Final answer:
Reserpine irreversibly binds to VMAT, causing long-term depletion of monoamines and was used for treating high blood pressure and psychosis, whereas tetrabenazine is a reversible VMAT inhibitor, mainly used for treating movement disorders like Huntington's disease by transiently reducing dopamine release.
Step-by-step explanation:
The difference between reserpine and tetrabenazine lies in their mechanism of action and clinical applications. Reserpine is an older medication that was used to treat high blood pressure and some symptoms of psychotic disorders. It works by irreversibly binding to the vesicular monoamine transporter (VMAT) in nerve terminals, which leads to the depletion of monoamines such as dopamine, norepinephrine, and serotonin from the vesicles, and eventually their depletion from the neuron, since they are metabolized once they cannot be sequestered in vesicles.
Tetrabenazine, on the other hand, is a reversible inhibitor of VMAT, leading to a decrease in the uptake of monoamines into synaptic vesicles and a subsequent reduction in their release into the synapse. It's used primarily to treat hyperkinetic movement disorders such as Huntington's disease because of its ability to transiently diminish the amount of dopamine available for release, which helps control involuntary movements.