PDF(Pubmed)
Abstract：
We used diverse methods to characterize the role of avian lateral spiriform nucleus (SpL) in basal ganglia motor function. Connectivity analysis showed that SpL receives input from globus pallidus (GP), and the intrapeduncular nucleus (INP) located ventromedial to GP, whose neurons express numerous striatal markers. SpL-projecting GP neurons were large and aspiny, while SpL-projecting INP neurons were medium sized and spiny. Connectivity analysis further showed that SpL receives inputs from subthalamic nucleus (STN) and substantia nigra pars reticulata (SNr), and that the SNr also receives inputs from GP, INP, and STN. Neurochemical analysis showed that SpL neurons express ENK, GAD, and a variety of pallidal neuron markers, and receive GABAergic terminals, some of which also contain DARPP32, consistent with GP pallidal and INP striatal inputs. Connectivity and neurochemical analysis showed that the SpL input to tectum prominently ends on GABAA receptor-enriched tectobulbar neurons. Behavioral studies showed that lesions of SpL impair visuomotor behaviors involving tracking and pecking moving targets. Our results suggest that SpL modulates brainstem-projecting tectobulbar neurons in a manner comparable to the demonstrated influence of GP internus on motor thalamus and of SNr on tectobulbar neurons in mammals. Given published data in amphibians and reptiles, it seems likely the SpL circuit represents a major direct pathway-type circuit by which the basal ganglia exerts its motor influence in nonmammalian tetrapods. The present studies also show that avian striatum is divided into three spatially segregated territories with differing connectivity, a medial striato-nigral territory, a dorsolateral striato-GP territory, and the ventrolateral INP motor territory.
摘要：
我们使用多种方法来表征鸟类外侧螺旋状核（SpL）在基底神经节运动功能中的作用。连通性分析表明，SpL接收来自苍白球(GP)的输入，和位于GP腹内侧的胞内核（INP），其神经元表达许多纹状体标记。SpL投射的GP神经元大而长，而SpL投射INP神经元大小中等，呈多刺。连通性分析进一步显示，SpL接收来自丘脑底核（STN）和黑质网状膜（SNr）的输入，并且SNr还从GP接收输入，INP,和STN。神经化学分析显示SpL神经元表达ENK,GAD,和各种苍白神经元标记，并接受GABA能终端，其中一些还含有DARPP32，与GP苍白球和INP纹状体输入一致。连接性和神经化学分析表明，SpL输入到顶骨的显着终止于富含GABAA受体的顶球神经元。行为研究表明，SpL的病变会损害涉及跟踪和啄食运动目标的视觉运动行为。我们的结果表明，SpL以与已证明的GP内部对哺乳动物的运动丘脑和SNr对构造球神经元的影响相当的方式调节脑干投射球神经元。鉴于两栖动物和爬行动物的公开数据，SpL回路似乎代表了主要的直接途径型回路，基底神经节通过该回路在非哺乳动物四足动物中发挥其运动影响。本研究还表明，鸟类纹状体分为三个空间隔离的区域，具有不同的连通性，内侧纹状体-黑色区域，背外侧纹状体-GP区，和腹侧INP运动区域。
