Meinecke D L, Rakic P
Section of Neurobiology, Yale University School of Medicine, New Haven, CT 06510.
Neuroscience. 1993 May;54(1):105-16. doi: 10.1016/0306-4522(93)90386-t.
Monoclonal antibodies against the low-affinity (p75) subunit of the human nerve growth factor receptor have been used to determine the temporal appearance of this receptor and to identify the associated cellular elements in the developing occipital cortex of rhesus monkeys. Adult and fetal brains from embryos at embryonic days 45-121 were used. This embryonic time span includes periods of active neurogenesis, cell migration and initial formation of axonal connections in the cerebral cortex. The first immunolabeling in the developing cerebral wall was seen between embryonic days 56 and 64. The labeling was present in the transient subplate neurons, a small number of axonal processes and pericytes associated with blood vessels. By birth, labeled neurons of the subplate zone disappeared, but immunolabeled axonal processes could now be seen in large numbers in the cortex. These findings are consistent with the role of nerve growth factor in the coordination of cortical differentiation, but not with the initiation of neuronal proliferation, since the emergence of nerve growth factor receptor-labeled elements in the cortex occurs two to three weeks after the onset of neurogenesis in this species. Further, the diverse cellular elements labeled in the fetal cerebrum with the antibodies to the low-affinity nerve growth factor receptor suggests that a receptor or receptors associated with growth factor signaling for more than one growth factor family are recognized by these antibodies. Differential timing in the expression of families of growth factor receptors may be one mechanism by which developing neurons in the cerebral cortex could respond to the different signals which guide such processes as synaptogenesis and morphogenesis.
针对人类神经生长因子受体低亲和力（p75）亚基的单克隆抗体已被用于确定该受体的出现时间，并识别恒河猴发育中的枕叶皮质中相关的细胞成分。使用了来自胚胎第45至121天的成年和胎儿大脑。这个胚胎时间跨度包括大脑皮质中活跃的神经发生、细胞迁移和轴突连接初步形成的时期。在发育中的脑壁中首次免疫标记出现在胚胎第56至64天之间。标记出现在短暂的板下层神经元、少量轴突和与血管相关的周细胞中。出生时，板下层区域的标记神经元消失，但现在可以在皮质中大量看到免疫标记的轴突。这些发现与神经生长因子在皮质分化协调中的作用一致，但与神经元增殖的启动不一致，因为在该物种中，皮质中神经生长因子受体标记元素的出现发生在神经发生开始后的两到三周。此外，用针对低亲和力神经生长因子受体的抗体在胎儿大脑中标记的多种细胞成分表明，这些抗体识别与一个以上生长因子家族的生长因子信号相关的一种或多种受体。生长因子受体家族表达的不同时间可能是大脑皮质中发育中的神经元对指导突触发生和形态发生等过程的不同信号作出反应的一种机制。
