Hazrati L N, Parent A
Centre de recherche en neurobiologie, Université Laval et Hôpital de l'Enfant-Jésus, Qué., Canada.
Brain Res. 1992 Dec 11;598(1-2):311-5. doi: 10.1016/0006-8993(92)90199-j.
Double-anterograde tract-tracing experiments in the squirrel monkey (Saimiri sciureus) reveal that fibers from the striatum and the subthalamic nucleus converge onto the same neurons in both the external (GPe) and internal (GPi) segments of the globus pallidus. However, these two pallidal afferents arborize according to a different pattern in GPe and GPi. Whereas the striatal fibers closely entwined the distal dendrites of pallidal neurons in a similar fashion in both pallidal segments, the subthalamic fibers display a tight pericellular arrangement that is much more obvious in GPi than in GPe. This perisomatic arborization is similar to the pericellular contacts made by the GPe fibers terminating on GPi neurons. Such a resemblance suggests that these two types of afferents exert an opposite effect upon the cell body and proximal dendrites of GPi neurons. It also raises the possibility for striatal neurons to influence the same GPi neuron by acting directly on its distal dendrites and indirectly on its cell body via a relay in GPe.
松鼠猴（Saimiri sciureus）的双顺行束路追踪实验表明，来自纹状体和丘脑底核的纤维汇聚到苍白球外部（GPe）和内部（GPi）节段的同一神经元上。然而，这两种苍白球传入纤维在GPe和GPi中的分支模式不同。在两个苍白球节段中，纹状体纤维都以类似的方式紧密缠绕在苍白球神经元的远端树突上，而丘脑底核纤维则呈现紧密的细胞周排列，这种排列在GPi中比在GPe中更为明显。这种胞体周围分支类似于终止于GPi神经元上的GPe纤维形成的细胞周接触。这种相似性表明，这两种传入纤维对GPi神经元的细胞体和近端树突产生相反的作用。这也增加了纹状体神经元通过直接作用于其远端树突并通过GPe中的中继间接作用于其细胞体来影响同一GPi神经元的可能性。
