Glutamate, the main excitatory neurotransmitter of the vertebrate central nervous system (CNS), is well known as a regulator of neuronal plasticity and neurodevelopment. Such glutamate function is thought to be mediated primarily by signaling through glutamate receptors. Thus, it requires a tight regulation of extracellular glutamate levels and a fine-tuned homeostasis that, when dysregulated, has been associated with a wide range of central pathologies including neuropsychiatric, neurodevelopmental, and neurodegenerative disorders. In the mammalian CNS, extracellular glutamate levels are controlled by a family of sodium-dependent glutamate transporters belonging to the solute carrier family 1 (SLC1) that are also referred to as excitatory amino acid transporters (EAATs). The presumed main function of EAATs has been best described in the context of synaptic transmission where EAATs expressed by astrocytes and neurons effectively regulate extracellular glutamate levels so that synapses can function independently. There is, however, increasing evidence that EAATs are expressed by cells other than astrocytes and neurons, and that they exhibit functions beyond glutamate clearance. In this review, we will focus on the expression and functions of EAATs in the myelinating cells of the CNS, oligodendrocytes. More specifically, we will discuss potential roles of oligodendrocyte-expressed EAATs in contributing to extracellular glutamate homeostasis, and in regulating oligodendrocyte maturation and CNS myelination by exerting signaling functions that have traditionally been associated with glutamate receptors. In addition, we will provide some examples for how dysregulation of oligodendrocyte-expressed EAATs may be involved in the pathophysiology of neurologic diseases.

中文翻译：

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谷氨酸转运蛋白：少突胶质细胞的表达和功能。

谷氨酸是脊椎动物中枢神经系统（CNS）的主要兴奋性神经递质，众所周知是神经元可塑性和神经发育的调节剂。认为这种谷氨酸功能主要是通过谷氨酸受体的信号传导来介导的。因此，它需要严格调节细胞外谷氨酸水平和微调的稳态，当失调时，其与广泛的中央病理学有关，包括神经精神病，神经发育和神经退行性疾病。在哺乳动物的中枢神经系统中，细胞外谷氨酸水平由属于溶质载体家族1（SLC1）的钠依赖性谷氨酸转运蛋白家族控制，该家族也称为兴奋性氨基酸转运蛋白（EAAT）。推测的EAAT的主要功能在突触传递的背景下得到了最好的描述，其中星形胶质细胞和神经元表达的EAAT有效调节细胞外谷氨酸水平，使突触可以独立发挥功能。但是，越来越多的证据表明，EAATs由星形胶质细胞和神经元以外的细胞表达，并且它们具有除谷氨酸清除以外的功能。在这篇综述中，我们将专注于EAAT在CNS少突胶质细胞的有髓细胞中的表达和功能。更具体地说，我们将讨论表达少突胶质细胞的EAAT在促进细胞外谷氨酸稳态，以及通过发挥传统上与谷氨酸受体相关的信号传导功能来调节少突胶质细胞成熟和CNS髓鞘形成的潜在作用。此外，