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Synthetic cathinones are among the most popular new psychoactive substances, being abused for their stimulant properties, which are similar to those of amphetamine and 3,4-methylenedioxymethamphetamine (MDMA). Considering that the liver is a likely target for cathinones-induced toxicity, and for their metabolic activation/detoxification, we aimed to determine the hepatotoxicity of three commonly abused synthetic cathinones: butylone, α-methylamino-butyrophenone (buphedrone) and 3,4-dimethylmethcathinone (3,4-DMMC). We characterized their cytotoxic profile in primary rat hepatocytes (PRH) and in the HepaRG and HepG2 cell lines. PRH was the most sensitive cell model, showing the lowest EC 50 values for all three substances (0.158 mM for 3,4-DMMC; 1.21 mM for butylone; 1.57 mM for buphedrone). Co-exposure of PRH to the synthetic cathinones and CYP450 inhibitors (selective and non-selective) proved that hepatic metabolism reduced the toxicity of buphedrone but increased that of butylone and 3,4-DMMC. All compounds were able to increase oxidative stress, disrupting mitochondrial homeostasis and inducing apoptotic and necrotic features, while also increasing the occurrence of acidic vesicular organelles in PRH, compatible with autophagic activation. In conclusion, butylone, buphedrone and 3,4-DMMC have hepatotoxic potential, and their toxicity lies in the interference with a number of homeostatic processes, while being influenced by their metabolic fate.

Entactogens such as 3,4-Methylenedioxymethamphetamine (MDMA, "molly", "ecstasy") appear to have unusual, potentially therapeutic, emotional effects. Understanding their mechanisms can benefit from clinical experiments with related drugs. Yet the first known drug with such properties, 3,4-Methylenedioxyamphetamine (MDA), remains poorly studied and its pharmacokinetics in humans are unknown. We conducted a within-subjects, double-blind, placebo-controlled study of 1.4 mg/kg oral racemic MDA and compared results to those from our prior similar studies with 1.5 mg/kg oral racemic MDMA. MDA was well-tolerated by participants. MDA induced robust increases in heart rate and blood pressure and increased cortisol and prolactin to a similar degree as MDMA. MDA self-report effects shared features with MDMA as well as with classical psychedelics. MDA self-report effects lasted longer than those of MDMA, with MDA effects remaining elevated at 8 h while MDMA effects resolved by 6 h. Cmax and AUC 0-∞ for MDA were 229 ± 39 (mean ± SD) and 3636 ± 958 µg/L for MDA and 92 ± 61 and 1544 ± 741 µg/L for the metabolite 4-hydroxy-3-methoxyamphetamine (HMA). There was considerable between-subject variation in MDA/HMA ratios. The similarity of MDA and MDMA pharmacokinetics suggests that the greater duration of MDA effects is due to pharmacodynamics rather than pharmacokinetics.

This article describes the context in which 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA) and other mescaline-like compounds were explored as hallucinogens for military and intelligence purposes from the 1940s to the 1960s. Germans first tested mescaline as a "truth drug" in a military context. In the 1940s, the United States military started testing hallucinogenic substances as truth drugs for interrogation and behavior manipulation. After tests carried out using mescaline and other drugs in 1950, some derivatives of mescaline were synthesized by the Army for the exploration of possible "speech-inducing" effects. After insufficient animal testing, the substances were given to patients at the New York State Psychiatric Institute (NYSPI). 3,4-Methylenedioxy-N-ethylamphetamine (MDE), a compound almost identical to MDMA, was among the compounds delivered for testing at the NYSPI. During tests with other derivatives (3,4-dimethoxyphenethylamine (DMA), 3,4-methylenedioxyphenethylamine (MDPEA), MDA) in 1952-53, an unwitting patient died in these tests, which was kept secret from the public. Research was interrupted and toxicological animal testing procedures were initiated. The secret animal studies run in 1953/1954 revealed that some of the "mescaline derivatives" tested (e.g. MDA, MDE, DMA, 3,4,5-trimethoxyamphetamine (TMA), MDMA) were considered for further testing in humans. In 1955, the military changed focus to lysergic acid diethylamide (LSD), but some interest in mescaline-like compounds remained for their ability to change mood and habit without interfering with cognition and sensory perception. Based on the known documents, it remains unclear (but probable) whether any of the mescaline derivatives tested were being used operationally., (Copyright © 2017 John Wiley & Sons, Ltd.)

Generally, pharmacokinetic studies on 3,4-methylenedioxymethamphetamine (MDMA) in blood have been performed after conjugate cleavage, without taking into account that phase II metabolites represent distinct chemical entities with their own effects and stereoselective pharmacokinetics. The aim of the present study was to stereoselectively investigate the pharmacokinetics of intact glucuronide and sulfate metabolites of MDMA in blood plasma after a controlled single MDMA dose. Plasma samples from 16 healthy participants receiving 125 mg of MDMA orally in a controlled study were analyzed using liquid chromatography-tandem mass spectroscopy after chiral derivatization. Pharmacokinetic parameters of R- and S-stereoisomers were determined. Sulfates of 3,4-dihydroxymethamphetamine (DHMA), and sulfate and glucuronide of 4-hydroxy-3-methoxymethamphetamine (HMMA) were identified, whereas free phase I metabolites were not detected. Stereoselective differences in Cmax and AUC24 were observed with the following preferences: R>S for MDMA and DHMA 4-sulfate; S>R for 3,4-methylenedioxyamphetamine (MDA), DHMA 3-sulfate, and HMMA glucuronide; and no preference in Cmax for HMMA sulfate. R/S ratios were >1 for all analytes after 24 hours, independent of the initial chiral preference. These are the first data on chiral pharmacokinetics of MDMA phase II metabolites in human plasma in vivo after controlled administration. The main human MDMA metabolites were shown to be sulfate and glucuronide conjugates., (Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.)

