Trafficking of dopamine transporters in psychostimulant actions.

Brain dopamine (DA) plays a pivotal role in drug addiction. Since the plasma membrane DA transporter (DAT) is critical for terminating DA neurotransmission, it is important to understand how DATs are regulated and this regulation impacts drug addiction. The number of cell surface DATs is controlled by constitutive and regulated endocytic trafficking. Psychostimulants impact this trafficking. Amphetamines, DAT substrates, cause rapid up-regulation and slower down-regulation of DAT whereas cocaine, a DAT inhibitor, increases surface DATs. Recent reports have begun to elucidate the molecular mechanisms of these psychostimulant effects and link changes in DAT trafficking to psychostimulant-induced reward/reinforcement in animal models.