L-[35S]半胱磺酸可选择性检测突触膜中氯离子依赖性L-谷氨酸转运体。

L-[35S]cysteic acid selectively detects chloride-dependent L-glutamate transporters in synaptic membrane.

作者信息

Koyama Y, Baba A, Iwata H

机构信息

Department of Pharmacology, Faculty of Pharmaceutical Sciences, Osaka University, Suita, Japan.

出版信息

Brain Res. 1989 May 15;487(1):113-9. doi: 10.1016/0006-8993(89)90946-3.

DOI:10.1016/0006-8993(89)90946-3

PMID:2568869

Abstract

Na+-independent L-[35S]cysteic acid (CA) accumulation in rat cortical synaptic membrane was examined. In the absence of Cl-, the accumulation was not observed. Addition of Cl- revealed the accumulation in a dose-dependent manner. Br- and NO3- also did. Ca2+-enhanced the Cl- -dependent accumulation, whereas low concentrations of Na+ reduced it. L-[35S]CA accumulation was inhibited by quisqualate, L-glutamate (L-Glu), L-cysteine sulfinate, D,L-homocysteic acid and D,L-2-amino-4-phosphonobutyrate (D,L-APB) potently. L-CA inhibited L-[3H]Glu accumulation in synaptic membrane in the presence of Cl-. The maximal inhibition of L-CA was equal to that of D,L-APB, but L-CA did not inhibit L-[3H]Glu accumulation in the absence of Cl-. These results show that L-[35S]CA selectively detects the Cl- -dependent L-Glu transporters in synaptic membrane.

摘要

研究了大鼠皮质突触膜中不依赖钠离子的L-[³⁵S]半胱磺酸（CA）积累情况。在无氯离子的情况下，未观察到积累现象。添加氯离子后，积累呈剂量依赖性。溴离子和硝酸根离子也有此现象。钙离子增强了依赖氯离子的积累，而低浓度钠离子则降低了积累。L-[³⁵S]CA积累受到quisqualate、L-谷氨酸（L-Glu）、L-半胱氨酸亚磺酸盐、D,L-高半胱氨酸和D,L-2-氨基-4-膦酸丁酸（D,L-APB）的强烈抑制。在有氯离子存在的情况下，L-CA抑制突触膜中L-[³H]Glu的积累。L-CA的最大抑制作用与D,L-APB相当，但在无氯离子的情况下，L-CA不抑制L-[³H]Glu的积累。这些结果表明，L-[³⁵S]CA能选择性地检测突触膜中依赖氯离子的L-Glu转运体。