Semi-quantitative distribution of excitatory amino acid (glutamate) transporters 1-3 (EAAT1-3) and the cystine-glutamate exchanger (xCT) in the adult murine spinal cord, Neurochem Int, 2020.(IF: 4.4)

Abstract: This study investigates the distribution of glutamate transporters EAAT1-3 and the glutamate-cystine exchanger (xCT) in the spinal cord. The findings reveal that EAAT2 and EAAT3 are uniformly expressed across all gray matter regions, with slightly higher levels in laminae 1-4. EAAT2 also exhibits higher expression in lamina 9, while EAAT3 is detected in the lateral spinal nucleus. EAAT1 is predominantly concentrated in the dorsal horn laminae 1-3, lamina 10, the intermediolateral nucleus, and the sacral parasympathetic nucleus. xCT is mainly concentrated in the dorsal horn laminae 1-3, lamina 10, and the leptomeninges. Quantitative immunoblotting analysis indicates that the average level of EAAT1 in the entire spinal cord is 0.6% of that in the cerebellum, while the levels of EAAT2, EAAT3, and xCT are 41.6%, 39.8%, and 30.8% of the levels in the hippocampus, respectively. Given that the hippocampal content of EAAT2 protein is two orders of magnitude higher than that of EAAT3, it follows that most of the gray matter in the spinal cord relies almost exclusively on EAAT2 for glutamate removal, whereas the laminae involved in the processing of autonomic and nociceptive information depend on a complex system of transporters.

摘要：本文研究了脊髓中谷氨酸转运蛋白EAAT1-3和谷氨酸-半胱氨酸交换器（xCT）的分布情况。研究发现：EAAT2和EAAT3在所有灰质区域均匀表达，但在laminae 1-4的表达略高。EAAT2在lamina 的表达也较高，而EAAT3在侧脊髓核也有检测到。EAAT1主要集中在背角的laminae 1-3、lamina 10、内侧外侧核和骶副交感核。xCT主要集中在背角的laminae 1-3、lamina 10和软脑膜。定量免疫印迹分析显示，整个脊髓中EAAT1的平均水平是小脑中的0.6%，而EAAT2、EAAT3和xCT的水平分别是海马体中的41.6%、39.8%和30.8%。由于海马体中EAAT2蛋白的含量比EAAT3高两个数量级，因此脊髓中的大部分灰质几乎完全依赖EAAT2来清除谷氨酸。