MDMA (3,4-methylenedioxymethamphetamine) is a substituted amphetamine and popular drug of abuse. Its mood-enhancing short-term effects may prompt its consumption under stress. Clinical studies indicate that MDMA treatment may mitigate the symptoms of stress disorders such as posttraumatic stress syndrome (PTSD). On the other hand, repeated administration of MDMA results in persistent deficits in markers of serotonergic (5-HT) nerve terminals that have been viewed as indicative of 5-HT neurotoxicity. Exposure to chronic stress has been shown to augment MDMA-induced 5-HT neurotoxicity. Here, we examine the transcriptional responses in the hippocampus to MDMA treatment of control rats and rats exposed to chronic stress. MDMA altered the expression of genes that regulate unfolded protein binding, protein folding, calmodulin-dependent protein kinase activity, and neuropeptide signaling. In stressed rats, the gene expression profile in response to MDMA was altered to affect sensory processing and responses to tissue damage in nerve sheaths. Subsequent treatment with MDMA also markedly altered the genetic responses to stress such that the stress-induced downregulation of genes related to the circadian rhythm was reversed. The data support the view that MDMA-induced transcriptional responses accompany the persistent effects of this drug on neuronal structure/function. In addition, MDMA treatment alters the stress-induced transcriptional signature.

The aim of this study was to investigate the involvement of serotonin-1A (5-HT(1A)) receptors in the effects of 3,4-methylenedioxymetamphetamine (MDMA) on prepulse inhibition of acoustic startle (PPI) by comparing male and female wild-type (WT) mice and 5-HT(1A) receptor knockout (1AKO) mice. MDMA dose-dependently decreased PPI in male and female mice although female mice were more sensitive at the 100-ms inter-stimulus interval (ISI). In male mice, 10 mg/kg MDMA disrupted PPI in 1AKO but not in WT controls. There was no genotype difference at higher or lower doses of MDMA. In female mice, there was no difference between genotypes at any dose of MDMA. Average startle was reduced by 10 mg/kg and 20 mg/kg MDMA similarly in male and female mice and all genotypes. These results show an involvement of 5-HT(1A) receptors in the effect of MDMA on PPI in male, but not female mice.

The popular synthetic drug of abuse 3,4-methylenedioxymethampetamine (MDMA) and its metabolite 3,4-methylenedioxyamphetamine (MDA) act mainly on the serotonergic system, though they also increase the amount of extracellular dopamine (DA) in the brain, presumably via reversal of the membrane dopamine transporter (DAT). As the involvement of exocytotic DA release is debated, we investigated if these drugs alter the intracellular calcium concentration ([Ca(2+)](i)) and subsequent DA exocytosis in single PC12 cells using respectively Fura-2 imaging and amperometry. MDMA and MDA did not change basal [Ca(2+)](i) or exocytosis, but inhibited depolarization-evoked increases in [Ca(2+)](i) and exocytosis following 15 min exposure to high concentrations of drugs (1 mM). Surprisingly, MDA was more potent in inhibiting exocytosis than MDMA and already inhibited exocytosis at concentrations that did not inhibit depolarization-evoked Ca(2+) influx (10-100 μM). Without 15 min pre-exposure, both drugs failed to inhibit depolarization-evoked Ca(2+) influx. These results indicate that at high concentrations both MDMA and MDA inhibit exocytosis via indirect inhibition of Ca(2+) influx, whereas at lower concentrations MDA may also reduce vesicle cycling. Our data suggest that the DAT-independent increase in extracellular DA in vivo is not due to direct stimulation of exocytosis, but rather to effects of these drugs on other neurotransmitter systems that innervate the dopaminergic system., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The amphetamine-derived designer drugs have been illegally used worldwide as recreational drugs, some of which are known to be hepatotoxic in humans. To compare their cytotoxic effects, 3,4-methylenedioxy-N-methamphetamine (MDMA) and its related analogues, N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB), 3,4-(methylenedioxyphenyl)-2-butanamine (BDB) and 2-methylamino-1-(3,4-methylenedioxyphenyl)-propane-1-one (methylone) were studied in freshly isolated rat hepatocytes. MBDB caused not only concentration (0-4.0 mM)- and time (0-2 h)-dependent cell death accompanied by the formation of cell blebs, and the loss of cellular ATP and adenine nucleotide pools, and reduced glutathione levels, but also the accumulation of oxidized glutathione. Of the other analogues examined, the cytotoxicity of MBDB and BDB was greater than that of MDMA and methylone, suggesting that hepatotoxicity is generally induced by these drugs. In addition, DNA damage and the induction of reactive oxygen species were greater after the incubation of hepatocytes with MBDB (2 and 4 mM) than after that with MDMA. In isolated liver mitochondria, MBDB/BDB resulted in a greater increase in the rate of state 4 oxygen consumption than did MDMA/methylone, indicating an uncoupling effect and a decrease in the rate of state 3 oxygen consumption in a concentration dependent manner. Furthermore, MBDB resulted in mitochondrial swelling dependent on the mitochondrial permeability transition (MPT); the effect of MDMA was less than that of MBDB. Taken collectively, these results suggest that (1) the onset of cytotoxicity caused by designer drugs such as MBDB and MDMA is linked to mitochondrial failure dependent upon the induction of the MPT accompanied by mitochondrial depolarization and depletion of ATP through uncoupling of oxidative phosphorylation in rat hepatocytes, and (2) MBDB and MDMA elicit DNA damage, suggesting that nuclei as well as mitochondria are target sites of these compounds.

