CNS Research Group, Department of Pharmacology and Physiology, Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada.
Department of Psychiatry, Faculty of Medicine, Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada.
Front Neural Circuits. 2018 Dec 18;12:113. doi: 10.3389/fncir.2018.00113. eCollection 2018.
Multiple discoveries made since the identification of vesicular glutamate transporters (VGLUTs) two decades ago revealed that many neuronal populations in the brain use glutamate in addition to their "primary" neurotransmitter. Such a mode of cotransmission has been detected in dopamine (DA), acetylcholine (ACh), serotonin (5-HT), norepinephrine (NE) and surprisingly even in GABA neurons. Interestingly, work performed by multiple groups during the past decade suggests that the use of glutamate as a cotransmitter takes different forms in these different populations of neurons. In the present review, we will provide an overview of glutamate cotransmission in these different classes of neurons, highlighting puzzling differences in: (1) the proportion of such neurons expressing a VGLUT in different brain regions and at different stages of development; (2) the sub-cellular localization of the VGLUT; (3) the localization of the VGLUT in relation to the neurons' other vesicular transporter; and (4) the functional role of glutamate cotransmission.
二十年前囊泡谷氨酸转运体（VGLUTs）被鉴定以来，已经有多项发现揭示了大脑中的许多神经元群体除了其“主要”神经递质外还使用谷氨酸。这种共传递模式已经在多巴胺（DA）、乙酰胆碱（ACh）、血清素（5-HT）、去甲肾上腺素（NE）中被检测到，甚至在 GABA 神经元中也令人惊讶地被检测到。有趣的是，过去十年中多个研究小组的工作表明，谷氨酸作为共递质在这些不同神经元群体中的使用形式不同。在本综述中，我们将概述这些不同类型神经元中的谷氨酸共传递，突出显示在以下方面存在令人费解的差异：（1）在不同脑区和不同发育阶段表达 VGLUT 的这类神经元的比例；（2）VGLUT 的亚细胞定位；（3）VGLUT 在与神经元其他囊泡转运体的关系中的定位；以及（4）谷氨酸共传递的功能作用。
