VAChT transporter

Synaptic vesicle neurotransmitter transporters VMAT1 VMAT2 VGAT/VIAAT VGLUT1 VGLUT2 VGLUT3 VAChT... 

The vesicular acetylcholine transport can be inhibited by vesamicol and several related compounds. Vesami-col competitively inhibits transport by binding to a cytoplasmic domain on VAChT with a Kd of 5 nM. Vesamicol binding can be used to estimate transporter number, but neither vesamicol nor its analogues are currently used clinically. 

Schafer MK, Weihe E, Varoqui H, Eiden LE, Erickson JD (1994) Distribution of the vesicular acetylcholine transporter (VAChT) in the central and peripheral nervous systems of the rat. J Mol Neurosci 5 1-26. 

Acethylcholine synthesis and release In the presynaptic cholinergic terminal. Ach, acetylcholine ChAT, choline acetyltransferase VAChT, vesicular acetylcholine transporter AChE, acetylcholineesterase CHT, choline transporter... 

Uptake of amine NTs from the neuronal cytosol into synaptic vesicles is achieved by vesicular monoamine transporters (VMAT1 and VMAT2) that sequester dopamine, epinephrine, norepinephrine and serotonin. A similar vesicle transporter (VGAT) sequesters GABA and glycine and a vesicular transporter (VAChT) sequesters acetylcholine into synaptic vesicles. 

The neurotransmitter phenotype, (i.e., what type of neurotransmitter is stored and ultimately will be released from the synaptic bouton) is determined by the identity of the neurotransmitter transporter that resides on the synaptic vesicle membrane. Although some exceptions to the rule may exist all synaptic vesicles of a given neuron normally will express only one transporter type and thus will have a dehned neurotransmitter phenotype (this concept is enveloped in what is known as Dale s principle see also Reference 19). To date, four major vesicular transporter systems have been characterized that support synaptic vesicle uptake of glutamate (VGLUT 1-3), GABA and glycine (VGAT), acetylcholine (VAChT), and monoamines such as dopamine, norepinephrine, and serotonin (VMAT 1 and 2). Vesicles that store and release neuropeptides do not have specific transporters to load and concentrate the peptides but, instead, are formed with the peptides already contained within. 

However, 44 was twofold less toxic than 48 as a result of its reduced bovine vesicular acetylcholine transporter (VAChT) binding affinity (Figure 1). 

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