Van Groen T, Wyss J M
Department of Cell Biology, University of Alabama, Birmingham 35294, USA.
J Comp Neurol. 1995 Aug 7;358(4):584-604. doi: 10.1002/cne.903580411.
The present study characterized the projections of the anterodorsal (AD) and the anteroventral (AV) thalamic nuclei to the limbic cortex. Both AD and AV project to the full extent of the retrosplenial granular cortex in a topographic pattern. Neurons in caudal parts of both nuclei project to rostral retrosplenial cortex, and neurons in rostral parts of both nuclei project to caudal retrosplenial cortex. Within AV, the magnocellular neurons project primarily to the retrosplenial granular a cortex, whereas the parvicellular neurons project mainly to the retrosplenial granular b cortex. AD projections to retrosplenial cortex terminate in very different patterns than do AV projections: The AD projection terminates with equal density in layers I, III, and IV of the retrosplenial granular cortex, whereas, in contrast, the AV projections terminate very densely in layer Ia and less densely in layer IV. Further, both AD and AV project densely to the postsubicular, presubicular, and parasubicular cortices and lightly to the entorhinal (only the most caudal part) cortex and to the subiculum proper (only the most septal part). Rostral parts of AD project equally to all three subicular cortices, whereas neurons in caudal AD project primarily to the postsubicular cortex. Compared to AD, neurons in AV have a less extensive projection to the subicular cortex, and this projection terminates primarily in the postsubicular and presubicular cortices. Further, the AD projection terminates in layers I, II/III, and V of postsubiculum, whereas the AV projection terminates only in layers I and V.
本研究描述了丘脑前背核（AD）和前腹核（AV）向边缘皮质的投射。AD和AV均以拓扑模式投射至脾后颗粒皮质的整个范围。两个核尾侧部分的神经元投射至脾后皮质嘴侧，而两个核嘴侧部分的神经元投射至脾后皮质尾侧。在AV内，大细胞神经元主要投射至脾后颗粒a皮质，而小细胞神经元主要投射至脾后颗粒b皮质。AD向脾后皮质的投射终止模式与AV投射截然不同：AD投射在脾后颗粒皮质的I、III和IV层以相等密度终止，而相比之下，AV投射在Ia层非常密集地终止，在IV层则较稀疏。此外，AD和AV均密集投射至后下托、前下托和旁下托皮质，而向内嗅皮质（仅最尾侧部分）和下托本身（仅最隔区部分）的投射较稀疏。AD嘴侧部分向所有三个下托皮质的投射均等，而AD尾侧的神经元主要投射至后下托皮质。与AD相比，AV中的神经元向下托皮质的投射范围较小，且该投射主要终止于后下托和前下托皮质。此外，AD投射终止于后下托的I、II/III和V层，而AV投射仅终止于I层和V层。