Rationale: 3,4-Methylenedioxymethamphetamine (MDMA, "ecstasy") disrupts thermoregulation in rats and can lead to life-threatening hyperthermia in humans. MDMA administration can also lead to long-term neurotoxicity in animals and possibly humans., Objectives: The purpose of the current study was to extend previous results on the acute effects of MDMA on behavioral thermoregulation to a repeated dosing regime, simulating regular weekend use of ecstasy, on measures of thermoregulation and heart rate (HR)., Materials and Methods: Sprague-Dawley rats with telemetry implants were administered 40 micromol/kg MDMA on three consecutive days each week for 1 or 6 weeks before being confined to an elevated ambient temperature (TA) (HOT; 30+/-1 degrees C) or an area at room temperature (ROOM; 21.5+/-1.5 degrees C) for 30 min. After the final drug administration, rats were placed in a thermal gradient for 4 h to allow behavioral thermoregulation., Results: HOT rats showed higher core temperature (TC), HR, and locomotor activity than ROOM rats during confinement to a set TA (P<0.001). HR responses to MDMA over 6 weeks at both TAs progressively decreased with repeated dosing (P<0.05). TC was significantly higher in both 6-week groups compared to the 1-week groups (P<0.05) at the end of time in the gradient. Cortical concentrations of dihydroxyphenylacetic acid (DOPAC; P<0.05) and 5-hydroxyindole acetic acid (5-HIAA; P<0.001) decreased significantly irrespective of TA, while concentrations of dopamine and 5-HT did not change., Conclusion: Long-term treatment with MDMA resulted in apparent tolerance to the effects of the drug on HR, dysregulation of TC in thermal gradient, and depletion of cortical DOPAC and 5-HIAA.

Aim: The mechanism of MDMA (3,4-methylenedioxymethamphetamine)-induced toxicity is believed to be, in part, due to enhanced oxidative stress. As MDMA is eliminated via the kidney, the aim of this study was to investigate whether MDMA created conditions of oxidative stress within rat kidney., Methods: Adult male Wistar rats were divided into three groups, control treatment (water), acute MDMA administration (single oral dose: 5, 10, 20 or 40 mg/kg body weight) and subacute MDMA administration (5, 10, or 20 mg/kg body weight per day during 14 days). Animals were sacrificed 8 h after the single oral MDMA administration in the acute MDMA administration group and after the last MDMA administration in the subacute MDMA administration group. Rectal temperature measurements, oxidative stress status parameters and histological examinations were performed., Results: In all MDMA-administered rats, rectal temperature markedly increased peaking approximately 1 h after MDMA ingestion. Superoxide dismutase activity and thiobarbituric acid reactive substances increased after MDMA administration. Histological examinations of the kidney revealed dose-dependent disruption of tissue structure in subacute MDMA-administered rats. The latter was not observed in acute MDMA-administered rats.

A sensitive and reliable LC-ESI-MS procedure for the simultaneous determination of MDMA and its five metabolites including 4-hydroxy-3-methoxymethamphetamine (HMMA) conjugates has been established following the synthesis of two HMMA conjugates, 4-hydroxy-3-methoxymethamphetamine-glucuronide (HMMA-Glu) and 4-hydroxy-3-methoxymethamphetamine-sulfate (HMMA-Sul). Pretreatment of urine samples with methanol and LC-MS employing a C(18) semi-micro column with a gradient elution program provided the successful separations and MS determinations of these analytes within 20 min. Upon applying the method to MDMA users' urine specimens, HMMA-Glu and HMMA-Sul have been directly determined, suggesting the superiority of sulfation to glucuronidation in the HMMA phase II metabolism.

