The Vesicular acetylcholine transporter (VAChT) is a
neurotransmitter transporter which is responsible for loading
acetylcholine
Acetylcholine (ACh) is an organic chemical that functions in the brain and body of many types of animals (including humans) as a neurotransmitter. Its name is derived from its chemical structure: it is an ester of acetic acid and choline. Part ...
(ACh) into
secretory organelles in
neurons making acetylcholine available for secretion.
It is encoded by Solute carrier family 18, member 3 (SLC18A3)
gene, located within the first
intron
An intron is any nucleotide sequence within a gene that is not expressed or operative in the final RNA product. The word ''intron'' is derived from the term ''intragenic region'', i.e. a region inside a gene."The notion of the cistron .e., gene. ...
of the
choline acetyltransferase
Choline acetyltransferase (commonly abbreviated as ChAT, but sometimes CAT) is a transferase enzyme responsible for the synthesis of the neurotransmitter acetylcholine. ChAT catalyzes the transfer of an acetyl group from the coenzyme acetyl-Co ...
gene. VAChT is able to transport ACh into vesicles by relying on an exchange between
proton
A proton is a stable subatomic particle, symbol , H+, or 1H+ with a positive electric charge of +1 ''e'' elementary charge. Its mass is slightly less than that of a neutron and 1,836 times the mass of an electron (the proton–electron mass ...
s (H
+) that were previously pumped into the vesicle diffusing out, thus acting as an
antiporter
An antiporter (also called exchanger or counter-transporter) is a cotransporter and integral membrane protein involved in secondary active transport of two or more different molecules or ions across a phospholipid membrane such as the plasma memb ...
. ACh molecules are then carried into the vesicle by the action of exiting protons.
Acetylcholine transport utilizes a proton gradient established by a
vacuolar ATPase.
VAChT uptake inhibitors
Radiolabeled compounds
PET imaging of the VAChT may provide insights into early diagnosis of
Alzheimer's disease
Alzheimer's disease (AD) is a neurodegeneration, neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in short-term me ...
.
* (−)-''trans''-2-Hydroxy-3-(4-(4-
18F">Fluorine-18.html" ;"title="/nowiki>Fluorine-18">18F/nowiki>fluorobenzoyl)piperidino)tetralin; racemate: ''K''i = 2.70 nM for VAChT, 191 nM for Sigma-1 receptor">σ1, and 251 nM for σ2
References
Further reading
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External links
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Solute carrier family
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