Methylenedioxymethamphetamine-induced serotonin deficits are followed by partial recovery over a 52-week period. Part I: Synaptosomal uptake and tissue concentrations.
The effects of a high dose methylenedioxymethamphetamine (MDMA) regimen on the serotonin (5-HT) system were evaluated over a 52-wk period. MDMA was administered to rats (20 mg/kg) 8 times at 12-hr intervals. Tissue concentrations of dopamine (DA) and 5-HT, and synaptosomal uptake of 3H-5-HT and 3H-DA were measured at 2, 8, 16, 32 or 52 wk posttreatment. Synaptosomal uptake of 3H-5-HT (hippocampus) was decreased at 2 and 8 wk, but not at 16, 32 or 52 wk after drug. 5-HT tissue concentrations were measured in frontal cortex, frontal-parietal cortex, occipital-temporal cortex, nucleus accumbens/olfactory tubercle, striatum, amygdala, hippocampus, septum, hypothalamus, ventral tegmentum/substantia nigra. Two weeks after MDMA treatment, all regions showed decreased 5-HT tissue concentrations except septum. Recovery over the 52-wk interval was noted for all depleted regions, but the rate and degree of recovery was region dependent. Frontal-parietal cortex, occipital-temporal cortex and hippocampus showed the least recovery, with significant depletions at 52 wk posttreatment. Hypothalamus showed an increase in 5-HT tissue concentrations relative to age-matched controls at 52 wk. These results indicate that a high-dose MDMA regimen results in long-lasting depletions of serotonin. The rate and degree of recovery of serotonin tissue concentrations seen over the 52-wk test period is region specific.
Sabol
K E
KE
University of Chicago, Department of Pharmacological and Physiological Sciences, Illinois, USA.
Lew
R
R
Richards
J B
JB
Vosmer
G L
GL
Seiden
L S
LS
D000818:Animals; D001923:Brain Chemistry / Q000187:drug effects*; D004298:Dopamine / Q000378:metabolism; D008297:Male; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000032:analysis / Q000378:metabolism*; D018490:Serotonin Agents / Q000633:toxicity*; D013574:Synaptosomes / Q000378:metabolism*; D013997:Time Factors
D018490:Serotonin Agents; D012701:Serotonin; D018817:N-Methyl-3,4-methylenedioxyamphetamine; D004298:Dopamine