3,4-Methylenedioxymethamphetamine (MDMA or "ecstasy"), is a widely abused, psychoactive recreational drug that is known to induce neurotoxic effects. Human and rat hepatic metabolism of MDMA involves N-demethylation to 3,4-methylenedioxyamphetamine (MDA), which is also a drug of abuse. MDMA and MDA are O-demethylenated to N-methyl-alpha-methyldopamine (N-Me-alpha-MeDA) and alpha-methyldopamine (alpha-MeDA), respectively, which are both catechols that can undergo oxidation to the corresponding ortho-quinones. Ortho-quinones may be conjugated with glutathione (GSH) to form glutathionyl adducts, which can be transported into the brain and metabolized to the correspondent N-acetylcysteine (NAC) adducts. In this study we evaluated the neurotoxicity of nine MDMA metabolites, obtained by synthesis: N-Me-alpha-MeDA, alpha-MeDA and their correspondent GSH and NAC adducts. The studies were conducted in rat cortical neuronal cultures, for a 6 h of exposure period, under normal (36.5 degrees C) and hyperthermic (40 degrees C) conditions. Our findings show that thioether MDMA metabolites are strong neurotoxins, significantly more than their correspondent parent catechols. On the other hand, N-Me-alpha-MeDA and alpha-MeDA are more neurotoxic than MDMA. GSH and NAC conjugates of N-Me-alpha-MeDA and alpha-MeDA induced a concentration dependent delayed neuronal death, accompanied by activation of caspase 3, which occurred earlier in hyperthermic conditions. Furthermore, thioether MDMA metabolites time-dependently increased the production of reactive species, concentration-dependently depleted intracellular GSH and increased protein bound quinones. Finally, thioether MDMA metabolites induced neuronal death and oxidative stress was prevented by NAC, an antioxidant and GSH precursor. This study provides new insights into the neurotoxicity mechanisms of thioether MDMA metabolites and highlights their importance in "ecstasy" neurotoxicity.

In the last decade, a global trend of escalating ecstasy (MDMA, MDA, MDEA, MBDB) use was observed. Mentions on medical death certificates, last year's ecstasy use, number of drug offenders, seizures, prices and dosage levels figures were used for this descriptive and correlational study. Figures (1994-2003) were taken from the UK General Mortality Registers, from the Home Office Statistical Bulletins, from the British Crime Survey and from those reported to both the National Crime Intelligence and Forensic Science Services. A total of 394 ecstasy deaths mentions were here identified from the UK; in 42% of cases ecstasy was the sole drug mentioned. Overall, number of fatalities showed a year-per-year increase and positively correlated with: prevalence of last year's use (p < 0.01); number of offenders (p < 0.01) and number of seizures (p < 0.01) but negatively correlated with ecstasy price (p < 0.05). Price negatively correlated with: prevalence of last year's use (p < 0.001) and number of seizures (p < 0.01); but positively correlated with average MDMA dosage per tablet (p < 0.01). MDA, MDEA and MBDB accounted for a significant proportion of tablets only up to 1997, but not afterwards. Increasing production with a concomitant decrease in ecstasy price may have facilitated an increase in consumption levels and this, in turn, may have determined an increase in number of ecstasy deaths mentions. Only medical death certificates and not coroners' reports at the end of their inquests were here analysed; no data were available in respect of other drugs use and toxicology results.

3,4-Methylenedioxyamphetamine (MDA) and 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) are ring-substituted amphetamine derivatives with stimulant and hallucinogenic properties. The recreational use of these amphetamines, especially MDMA, is prevalent despite warnings of irreversible damage to the central nervous system. MDA and MDMA are primarily serotonergic neurotoxicants. Because (1) neither MDA nor MDMA produces neurotoxicity when injected directly into brain, (2) intracerebroventricular (i.c.v.) administration of some major metabolites of MDA and MDMA fails to reproduce their neurotoxicity, (3) alpha-methyldopamine (alpha-MeDA) and N-methyl-alpha-MeDA are metabolites of both MDA and MDMA, (4) alpha-MeDA and N-methyl-alpha-MeDA are readily oxidized to the corresponding ortho-quinones, which can undergo conjugation with glutathione (GSH), and (5) quinone thioethers exhibit a variety of toxicologic activities, we initiated studies on the potential role of thioether metabolites of alpha-MeDA and N-methyl-alpha-MeDA in the neurotoxicity of MDA and MDMA. Our studies have revealed that the thioether conjugates stimulate the acute release of serotonin, dopamine, and norepinephrine and produce a behavioral response commensurate with the "serotonin syndrome." Direct injection of the conjugates into rat brain also produces long-term depletions in serotonin (5-HT) concentrations, elevations in GFAP expression, and activation of microglial cells. The data are consistent with the view that thioether metabolites of alpha-MeDA and N-methyl-alpha-MeDA contribute to the neurotoxicity of the parent amphetamines.

Previously, we have shown that rats administered MDMA from postnatal (P) days 11-20 had reductions in body weight during the period of treatment and as adults they had deficits in sequential and spatial learning and memory. In the present study, to control for weight reductions, we used litters with double the number of offspring to induce growth restriction comparable to that of standard size litters treated with MDMA. Litters were treated twice daily from P11 to 20 with vehicle or MDMA (20 mg/kg) or only weighed. Males, but not females, exposed to MDMA had longer latencies and more errors in the Cincinnati water maze compared to males of the other treatments. In the Morris water maze (210 cm pool, 10x10 cm platform), the MDMA animals were impaired relative to all other treatments during acquisition. Only the MDMA females showed deficits when the platform was shifted to a new location, however, both MDMA males and females were impaired when the location of the platform was again shifted and a reduced platform (5x5 cm) used. No differences were observed in the ability to swim a straight channel, locate a platform with a cue, or the endocrine response to forced swim among the treatment groups. No differences were seen between animals injected with saline and those only weighed. The data suggest that factors, such as growth retardation, multiple injections, or the composition of the litter, do not affect the development of learning and memory impairments resulting from P11 to 20 MDMA exposure. The large litter approach offers a novel method to control for undernutrition during the preweaning period in rodents.

