Vesicular monoamine transporter

Overview
The vesicular monoamine transporter is a transport protein located within the presynaptic cell.

Isoforms
It comprises the two isoforms:
 * VMAT1
 * VMAT2

Substrates
Substrates for the transporter is mainly noradrenaline, adrenaline and isoprenaline. However, other substrates include dopamine, 5-HT, guanethidine and MPP+.

Clinicial significance
It can be inhibited by reserpine and tetrabenazine.

VMAT is the main target of methamphetamine. By acting as a competitive antagonist, methamphetamine blocks the presynaptic cell's ability to use VMAT to package the above mentioned neurotransmitters into vesicles. The result is increased neurotransimtter release that is not dependent on the phasic activity of the presynaptic cell.