Schmitt A, Asan E, Püschel B, Jöns T, Kugler P
Institute of Anatomy, University of Würzburg, Germany.
Neuroscience. 1996 Apr;71(4):989-1004. doi: 10.1016/0306-4522(95)00477-7.
Non-radioactive in situ hybridization using complementary RNA and oligonucleotide probes was applied in order to clearly identify the cell types expressing GLT1 and to show their regional distribution in the central nervous system of the rat. The results were compared with immunocytochemical data achieved using an antibody against a synthetic GLT1 peptide. The study showed that GLT1 was expressed in astrocytes and Bergmann glia which were identified by the detection of an astrocytic marker protein. Additionally, subsets of neurons in different brain regions (e.g., CA3/4 pyramidal cells of the hippocampus, endopiriform nucleus) were labelled by in situ hybridization. In other cell types of the central nervous system (oligodendrocytes, ependymal cells, epithelal cells of the choroid plexus, tanycytes), GLT1 expression was not detectable. The generally dense astrocytic immunolabelling of the gray matter of the brain showed an even higher intensity in regions reported to show high glutamatergic activity and astrocytic glutamate metabolism (e.g., the termination field of the glutamatergic perforant path in the hippocampus). On the basis of the cellular regional distribution of the GLT1 messenger RNA and protein demonstrated in the present study, it is reasonable to assume that this high affinity transporter is of importance for the maintenance of adequate extraneuronal glutamate levels.
为了清晰地鉴定表达GLT1的细胞类型并展示其在大鼠中枢神经系统中的区域分布，应用了使用互补RNA和寡核苷酸探针的非放射性原位杂交技术。将结果与使用抗合成GLT1肽的抗体获得的免疫细胞化学数据进行了比较。研究表明，GLT1在星形胶质细胞和伯格曼胶质细胞中表达，这些细胞通过检测星形胶质细胞标记蛋白得以鉴定。此外，不同脑区的神经元亚群（例如，海马体的CA3/4锥体细胞、内梨状核）通过原位杂交被标记。在中枢神经系统的其他细胞类型（少突胶质细胞、室管膜细胞、脉络丛上皮细胞、伸长细胞）中，未检测到GLT1表达。大脑灰质普遍密集的星形胶质细胞免疫标记在据报道显示高谷氨酸能活性和星形胶质细胞谷氨酸代谢的区域（例如，海马体中谷氨酸能穿通通路 的终末场）表现出更高的强度。基于本研究中证明的GLT1信使RNA和蛋白质的细胞区域分布，可以合理推测这种高亲和力转运体对于维持足够的细胞外谷氨酸水平很重要。