Reactive metabolites play an important role in 3,4-(+/-)-methylenedioxyamphetamine (MDA) and 3,4-(+/-)-methylenedioxymethamphetamine (MDMA; ecstasy)-mediated serotonergic neurotoxicity, although the specific identity of such metabolites remains unclear. 5-(Glutathion-S-yl)-alpha-methyldopamine (5-GSyl-alpha-MeDA) is a serotonergic neurotoxicant found in the bile of MDA-treated rats. The brain uptake of 5-GSyl-alpha-MeDA is decreased by glutathione (GSH), but sharply increases in animals pretreated with acivicin, an inhibitor of gamma-glutamyl transpeptidase (gamma-GT) suggesting competition between intact 5-GSyl-alpha-MeDA and GSH for the putative GSH transporter. gamma-GT is enriched in blood-brain barrier endothelial cells and is the only enzyme known to cleave the gamma-glutamyl bond of GSH. We now show that pretreatment of rats with acivicin (18 mg/kg, ip) inhibits brain microvessel endothelial gamma-GT activity by 60%, and potentiates MDA- and MDMA-mediated depletions in serotonin (5-HT) and 5-hydroxylindole acidic acid (5-HIAA) concentrations in brain regions enriched in 5-HT nerve terminal axons (striatum, cortex, hippocampus, and hypothalamus). In addition, glial fibrillary acidic protein (GFAP) expression increases in the striatum of acivicin and MDA (10 mg/kg) treated rats, but remains unchanged in animals treated with just MDA (10 mg/kg). Inhibition of endothelial cell gamma-GT at the blood-brain barrier likely enhances the uptake into brain of thioether metabolites of MDA and MDMA, such as 5-(glutathion-S-yl)-alpha-MeDA and 2,5-bis-(glutathion-S-yl)-alpha-MeDA, by increasing the pool of thioether conjugates available for uptake via the intact GSH transporter. The data indicate that thioether metabolites of MDA and MDMA contribute to the serotonergic neurotoxicity observed following peripheral administration of these drugs.

Illicit drug use by young people has changed in the last decade, with the increasing use of "designer" or "club" drugs such as ecstasy. Keeping abreast of current trends in illicit drug use prepares the primary care clinician to recognize the clinical effects of drug use, to manage drug emergencies, and to detect addictive behavior. Today's widely used drugs, their street names, their effects, and how to manage overdoses are reviewed.

Use of 3,4-methylenedioxymethamphetamine (MDMA; ecstasy) has increased dramatically in recent years, yet little is known about its effects on the developing brain. Neonatal rats were administered MDMA on days 1-10 or 11-20 (analogous to early and late human third trimester brain development). MDMA exposure had no effect on survival but did affect body weight gain during treatment. After treatment, body weight largely recovered to 90-95% of controls. MDMA exposure on days 11-20 resulted in dose-related impairments of sequential learning and spatial learning and memory, whereas neonatal rats exposed on days 1-10 showed almost no effects. At neither stage of exposure did MDMA-treated offspring show effects on swimming ability or cued learning. Brain region-specific dopamine, serotonin, and norepinephrine changes were small and were not correlated to learning changes. These findings suggest that MDMA may pose a previously unrecognized risk to the developing brain by inducing long-term deleterious effects on learning and memory.

Identification of the optical activity and simultaneous analysis of racemates (+/-) of three hallucinogens, 3,4-methylenedioxy-amphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), and 3,4-methylenedioxyethylamphetamine (MDEA), and the urinary excretion of their optical isomers in rats was performed by high-performance liquid chromatographic analysis. Analysis of optical enantiomers of three N-alkyl MDA derivatives was performed within 50 min using two different detectors, polarimetry (OR) and ultraviolet spectroscopy (UV). The OR detector proved suitable for identification of the optically active forms, whereas the UV detector was suitable for simultaneous analysis of the enantiomers in urine. After the administration of each of the three N-alkylated derivatives, rat urine specimens were collected over four intervals, 0-4, 4-12, 12-20, and 20-24 h. After the administration of 30 mg/kg of racemic MDA and MDMA, somewhat less of the S(+)-forms of unchanged MDA and MDMA than of the R(-)-forms in each urine specimen were detected, which gave R/S ratios greater than 1.00 (p < 0.01). Conversely, after the administration of 30 mg/kg of racemic MDEA, more of the S(+)-form than the R(-)-form was found in the urine, thus giving R/S ratios less than 1.00 (p < 0.01). The percentage of the dose excreted up to 24 h was approximately 29.4% of the administered dose for MDA [S(+) 13.40% and R(-) 15.98%], 5.8% for MDMA [S(+) 1.96% and R(-) 3.79%], and 7.3% for MDEA [S(+) 3.89% and R(-) 3.43%]. Urinary excretion of optical isomers of N-dealkylated MDA from MDMA and MDEA origin were the opposite of those of the unchanged forms, and their R/S ratios up to 24 h were 0.48 to 0.72 (p < 0.01) and 1.31 to 1.50 (p < 0.01), respectively. The urinary excretion rates up to 24 h were approximately 4.3% for N-dealkylated MDA from MDMA origin [S(+) 2.72% and R(-) 1.63%] and 0.8% for N-dealkylated MDA from MDEA origin [S(+) 0.36% and R(-) 0.47%]. The total percent of unchanged forms and N-dealkylated MDA was approximately 10.1% for MDMA [S(+) 4.68% and R(-) 5.42%] and 8.2% for MDEA [S(+) 4.25% and R(-) 3.91%]. The total R/S ratio of MDMA was found to be 1.95 (p < 0.01), whereas that of MDEA was 0.88 (p < 0.01). The total R/S ratio of MDA was 1.20 (p < 0.01 ), which was comparable with that of MDMA. These three R/S ratios did not conform to the theoretical values for three N-alkyl derivatives used and neither did the R/S ratios of urine specimens collected at the four interval. These results suggested the stereoselective disposition of three N-alkyl MDA analogues in rat. The method would be suitable for the forensic chemistry and toxicology analysis of specimens obtained from hallucinogen abusers.

