Saitoh S, Takamatsu K, Kobayashi M, Noguchi T
Department of Physiology, Toho University School of Medicine, Tokyo, Japan.
Brain Res Dev Brain Res. 1994 Jul 15;80(1-2):199-208. doi: 10.1016/0165-3806(94)90105-8.
Expression of hippocalcin in the developing rat brain was investigated by a combination of Northern blot, in situ hybridization, immunoblot and immunohistochemical methods. In the hippocampus, hippocalcin mRNA and immunoreactivity first appeared in the CA3 pyramidal cells on embryonic day 19 (E19) and postnatal day 1 (P1), respectively, and extended throughout Ammon's horn. After P14, the hippocampal pyramidal cells, especially in the CA1 region, maintained the highest expression level among the brain regions. The dentate granule cells expressed a small amount of hippocalcin mRNA and immunoreactivity from P7 and maintained a low level through the developmental stages. In the cerebral cortex, hippocalcin mRNA and immunoreactivity appeared in the pyramidal cells of the piriform cortex from P1 and P4, respectively. Their expression extended throughout the cerebral cortex and reached the maximum level on P14, and then declined gradually with age to half of the maximum level by adults. In the cerebellum, a few Purkinje cells expressed a small amount of hippocalcin mRNA and immunoreactivity on P7. Their expression became evident in most of the Purkinje cells on P14 and increased gradually by P28. Then, their expression declined with age; however, the immunoreactivity was concentrated in the cell bodies and proximal segments of the dendrites in adults. These results suggest that the expression of hippocalcin mRNA and protein is strictly controlled by both the cell type and the developmental process and that hippocalcin plays a role in neuronal differentiation in the early stages of development and may relate to other neuronal function in the adult brain.
采用Northern印迹法、原位杂交法、免疫印迹法和免疫组织化学法相结合的方法，研究了海马钙蛋白在发育中的大鼠大脑中的表达情况。在海马中，海马钙蛋白mRNA和免疫反应性分别在胚胎第19天（E19）和出生后第1天（P1）首次出现在CA3锥体细胞中，并延伸至整个海马角。P14后，海马锥体细胞，尤其是CA1区的锥体细胞，在脑区中保持最高表达水平。齿状颗粒细胞从P7开始表达少量海马钙蛋白mRNA和免疫反应性，并在整个发育阶段维持低水平。在大脑皮层，海马钙蛋白mRNA和免疫反应性分别在P1和P4时出现在梨状皮层的锥体细胞中。它们的表达延伸至整个大脑皮层，并在P14达到最高水平，然后随着年龄的增长逐渐下降，到成年时降至最高水平的一半。在小脑中，少数浦肯野细胞在P7时表达少量海马钙蛋白mRNA和免疫反应性。它们的表达在P14时在大多数浦肯野细胞中变得明显，并在P28时逐渐增加。然后，它们的表达随着年龄的增长而下降；然而，在成年个体中，免疫反应性集中在细胞体和树突的近端节段。这些结果表明，海马钙蛋白mRNA和蛋白质的表达受到细胞类型和发育过程的严格控制，并且海马钙蛋白在发育早期的神经元分化中起作用，并且可能与成年大脑中的其他神经元功能有关。
