Use of amphetamine by recreational users of ecstasy (MDMA) is associated with reduced striatal dopamine transporter densities: a [I-123]beta-CIT SPECT study - preliminary report

Rationale: Tablets sold as ecstasy often contain not only 3,4-methylenedioxymethamphetamine (MDMA) but other compounds well known to cause dopaminergic neurotoxicity, such as (meth)amphetamine. Furthermore, the use of ecstasy in the Netherlands is often combined with the use of amphetamine. However, little is known, about the effects of ecstasy use or the combination of ecstasy and amphetamine use on dopamine (DA) neurones in the human brain. Objectives: This study was designed to investigate the effects of ecstasy as well as the combined use of ecstasy and amphetamine on the density of nigrostriatal DA neurotics. Methods: [I-123]beta-CIT SPECT was used to quantify striatal DA transporters. Striatal [I-123]beta-CIT binding ratios of control subjects (n=15) were compared with binding ratios of ecstasy users (n=29) and individuals with a history of combined ecstasy and amphetamine use (n=9) after adjustment for age. Results: Striatal [I-123]beta-CIT binding ratios were significantly lower in combined ecstasy and amphetamine users compared to sole ecstasy users (6.75 versus 8.46, respectively: -20.2%, P=0.007). Binding ratios were significantly higher in ecstasy users when compared to controls (8.46 versus 7.47, respectively: +13.2%, P=0.045). Conclusions: These initial observations suggest that the sole use of ecstasy is not related to dopaminergic neurotoxicity in humans. In contrast, the reported use of amphetamine by regular users of ecstasy seems to be associated with a reduction in nigrostriatal DA neurones.