Studies are presented on the toxicological detection of the designer drug methylenedioxyethylamphetamine [MDE, rac-N-ethyl-(3,4-methylenedioxyphenyl)-propane-2-amine] in urine after a single oral dose of 140 mg of MDE by GC-MS and fluorescence polarization immunoassay (FPIA). After acid hydrolysis, extraction and acetylation MDE and its metabolites could be detected by mass chromatography with the selected ions m/z 72, 86, 114, 150, 162 and 164, followed by identification of the peaks underlying full mass spectra by computer library search. The following metabolites could be detected: unchanged MDE and 3,4-dihydroxyethylamphetamine (DHE) for 33-62 h, 3,4-methylenedioxyamphetamine (MDA) for 32-36 h and 4-hydroxy-3-methoxyethylamphetamine (HME) for 7-8 days. 3,4-Dihydroxyamphetamine (DHA), 4-hydroxy-3-methoxyamphetamine (HMA), piperonyl acetone, 3,4-dihydroxyphenyl acetone and 4-hydroxy-3-methoxyphenyl acetone could only be detected in trace amounts within the first few hours. The Abbott TD x FPIA assay amphetamine/metamphetamine II gave positive results in urine for 33-62 h. Therefore, positive immunoassay results could be confirmed by the GC-MS procedure which also allowed the differentiation of MDE and its homologues 3,4-methylenedioxymethamphetamine (MDMA) and MDA as well as other amphetamine derivatives interfering with the TD x assay. Furthermore, this GC-MS procedure allowed the simultaneous detection of most of the toxicologically relevant drugs.

Widespread use of drugs at the currently popular 'raves' has caused concern principally because of an increasing number of cases of serious toxicity and even death. The availability and use of drugs at raves, mainly in the Edinburgh area, have been investigated and self-reported use of drugs compared with results of urine screening. Use of Ecstasy and LSD have been confirmed and there is evidence to support the use of Khat. A new preparation, Herbal Ecstasy, is readily available at Edinburgh raves and appears to be widely used. All urines tested positive for one or more drugs or drug metabolites and in general analytical results correlated well with self-reported use of drugs.

The methylenedioxy analogues of amphetamine are used recreationally despite concerns raised regarding potential neurotoxicity of the parent compounds and a number of metabolites. Much has been written regarding 3,4-methylenedioxymethamphetamine (MDMA; 3,4-methylenedioxy-N-ethylamphetamine (MDE; "Eve"), despite recent reports indicating the abuse of this drug and its potentially serious side effects. An assay procedure was developed for the simultaneous quantitation of both enantiomers of MDE and its metabolite MDA; the method involves derivatization with an optically pure reagent and analysis on a gas chromatograph equipped with a capillary column and a nitrogen-phosphorus detector. Brain levels of the enantiomers of MDE and MDA were examined in the rat at different time periods after acute i.p. injections of racemic MDE and the results were compared with levels of MDMA and MDA obtained after i.p. injection of MDMA in a previous study from our laboratories. The levels of the enantiomers of MDE and MDA achieved at 1, 4, and 8 hr were lower than in the case of MDMA. Stereoselective differences in brain levels of enantiomers of the parent drug and metabolite were much less marked with MDE than with MDMA, but where these small differences did exist in the case of MDE, the (R)-(-) vs (S)-(+) relationship was opposite to that reported for MDMA.

We have used female and male transgenic (Tg) mice that carry the complete sequence of the human copper-zinc (CuZn) superoxide dismutase (SOD) gene in order to assess the lethal effects of methylenedioxyamphetamine (MDA) and methylenedioxymethamphetamine (MDMA). In contrast to non-Tg mice, both heterozygous and homozygous SOD-Tg mice showed resistance to the lethal effects of both drugs. Females of both SOD-Tg and non-Tg strains were somewhat more resistant to the effects of these drugs in comparison to males. In general, homozygous animals show greater resistance to the effects of the two drugs. These results suggest that the acute lethal effects of amphetamine-substituted analogs might involve the intracellular overproduction of the superoxide radicals secondary to hypoxic injury. The gender differences suggest that there might be hormonal-free radical scavenger interactions that offer better protection to female mice. This might be related both to the lifespan of and to the lower prevalence of Parkinson's disease in women. Future studies will need to address these issues further.

