Mephedrone, compared with MDMA (ecstasy) and amphetamine, rapidly increases both dopamine and 5-HT levels in nucleus accumbens of awake rats
British Journal of Pharmacology May 26, 2011 Ján Kehr, Fumio Ichinose, Shimako Yoshitake et al.
The designer drug mephedrone, compared with MDMA (ecstasy) and amphetamine in rats, rapidly increased dopamine levels in the nucleus accumbens by 496% and serotonin levels by 941%, closely matching MDMA's serotonin release but also producing an amphetamine-like fast dopamine surge and elimination. Amphetamine raised dopamine by 412% and serotonin by only 165%. Mephedrone's dopamine levels cleared within 25 minutes, versus 303 minutes for MDMA, suggesting its brief but potent effect on the brain's reward system may underlie strong addictive potential. Locomotor activity increased most with amphetamine; mephedrone and MDMA had weaker, shorter effects.