Sadikot A F, Parent A, François C
Centre de Recherche en Neurobiologie, Université Laval et Hôpital de l'Enfant-Jésus, Québec, Canada.
J Comp Neurol. 1992 Jan 8;315(2):137-59. doi: 10.1002/cne.903150203.
The subcortical projections of the centromedian (CM) and the parafascicular (Pf) thalamic nuclei were examined in the squirrel monkey (Saimiri sciureus) by using the lectin Phaseolus vulgaris-leucoagglutinin (PHA-L) as an anterograde tracer. Both CM and Pf project massively to the striatum where they arborize in a complementary fashion. On the one hand, CM innervates most of the putamen caudal to the anterior commissure, a dorsolateral rim of the putamen rostral to the anterior commissure, discrete areas of the head of the caudate nucleus close to the internal capsule, and a lateral sector of the body of the caudate nucleus. On the other hand, Pf provides a heavy input to the head, body, and tail of the caudate nucleus, and to the rostral putamen, excluding the areas innervated by CM. In addition, Pf projects more discretely to the nucleus accumbens and the olfactory tubercle. Therefore, the projections from both CM and Pf cover the entire striatum, with those from CM arborizing into the "sensorimotor" striatal territory and the ones from Pf innervating the "associative-limbic" striatal territory. Furthermore, CM and Pf project to extrastriatal subcortical structures, such as the globus pallidus, the subthalamic nucleus, and the substantia nigra, where they also terminate in a complementary fashion. Topographically and cytologically, Pf is closely related to the subparafascicular nucleus (sPf). The Pf-sPf complex projects to the hypothalamus, the substantia innominata, the peripeduncular nucleus, and the amygdala. It also gives rise to descending efferents arborizing in various brainstem structures, including the inferior olivary complex. Additional studies with retrograde double-labeling methods show that distinct cell groups within CM project to the motor cortex and the striatum. Likewise, separate neuronal populations within the CM-Pf-sPf complex give rise to striatal and brainstem projections, the former arising from CM and Pf and the latter mainly from sPf. The complementary nature of CM and Pf projections to the striatum and other basal ganglia components suggests that this thalamic complex participates in a highly ordered manner in the parallel processing of the information that flows through the basal ganglia.
通过使用凝集素菜豆白细胞凝集素（PHA-L）作为顺行示踪剂，在松鼠猴（Saimiri sciureus）中研究了中央中核（CM）和束旁核（Pf）的丘脑皮质下投射。CM和Pf都大量投射到纹状体，它们在纹状体中以互补的方式分支。一方面，CM支配前连合尾侧的大部分壳核、前连合嘴侧壳核的背外侧边缘、靠近内囊的尾状核头部的离散区域以及尾状核体的外侧部分。另一方面，Pf向尾状核的头部、体部和尾部以及嘴侧壳核提供大量输入，但不包括CM支配的区域。此外，Pf更离散地投射到伏隔核和嗅结节。因此，CM和Pf的投射覆盖了整个纹状体，CM的投射分支到“感觉运动”纹状体区域，Pf的投射支配“联合-边缘”纹状体区域。此外，CM和Pf投射到纹状体以外的皮质下结构，如苍白球、丘脑底核和黑质，它们在这些结构中也以互补的方式终止。在拓扑学和细胞学上，Pf与束旁下核（sPf）密切相关。Pf-sPf复合体投射到下丘脑、无名质、脚周核和杏仁核。它还产生下行传出纤维，在包括下橄榄复合体在内的各种脑干结构中分支。逆行双重标记方法的进一步研究表明，CM内不同的细胞群投射到运动皮层和纹状体。同样，CM-Pf-sPf复合体内不同的神经元群体产生纹状体和脑干投射，前者来自CM和Pf，后者主要来自sPf。CM和Pf对纹状体及其他基底神经节成分的投射的互补性质表明，这个丘脑复合体以高度有序的方式参与流经基底神经节的信息的并行处理。