1. An investigation has been made in rats into the neurotoxic effect of the relatively selective 5-hydroxytryptamine (5-HT) neurotoxin, 3,4-methylenedioxymethamphetamine (MDMA or 'Ecstasy') using chlormethiazole and dizocilpine, both known neuroprotective compounds and also gamma-butyrolactone, ondansetron and pentobarbitone. 2. Administration of MDMA (20 mg kg-1, i.p.) resulted in a 50% loss of cortical and hippocampal 5-HT and 5-hydroxyindole acetic acid (5-HIAA) 4 days later. This reflects the long term neurotoxic loss of 5-HT that occurs. Injection of gamma-butyrolactone (GBL; 400 mg kg-1, i.p.) 5 min before and 55 min after the MDMA provided substantial protection. Pentobarbitone (25 mg kg-1, i.p.) using the same dose regime was also protective, but ondansetron (0.5 mg kg-1 or 0.1 mg kg-1, i.p.) was without effect. 3. MDMA (20 mg kg-1) had no significant effect on striatal dopamine concentration 4 days later but did produce a small decrease in 3,4-dihydroxyphenylacetic acid (DOPAC) content. There were few significant changes in rats given MDMA plus GBL, ondansetron or pentobarbitone. 4. A single injection of MDMA (20 mg kg-1, i.p.) resulted in a greater than 80% depletion of 5-HT in hippocampus and cortex 4 h later, reflecting the initial rapid release that had occurred. None of the neuroprotective compounds (chlormethiazole, 50 mg kg-1; dizocilpine, 1 mg kg-1; GBL, 400 mg kg-1; pentobarbitone, 25 mg kg-1) given 5 min before and 55 min after the MDMA injection, altered the degree of 5-HT loss. 5. Acute MDMA injection increased striatal dopamine content (28%) and decreased the DOPAC content. In general, administration of the drugs under investigation did not significantly alter these MDMA-induced changes. Both chlormethiazole and GBL produced a greater increase in dopamine than MDMA alone, but this was apparently an additive effect to the action of either drug alone. 6. The 5-HT loss 4 h following administration of the neurotoxin p-chloroamphetamine (2.5 mg kg-1,i.p.) was not affected by chlormethiazole or dizocilpine. p-Chloroamphetamine did not appear to alter striatal dopamine metabolism.7. None of the protective drugs inhibited the initial 5-HT loss following MDMA, rendering unlikely any proposal that they are protective because they inhibit 5-HT release and the subsequent formation ofa toxic indole derivative. All the protective compounds (unlike ondansetron) probably inhibit dopamine release in the striatum. Since the neurotoxic action of some substituted amphetamines is dependent on the integrity of nigro-striatal neurones, this fact may go some way to explain the protective action of this diverse group of compounds.

The cross-reactivity, stereoselectivity and clinical performance of the EMIT-d.a.u. monoclonal amphetamine/methamphetamine immunoassay (EM) for the detection of methylenedioxyamphetamine (MDA) and methylenedioxymethamphetamine (MDMA) in urine was evaluated. The cut-off concentrations of racemic MDA and MDMA were found to be approximately 800 ng/ml and 3000 ng/ml, respectively. The EM assay demonstrated a high selectivity for the S(+) isomer of both MDA and MDMA. Urines collected over a 24-h period from rats administered 20 mg i.v. racemic MDMA were all positive when analyzed by the EM assay. The EM was found vastly superior to the EMIT d.a.u. polyclonal amphetamine/methamphetamine assay for the detection of MDA and MDMA. The EM assay displayed sufficient sensitivity for detection of these drugs following clinical intoxication.

MDMA (3,4-methylenedioxymethamphetamine) has been reported to produce serotonergic depletion in nonhuman primates at doses as low as 2.5 mg/kg (1-2 times the typical human dose). The current study evaluated the dose-response relationships of MDMA (1.25-20.0 mg/kg) using regional concentrations of serotonin (5-HT) and its metabolite, 5-hydroxyindoleacetic acid (5-HIAA), and home cage behavior as endpoints. Adult female rhesus monkeys (n = 16) were treated orally with 0, 1.25, 2.5, or 20.0 mg/kg MDMA twice daily for 4 consecutive days. Eighteen behaviors were measured in the home cage prior to, during, and after MDMA treatment. One month after the last dose, the animals were sacrificed and brains dissected into several regions for neurochemical analyses. 5-HT and 5-HIAA were analyzed via HPLC/EC. The lower doses of MDMA (1.25 and 2.5 mg/kg) did not significantly alter 5-HT or 5-HIAA concentrations in any brain region except hippocampus in which 5-HT concentrations were decreased after 2.5 mg/kg. MDMA at 20.0 mg/kg significantly decreased 5-HT and 5-HIAA concentrations in several cortical and midbrain structures. However, 5-HT and 5-HIAA concentrations in brain stem and hypothalamus were not significantly altered after any dose of MDMA. Combined with previous data from this laboratory, these results indicate that the decreased concentrations of 5-HT and 5-HIAA in selected brain regions show a selective dose-response relationship for MDMA-induced neurotoxicity as measured by serotonergic depletion in the nonhuman primate.

