Donovan M K, Wyss J M
Brain Res. 1983 Jan 24;259(2):181-92. doi: 10.1016/0006-8993(83)91249-0.
The present study has used the fluorescent dye tracing technique in order to determine the exact location of neuronal somata within the subicular cortex which project to the diencephalon, telencephalon (entorhinal cortex), or to both via axonal collaterals. The greatest collateralization to the two sites is found in the neurons of the subiculum proper. In this region approximately one-third of all neurons project to both the entorhinal cortex and the hypothalamus (either the mammillary bodies or the ventral medial hypothalamic nucleus). The hypothalamic and cortical projection cell bodies in this region are intermingled extensively with each other. In the cytoarchitectonically more organized regions of the subicular cortex, i.e. the pre-, para- and postsubiculum, the situation is quite different. In these areas neurons project to the hypothalamus or entorhinal cortex but very seldom does a single neuron project to both areas, and the neuronal somata are spatially segregated according to their projections. The entorhinal cortex projecting somata are located in layer two whereas the hypothalamic neurons are in the deeper layer. The somata projecting to the thalamus are the most deeply located neurons in all regions of the subicular cortex, and extremely few collateralize to the entorhinal cortex.
本研究采用荧光染料追踪技术，以确定海马下托皮质内投射至间脑、端脑（内嗅皮质）或通过轴突侧支同时投射至两者的神经元胞体的确切位置。在海马下托本身的神经元中发现向这两个部位发出侧支的情况最为明显。在该区域，所有神经元中约有三分之一同时投射至内嗅皮质和下丘脑（乳头体或下丘脑腹内侧核）。该区域下丘脑和皮质投射细胞体彼此广泛交织。在海马下托皮质细胞构筑更有组织的区域，即前下托、旁下托和后下托，情况则大不相同。在这些区域，神经元投射至下丘脑或内嗅皮质，但很少有单个神经元同时投射至这两个区域，并且神经元胞体根据其投射在空间上是分开的。投射至内嗅皮质的胞体位于第二层，而下丘脑神经元位于较深层。投射至丘脑的胞体是海马下托皮质所有区域中位置最深的神经元，极少有侧支投射至内嗅皮质。
