Amphetamine increase synaptic levels of serotonin because: a. it increases the activity of the VMAT b. it blocks COMT c. it increases the activity of MAO d. it causes exchange diffusion

The correct option is d. it causes exchange diffusion

Explanation:

Amphetamines are synthetic substances with a stimulating effect. Their action lies mainly in increasing synaptic levels of monoamines by various mechanisms, including diffusion exchange through membrane transporters. Amphetamine increases extracellular concentrations of serotonin by displacing the neurotransmitter from its specific presynaptic transporter. When amphetamine binds to serotonin transporters, on the one hand it prevents it from entering the terminal and on the other it reverses the recapture mechanism so that serotonin leaves the synaptic space.