在中枢神经系统,谷氨酸转运体在谷氨酸一谷氨酰胺循环中发挥着重要作用。谷氨酸转运体有高亲和力转运体,即兴奋性氨基酸转运体(excitatory amino acid transporters,EAATs)和低亲和力转运体,即囊泡谷氨酸转运体(vesicular glutamate transporters,VGLUTs)两种类型。其中,VGLUTs的功能是特异地将突触囊泡外的谷氨酸转运进入突触囊泡内,它包括三个成员,分别是VGLUT1、VGLUT2和VGLUT3。一方面,VGLUT1和VGLUT2标记了所有的谷氨酸能神经元,是谷氦酸能神经元和它们轴突末端高度特异的标志;另一方面,VGLUT1标志着皮质一皮质投射,而VGLUT2则标志着丘脑一皮层投射,VGLUT3则位于抑制性突触末端。
Glutamate transporters play the key role in the glutamate cycle of glutamate-glutamine in the central nervous system. Glutamate transporters include excitatory amino acid transporters (EAATs)and vesicular glutamate transporters (VGLUTs). VGLUTs package specifically glutamate into synaptic vesicles in the presyn- aptic terminal for subsequent release into the synaptic cleft. VGLUT1, VGLUT2 and VGLUT3 are three subtypes of VGLUTs. VGLUT1 and VGLUT2 together label all glutamatergic neurons. VGLUT1 and VGLUT2 are highly specific markers of glutamatergic neurons and their axon terminals. VGLUT1 and VGLUT2 are respectively the neurochemical marker of cortico-cortical projection and thalamo-cortical projection. VGLUT3 locates on the inhibitory synapse terminals.