We developed a reproducible, simple, and small-scale method for determining the re-uptake and release ofmonoamines (dopamine, serotonin (5-HT)
and norepinephrine) using rat brain synaptosomes. These assays were then applied to study the effects of different kinds of non-medically used
psychoactive drugs on monoamine re-uptake and release. The phenethylamine derivatives, 4-fluoroamphetamine, 2-methylamino-3,4-methylenedioxy-
propiophenone (methylone), 1-(1,3-benzodioxol-5-yl)-2-butanamine (BDB), and N-methyl-1-(1,3-benzodioxol-5-yl)-2-butanamine (MBDB),
had strong inhibitory effects on the re-uptake of dopamine, 5-HT and norepinephrine. 4-Fluoroamphetamine, methylone and BDB also
strongly increased the release of the three monoamines, but MBDB increased 5-HT and norepinephrine release, but had little effect on dopamine
release. However, 2,5-dimethoxy-4-iodophenethylamine (2C-I), 2,5-dimethoxy-4-ethylphenethylamine (2C-E), 2,5-dimethoxy-4-chlorophenethylamine
(2C-C), 2,4,5-trimethoxyamphetamine (TMA-2) and 2,4,6-trimethoxyamphetamine (TMA-6), which are methoxylated phenethylamine
derivatives, slightly influenced the re-uptake and release of monoamines. α-Metyltryptamine (AMT), a tryptamine derivative, was one of the strongest
re-uptake inhibitors and releasers of the three monoamines. The tryptamine derivative, 5-methoxy-α-methyltryptamine (5-MeO-AMT), also
strongly inhibited re-uptake and increased the release of the three monoamines. N,N-dipropyltryptamine (DPT), 5-methoxy-N,N-diisopropyltryptamine
(5-MeO-DIPT), 5-methoxy-N,N-methylisopropyltryptamine (5-MeO-MIPT), and 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) inhibited
monoamine re-uptake, but had a few effects on monoamine release. 1-(3-Chlorophenyl)piperazine (3CPP) and 1-(methoxyphenyl)piperazine
(4MPP), which are piperazine derivatives, inhibited monoamine re-uptake and accelerated their release. The results suggest that some designer drugs
strongly act on the central nerve system to the same extent as restricted drugs.