应性。苍白球损伤后可见反应性的三种变化：a）与对照组相比，反应细胞比例增加（约 90% 对 60%）；b）诱发反应的总持续时间增加（62.5 毫秒对 28.6 毫秒）；3）反应幅度增加（每次刺激 9.76 个峰电位对 3.24）。同时观察到放电率增加（17.94 个峰电位/秒对 8.23）以及自发放电模式转变为爆发性模式。新纹状体损伤的影响较少但相反，包括放电率降低（7.21 个峰电位/秒）和总反应持续时间缩短（18.9 毫秒）。这些结果表明，苍白球对丘脑底核的正常紧张性抑制可能在控制丘脑底核神经元的自发活动和反应性中起重要作用。新纹状体可能通过苍白球影响丘脑底核。苍白球损伤可能对丘脑底核的皮质控制特异性产生重要影响，并可能改变丘脑底核对基底神经节输出的影响。
