Neurotransmitter transporters

Abstract Synaptic transmission involves two distinct types of neurotransmitter transport activity. Plasma membrane reuptake is generally considered to terminate the action of neurotransmitter in the extracellular space. Transport from the cytoplasm into secretory vesicles packages transmitter for regulated release by exocytosis. Although the two activities thus have important if not essential roles in synaptic transmission, the mechanisms of active transport, their regulation and roles in signalling remain poorly understood. Molecular analysis has also suggested previously unanticipated functions for plasma membrane and vesicular neurotransmitter transporters.