Alvarez-Bolado G, Rodríguez-Sánchez P, Tejero-Díez P, Fairén A, Díez-Guerra F J
Instituto Cajal, CSIC, Madrid, Spain.
Neuroscience. 1996 Jul;73(2):565-80. doi: 10.1016/0306-4522(96)00061-9.
We have used a novel antibody to map the distribution of the protein kinase C substrate protein RC3/neurogranin during the development of the rat telencephalon. Neurogranin appearance in the rat brain is biphasic: it shows an early stage of anatomically restricted, low-intensity expression, and a juvenile stage of anatomically widespread, high-intensity expression. Most of the structures that express neurogranin during development conserve it in the adult stage. Neurogranin expression starts on embryonic day 18 in two different sites-the amygdalar primordium and in the piriform cortex-and is confined to these structures until the first postnatal day (P1). On P1, neurogranin expression increases dramatically in intensity, and appears in the olfactory cortex, isocortex, subiculum and hippocampus. In the striatum, expression starts on P1 and extends to the caudoputamen and parts of the globus pallidus and septum. Particularly complex patterns of labelling can be seen in the amygdala and cerebral cortex. Cortical layers showing early expression are the presumptive layers 4 and 5 in the somatosensory cortex, and layers 2 and 5 in the anterior cingulate and agranular insular cortices. Immunoreactivity is found mostly in cell bodies during the early and juvenile stages, but by the end of the first postnatal week it starts being more apparent in the neuropil. This phenomenon probably reflects the intracellular translocation of neurogranin to distal parts of the dendrites and dendritic spines. This process culminates by the end of the second postnatal week, when the adult pattern is reached. According to the timing and anatomy of its distribution, expression of neurogranin seems to be independently regulated in each telencephalic region by specific signalling mechanisms. It is proposed, on this basis, that neurogranin could be implicated in neuronal differentiation and synaptogenesis during telencephalic development.
我们使用了一种新型抗体来绘制蛋白激酶C底物蛋白RC3/神经颗粒素在大鼠端脑发育过程中的分布情况。神经颗粒素在大鼠脑中的出现呈双相性：它显示出一个解剖学上受限、低强度表达的早期阶段，以及一个解剖学上广泛、高强度表达的幼年阶段。在发育过程中表达神经颗粒素的大多数结构在成年阶段仍保留该表达。神经颗粒素的表达在胚胎第18天开始于两个不同部位——杏仁核原基和梨状皮质——并在出生后第一天（P1）之前局限于这些结构。在P1时，神经颗粒素的表达强度急剧增加，并出现在嗅觉皮质、同型皮质、海马下托和海马体中。在纹状体中，表达始于P1，并延伸至尾状壳核以及苍白球和隔区的部分区域。在杏仁核和大脑皮质中可以看到特别复杂的标记模式。早期表达的皮质层是体感皮质中的推测第4层和第5层，以及前扣带回和无颗粒岛叶皮质中的第2层和第5层。在早期和幼年阶段，免疫反应主要存在于细胞体中，但在出生后第一周结束时，它开始在神经毡中更明显。这种现象可能反映了神经颗粒素向树突和树突棘远端的细胞内转运。这个过程在出生后第二周结束时达到顶峰，此时形成成年模式。根据其分布的时间和解剖结构，神经颗粒素的表达似乎在每个端脑区域由特定的信号机制独立调节。在此基础上，有人提出神经颗粒素可能参与端脑发育过程中的神经元分化和突触形成。
