The Role of Glutamate Transporters in Synaptic Transmission

Exocytotic release of glutamate from preformed synaptic vesicles confers great speed on synaptic signaling, but also requires mechanisms to maintain the pool of available synaptic vesicles and remove glutamate from the extracellular space. Since the axon terminal is in general located at a great distance from the cell body, synapses rely on the local recycling of both synaptic vesicle membrane and their neurotransmitter contents. In this review, we address recycling of the excitatory transmitter glutamate, focusing on transport activities that operate at the plasma membrane and the synaptic vesicle, and the role that these transporters play in determining the amplitude and time course of synaptic responses.