3,4-Methylenedioxyamphetamine (MDA) analogues exhibit differential effects on synaptosomal release of 3H-dopamine and 3H-5-hydroxytryptamine.
The effect of various analogues of the neurotoxic amphetamine derivative, MDA (3,4-methylenedioxyamphetamine) on carrier-mediated, calcium-independent release of 3H-5-HT and 3H-DA from rat brain synaptosomes was investigated. Both enantiomers of the neurotoxic analogues MDA and MDMA (3,4-methylenedioxymethamphetamine) induce synaptosomal release of 3H-5-HT and 3H-DA in vitro. The release of 3H-5-HT induced by MDMA is partially blocked by 10(-6) M fluoxetine. The (+) enantiomers of both MDA and MDMA are more potent than the (-) enantiomers as releasers of both 3H-5-HT and 3H-DA. Eleven analogues, differing from MDA with respect to the nature and number of ring and/or side chain substituents, also show some activity in the release experiments, and are more potent as releasers of 3H-5-HT than of 3H-DA. The amphetamine derivatives (+/-)fenfluramine, (+/-)norfenfluramine, (+/-)MDE, (+/-)PCA, and d-methamphetamine are all potent releasers of 3H-5-HT and show varying degrees of activity as 3H-DA releasers. The hallucinogen DOM does not cause significant release of either 3H-monoamine. Possible long-term serotonergic neurotoxicity was assessed by quantifying the density of 5-HT uptake sites in rats treated with multiple doses of selected analogues using 3H-paroxetine to label 5-HT uptake sites. In the neurotoxicity study of the compounds investigated, only (+)MDA caused a significant loss of 5-HT uptake sites in comparison to saline-treated controls. These results are discussed in terms of the apparent structure-activity properties affecting 3H-monoamine release and their possible relevance to neurotoxicity in this series of MDA congeners.
McKenna
D J
DJ
Department of Neurology & Neurological Sciences, Stanford University Medical Center, CA 94305.
Guan
X M
XM
Shulgin
A T
AT
D015104:3,4-Methylenedioxyamphetamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000818:Animals; D004298:Dopamine / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D015394:Molecular Structure; D009420:Nervous System / Q000187:drug effects; D017374:Paroxetine; D010880:Piperidines / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism*; D012702:Serotonin Antagonists / Q000378:metabolism; D013329:Structure-Activity Relationship; D013574:Synaptosomes / Q000187:drug effects* / Q000378:metabolism; D014316:Tritium
D010880:Piperidines; D012702:Serotonin Antagonists; D014316:Tritium; D012701:Serotonin; D017374:Paroxetine; D015104:3,4-Methylenedioxyamphetamine; D004298:Dopamine