SLC6A3 and opiate dependence: Nonetheless, results from the present study provide the first evidence that AJN may exert its therapeutic action for the treatment of opioid dependence through modulation of the dopamine system, as we demonstrated that AJN not only protects the DA system from the deleterious effects of morphine (through pretreatment studies), but also counteracts against these effects (via post-treatment studies), both of which involve the maintenance of DAT, D2R and TH at normal levels.