Itoh M, Watanabe Y, Watanabe M, Tanaka K, Wada K, Takashima S
Department of Mental Retardation and Birth Defect Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan.
Brain Res. 1997 Sep 5;767(2):265-71. doi: 10.1016/s0006-8993(97)00572-6.
A glutamate transporter subtype, EAAT4, is closely related to removal of glutamate from the synaptic cleft. Immunohistochemistry for EAAT4 demonstrated the specific distribution and localization of its expression in the developing human cerebellum. Purkinje cells showed faint EAAT4 immunostaining at 17 gestational weeks (GW), which became increasingly intense from 23 GW to the infantile period. In the late fetal to early infantile periods, Purkinje cells showed marked immunoreactivity. After the late infantile period, EAAT4 immunoreactivity was the same in extent as in the adult pattern. Its intracellular localization also changed with development. EAAT4 immunoreactivity was demonstrated in the short processes of Purkinje cells in the early embryonic period, in the cell bodies and dendrites in the late fetal to early infantile periods, and then in the spines after the late infantile period. In the adult cerebellum, immunoreactivity was detected strongly in the spines of Purkinje cells and weakly in the cell bodies. No immunoreactivity was found in the axons or axon terminals of the cells. Thus, the glutamate transporter exhibits developmental changes in its distribution in the cerebellum and its localization in Purkinje cells. EAAT4 immunoreactivity may be related to the dendritic arborization of cells in the molecular layer.
一种谷氨酸转运体亚型，即兴奋性氨基酸转运体4（EAAT4），与从突触间隙清除谷氨酸密切相关。EAAT4的免疫组织化学显示了其在发育中的人类小脑中表达的特定分布和定位。浦肯野细胞在妊娠17周（GW）时显示出微弱的EAAT4免疫染色，从23周GW到婴儿期，这种染色变得越来越强烈。在胎儿晚期到婴儿早期，浦肯野细胞显示出明显的免疫反应性。婴儿晚期之后，EAAT4免疫反应性的程度与成人模式相同。其细胞内定位也随发育而变化。在胚胎早期，EAAT4免疫反应性在浦肯野细胞的短突起中显示，在胎儿晚期到婴儿早期在细胞体和树突中显示，然后在婴儿晚期之后在棘突中显示。在成人大脑中，在浦肯野细胞的棘突中检测到强烈的免疫反应性，在细胞体中检测到微弱的免疫反应性。在细胞的轴突或轴突终末未发现免疫反应性。因此，谷氨酸转运体在小脑中的分布及其在浦肯野细胞中的定位表现出发育变化。EAAT4免疫反应性可能与分子层中细胞的树突分支有关。
