Lund R D, Mustari M J
J Comp Neurol. 1977 May 15;173(2):289-306. doi: 10.1002/cne.901730206.
Most cell of the dorsal laterial geniculate nucleus of rats are generated on fetal days 12 to 14. Their axons invade the telencephalon on fetal day 16 and run in the intermediate zone just below the cortical plate, reaching the visual area of fetal day 18. The axons do not invade the cortical plate significantly until close to birth (day 22 of gestation) and reach their zone of terminal distribution between postnatal days 1 and 4. In subsequent days the projection becomes progressively more heavily distrubuted in layers IV and I, and synapses of thalamic origin can be identified in these layers. While cells destined for layers IV cross the intermediate zone at the time that thalamic axons first arrive, this coincidence of growth does not seem to be a factor which determines the specificity of patterns of thalamocortical connections since the cells reach layer IV several days before the axons. It is unclear why the axons should wait several days in the region immediately below the cortical plate before invading; although there is a parallel in previous studies on the development of the chick retinotectal pathway (Crossland et al., '75).
大鼠外侧膝状体核的大多数细胞在胚胎第12至14天产生。它们的轴突在胚胎第16天侵入端脑，并在皮质板下方的中间带中延伸，在胚胎第18天到达视觉区。轴突直到接近出生（妊娠第22天）才大量侵入皮质板，并在出生后第1至4天到达其终末分布区。在随后的几天里，投射在IV层和I层中的分布逐渐变得更加密集，并且可以在这些层中识别出丘脑起源的突触。虽然注定要进入IV层的细胞在丘脑轴突首次到达时穿过中间带，但这种生长的巧合似乎并不是决定丘脑皮质连接模式特异性的因素，因为这些细胞在轴突到达前几天就到达了IV层。目前尚不清楚为什么轴突在侵入皮质板之前要在其下方的区域等待几天；尽管在先前关于鸡视网膜顶盖通路发育的研究中有类似情况（克罗斯兰等人，1975年）。
