A dynamic switch between inhibitory and excitatory currents in a neuronal glutamate transporter.
A dynamic switch between inhibitory and excitatory currents in a neuronal glutamate transporter.
复制标题
神经元谷氨酸转运蛋白中抑制性电流和兴奋性电流之间的动态切换。
DOI：
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发表时间：
2005
影响因子：
11.1
通讯作者：
C. Fahlke
中科院分区：
文献类型：
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作者：
Nico Melzer;Delany Torres;C. Fahlke
兴奋性氨基酸转运蛋白（EAAT）终止谷氨酸能突触传递，并将中枢神经系统中的细胞外谷氨酸浓度维持在兴奋性毒性水平以下。除了维持次级活性谷氨酸转运之外，EAAT 谷氨酸转运蛋白还充当阴离子选择性通道。在这里，我们报告了一个门控过程，该过程使与神经元谷氨酸转运蛋白 EAAT4 相关的阴离子通道对阳离子具有渗透性，并导致在实际电流反转电位为负的电压下选择性增加开放概率。激活过程取决于膜电位和细胞外谷氨酸浓度，并导致 EAAT4 阴离子通道积聚在有利于阳离子流入和阴离子流出的状态。因此，EAAT4 阴离子通道的门控允许在静息细胞中的抑制电流和电活性细胞中的兴奋电流之间进行切换。这种转运蛋白介导的电导可以改变浦肯野神经元的兴奋性，为它们提供前所未有的适应机制。
Excitatory amino acid transporters (EAATs) terminate glutamatergic synaptic transmission and maintain extracellular glutamate concentrations in the central nervous system below excitotoxic levels. In addition to sustaining a secondary-active glutamate transport, EAAT glutamate transporters also function as anion-selective channels. Here, we report a gating process that makes anion channels associated with a neuronal glutamate transporter, EAAT4, permeable to cations and causes a selective increase of the open probability at voltages negative to the actual current reversal potential. The activation process depends on both membrane potential and extracellular glutamate concentration and causes an accumulation of EAAT4 anion channels in a state favoring cation influx and anion efflux. Gating of EAAT4 anion channels thus allows a switch between inhibitory currents in resting cells and excitatory currents in electrically active cells. This transporter-mediated conductance could modify the excitability of Purkinje neurons, providing them with an unprecedented mechanism for adaptation.
光感受器中谷氨酸激活电流的噪声分析。
DOI：
10.1016/s0006-3495(96)79613-3
发表时间：
1996
期刊：
Biophysical journal.
影响因子：
--
作者：
Larsson,HP;Picaud,SA;Werblin,FS;Lecar,H
通讯作者：
Lecar,H