Direct effects of 3,4-methylenedioxymethamphetamine (MDMA) on serotonin ordopamine release and uptake in the caudate putamen, nucleus accumbens, substantia nigra pars reticulate, and the dorsal raphe nucleus slices

We examined the effects of pressure ejected 3,4-methylenedioxymethamphetami ne (MDMA) from a micropipette on direct chemically stimulated release, and on electrically stimulated serotonin (5-HT) or dopamine (DA) release in the caudate putamen (CPu), nucleus accumbens (NAc), substantia nigra pars reti culata (SNr), and the dorsal raphe nucleus (DRN) brain slices of rat, using fast cyclic voltammetry (FCV). MDMA is electroactive, oxidising at +1100 m V. When the anodic input waveform was reduced from +1.4 to +1.0 volt, MDMA was not electroactive. Using this waveform, pressure ejection of MDMA did n ot release 5-HT or DA in brain slices prepared from any of the nuclei studi ed. MDMA significantly potentiated electrically stimulated 5-HT release in the SNr and DA release in CPu. In the DRN or in the NAc, MDMA was without e ffect on peak electrically stimulated 5-HT or DA release. The rates of neur otransmitter uptake, expressed as t(1/2), were in all cases significantly d ecreased after MDMA. The results indicate that MDMA, unlike (+)amphetamine, is not as a releaser of DA or 5-HT, it is a potent inhibitor of both DA an d 5-HT uptake. Synapse 36: 275-285, 2000, (C) 2000 Wiley-Liss, Inc.