Wilson C J
Brain Res. 1986 Mar 5;367(1-2):201-13. doi: 10.1016/0006-8993(86)91593-3.
Postsynaptic potentials were evoked in neostriatal neurons by stimulation of the ipsilateral and contralateral medial agranular frontal cortical field (AGm) in the rat. This cortical region is known to project bilaterally to the dorsal lateral head of the caudate-putamen of rats. Ipsilateral stimulation of AGm should excite all types of corticostriatal neurons projecting to neostriatal neurons in the corresponding area in neostriatum, while stimulation of the same cortical area on the side contralateral to the recording should evoke synaptic potentials from a more restricted subpopulation of crossed corticostriatal neurons. Neostriatal neuronal responses were recorded intracellularly and spiny projection neurons identified by intracellular staining with horseradish peroxidase. The initial EPSP response to contralateral stimulation was similar to that evoked from the ipsilateral side, except for the absence of a relatively small short latency component responsible for the earliest part of the response to ipsilateral cortical stimulation. Comparison with previous findings indicated that this earliest EPSP component was due to activation of fast-conducting descending cortical efferents with collateral projections exclusively to the ipsilateral neostriatum. Stimulation of contralateral neostriatum evoked responses identical to those obtained using stimulation of contralateral neocortex. Analyses of these responses indicated that both EPSPs arise from activation of the same population of fibers. Stimulation of the contralateral internal capsule just caudal to neostriatum was not effective in evoking the EPSP. Chronic hemidecortication did not change the shape of the EPSP evoked from the intact contralateral side, but reduced its amplitude by approximately one half. These observations indicate that contralaterally projecting corticostriatal neurons in the rat project bilaterally in neostriatum, have axonal branches to the contralateral cerebral cortex as well as neostriatum, and converge onto neostriatal neurons that also receive input from the corresponding cortical region on the ipsilateral side.
通过刺激大鼠同侧和对侧内侧无颗粒额叶皮质区（AGm），在新纹状体神经元中诱发突触后电位。已知该皮质区域双向投射至大鼠尾状核-壳核背外侧头部。同侧刺激AGm应能兴奋投射至新纹状体相应区域新纹状体神经元的所有类型皮质纹状体神经元，而在记录对侧刺激同一皮质区域应能从交叉皮质纹状体神经元的一个更受限亚群诱发突触电位。细胞内记录新纹状体神经元反应，并用辣根过氧化物酶细胞内染色鉴定棘状投射神经元。对侧刺激引发的初始兴奋性突触后电位（EPSP）反应与同侧引发的相似，只是缺少一个相对较小的短潜伏期成分，该成分负责同侧皮质刺激反应的最早部分。与先前研究结果比较表明，这个最早的EPSP成分是由于快速传导的下行皮质传出纤维激活所致，这些纤维具有仅投射至同侧新纹状体的侧支。刺激对侧新纹状体引发的反应与使用对侧新皮质刺激获得的反应相同。对这些反应的分析表明，两种EPSP均源于同一群纤维的激活。在新纹状体尾侧紧邻处刺激对侧内囊未能有效诱发EPSP。慢性半侧皮质切除并未改变完整对侧诱发的EPSP形状，但使其幅度降低约一半。这些观察结果表明，大鼠中对侧投射的皮质纹状体神经元在新纹状体中双向投射，有轴突分支至对侧大脑皮质以及新纹状体，并汇聚到也接受同侧相应皮质区域输入的新纹状体神经元上。
