Haber S N, Lynd-Balta E, Mitchell S J
Department of Neurobiology and Anatomy, University of Rochester School of Medicine, New York 14642.
J Comp Neurol. 1993 Mar 1;329(1):111-28. doi: 10.1002/cne.903290108.
This study describes the organization and topography of the descending efferent projections from the monkey ventral pallidum. The main efferent projections from the globus pallidus are to the subthalamus, to the thalamus, and to the substantia nigra. Although these projections have been well established for the dorsal pallidum, the projections of the ventral pallidum have not been explored in primates. The results of this study add an important link in how information from the limbic lobe is channeled through the basal ganglia in monkeys. Anterograde tracers, Phaseolus vulgaris-leucoagglutinin, and tritiated amino acids were injected into various regions of the ventral pallidum. The descending efferent projection from the ventral pallidum in monkeys terminates primarily in the subthalamic nucleus and adjacent lateral hypothalamus, in the substantia nigra, and in the lateral habenular nucleus. Although terminals are also found in the thalamus, these are relatively sparse. The projections to the subthalamic nucleus and the lateral hypothalamus are topographically arranged, while those to the substantia nigra are not. These results suggest that pathways from distinct pallidal regions that receive specific striatal input terminate in distinct regions of the subthalamic/hypothalamic regions, thus maintaining a topographic arrangement. Projections to the substantia nigra, however, overlap extensively, suggesting convergence of terminals from different ventral pallidal regions. The relatively small projection to the thalamus raises the question that without a prominent thalamic projection, is this system parallel to that described for the dorsal globus pallidus?
本研究描述了猴腹侧苍白球下行传出投射的组织和拓扑结构。苍白球的主要传出投射是到丘脑底核、丘脑和黑质。虽然这些投射在背侧苍白球中已得到充分证实，但灵长类动物腹侧苍白球的投射尚未被研究。本研究结果为边缘叶的信息如何通过猴的基底神经节传导增加了一个重要环节。将顺行示踪剂、菜豆白细胞凝集素和氚标记氨基酸注入腹侧苍白球的不同区域。猴腹侧苍白球的下行传出投射主要终止于丘脑底核和相邻的外侧下丘脑、黑质以及外侧缰核。虽然在丘脑中也发现了终末，但相对较少。投射到丘脑底核和外侧下丘脑的是按拓扑结构排列的，而投射到黑质的则不是。这些结果表明，来自接受特定纹状体输入的不同苍白球区域的通路终止于丘脑底核/下丘脑区域的不同区域，从而保持拓扑结构排列。然而，投射到黑质的区域广泛重叠，表明来自不同腹侧苍白球区域的终末会聚。向丘脑的投射相对较少，这就提出了一个问题：在没有明显丘脑投射的情况下，这个系统是否与背侧苍白球所描述的系统平行？
