Mitrovic A D, Johnston G A
Department of Pharmacology, University of Sydney, NSW, Australia.
Neurochem Int. 1994 Jun;24(6):583-8. doi: 10.1016/0197-0186(94)90011-6.
The sodium-dependent high affinity transport of L-[3H]glutamate and L-[3H]aspartate into synaptosomal fractions prepared from three different regions was employed to investigate the inhibitors L-trans-pyrrolidine-2,4-dicarboxylate, threo-3-hydroxy-D-aspartate and D-aspartate. These substances showed regional heterogeneity as inhibitors of sodium-dependent high affinity uptake of L-glutamate and L-aspartate. L-trans-Pyrrolidine-2,4-dicarboxylate was a more potent inhibitor of the uptake of L-glutamate than of L-aspartate in the cortex (IC50 8 microM vs L-glutamate and 13 microM vs L-aspartate) and cerebellum (IC50 4 microM v L-glutamate and 8 microM vs L-aspartate). threo-3-Hydroxy-D-aspartate was a more potent inhibitor of the uptake of L-glutamate than of L-aspartate in the cortex (IC50 9 microM vs L-glutamate and 13 microM vs L-aspartate) and hippocampus (IC50 6 microM v L-glutamate and 11 microM v L-aspartate). D-Aspartate was a more potent inhibitor of the uptake of L-glutamate than of L-aspartate only in the cortex (IC50 8 microM vs L-glutamate and 15 microM vs L-aspartate). These results thus support other evidence that there is regional heterogeneity in sodium-dependent high affinity acidic amino acid uptake sites in the brain.
利用L-[3H]谷氨酸和L-[3H]天冬氨酸的钠依赖性高亲和力转运进入从三个不同区域制备的突触体组分，来研究抑制剂L-反式吡咯烷-2,4-二羧酸、苏式-3-羟基-D-天冬氨酸和D-天冬氨酸。这些物质作为L-谷氨酸和L-天冬氨酸钠依赖性高亲和力摄取的抑制剂表现出区域异质性。L-反式吡咯烷-2,4-二羧酸在皮质（L-谷氨酸的IC50为8 microM，L-天冬氨酸的IC50为13 microM）和小脑（L-谷氨酸的IC50为4 microM，L-天冬氨酸的IC50为8 microM）中对L-谷氨酸摄取的抑制作用比对L-天冬氨酸更强。苏式-3-羟基-D-天冬氨酸在皮质（L-谷氨酸的IC50为9 microM，L-天冬氨酸的IC50为13 microM）和海马体（L-谷氨酸的IC50为6 microM，L-天冬氨酸的IC50为11 microM）中对L-谷氨酸摄取的抑制作用比对L-天冬氨酸更强。D-天冬氨酸仅在皮质中对L-谷氨酸摄取的抑制作用比对L-天冬氨酸更强（L-谷氨酸的IC50为8 microM，L-天冬氨酸的IC50为15 microM）。因此，这些结果支持了其他证据，即大脑中钠依赖性高亲和力酸性氨基酸摄取位点存在区域异质性。