The purpose of this study was to assess the duration of (+-)-3,4-methylenedioxymethamphetamine's (MDMA's) effects on serotonin containing neurons in nonhuman primates. Fifteen squirrel monkeys were used: three served as controls, 12 received MDMA s.c. at a dose of 5 mg/kg twice daily for 4 consecutive days. Two weeks, 10 weeks, 8 months and 18 months after drug treatment, groups (n = 3) of MDMA-treated monkeys, along with controls, were examined for regional brain content of serotonin and 5-hydroxyindoleacetic acid, and for the number of [3H] paroxetine-labeled serotonin uptake sites. Two weeks after MDMA treatment, monkeys showed profound reductions in all three serotonergic presynaptic markers. By 10 weeks, there was evidence of partial recovery in some brain regions (e.g., hippocampus, caudate nucleus, frontal cortex). However, by 18 months, it was evident that recovery did not continue, as serotonergic deficits returned to the level of severity observed 2 weeks after MDMA treatment. This was the case in all brain regions examined except the thalamus and hypothalamus. In the thalamus, the level of serotonin increased to 63% of control, whereas that of 5-hydroxyindoleacetic acid recovered completely. In the hypothalamus, concentrations of serotonin and 5-hydroxyindoleacetic acid were 140 and 187% of control, respectively. These results suggest that MDMA produces lasting effects on serotonergic neurons in nonhuman primates, with most brain regions showing evidence of persistent denervation and some showing signs of reinnervation (thalamus) or possibly even hyperinnervation (hypothalamus). The morphological and functional correlates of these enduring neurochemical changes in the MDMA-treated primate remain to be delineated.

The present investigations sought to determine the effects of 3,4-methylenedioxyamphetamine (MDA) on: 1) differential conditioning of the rabbit's nictitating membrane response to the serial compounds A-X-US (tone-light-reinforced compound) and B-X (white noise-light-unreinforced compound) by examining differential responding to A and B and their conditional control over responding to X within the compounds (Experiment 1); and 2) the ability of the compound stimuli and their components to modify the amplitude of the unconditioned nictitating membrane response (Experiment 2). Experiment 1 revealed that MDA decremented differential responding to the serial compounds and their A and B components, while enhancing conditioned responding to the X component. In addition, Experiment 2 indicated that MDA attenuated reflex modification to the compounds and their A and B components, but facilitated reflex modification to X alone. The results of these experiments indicated that MDA operated to alter the intensity, distinctiveness, and persistence (short-term memory) of stimulus representations.

There is increasing evidence linking dopamine (DA) to the long-term serotonergic (5-HT) neurotoxic effects of certain substituted amphetamines such as 3,4-methylenedioxymethamphetamine (MDMA). The present study was undertaken to examine the importance of DA metabolism, uptake inhibition and release in the long-term effects of these drugs by combining various dopaminergic agents with an analogue of MDMA that had low neurotoxic liability, namely 5,6-methylenedioxy-2-aminoindan (MDAI). Monoamine and metabolite levels and the number of 5-HT uptake sites (using [3H]paroxetine binding) were determined 3 hours or 1 week after treatments. Combining the monoamine oxidase inhibitors, clorgyline (MAOA selective) or deprenyl (MAOB selective) with MDAI did not result in any long-term reductions of serotonergic markers. Similarly, combining the DA uptake inhibitor GBR-12909 with MDAI did not result in any long-term changes in monoamine levels at 1 week. In contrast, a single pretreatment of posttreatment with the nonvesicular DA releaser S-amphetamine and MDAI resulted in small but significant long-term changes in monoamine levels. More importantly, if a subacute dosing regimen (every 12 hours for 4 days) was utilized, the combination of S-amphetamine with MDAI resulted in a marked long-term decrease in the levels of cortical, hippocampal and striatal 5-HT, 5-HIAA and the number of 5-HT uptake sites. The results are discussed in terms of the significance of DA and especially nonvesicular DA release in the long-term effects of MDMA-like drugs.

Aromatic hydroxylation has been established as a pathway for the in vivo metabolism of 3,4-(methylenedioxy)methamphetamine (MDMA) in the rat. Hydroxylation occurred at positions 2, 5 and 6 of the 3,4-methylenedioxyphenyl ring, but is favored at the 6 position. All three regioisomers of both hydroxy-MDMA and hydroxy-3,4-(methylenedioxy)amphetamine (hydroxy-MDA) were detected in the rat liver when 20 mg kg-1 of MDMA was administered. However, 6-hydroxy-MDMA and 6-hydroxy-MDA were the only hydroxylated metabolites detected in the rat brain and plasma and no hydroxylated metabolites were detected in the urine. The hydroxylated metabolites were identified by co-injection of synthetic reference compounds and comparison of the mass spectra of the trifluoroacetyl derivatives of the metabolites with the synthesized reference compounds. The regioisomers of both hydroxy-MDMA and hydroxy-MDA could not be distinguished by either single-stage or two-stage mass analysis. However, employment of a third stage of mass analysis produced distinctly different mass spectra for each of the three regioisomers.

Two persons are described who demonstrated prolonged neuropsychiatric syndromes after the ingestion of large doses of (+-)-3,4-methylenedioxymethamphetamine (MDMA), a recreationally used amphetamine analog. These cases suggest that MDMA, known to be neurotoxic to serotonin neurons in several experimental animals, may also produce untoward effects in humans. In addition, they provide evidence that ingestion of large doses of MDMA can produce lasting adverse functional consequences in vulnerable persons.

To assess the potential involvement of metabolism of 3,4-methylenedioxymethamphetamine (MDMA) to the catechol alpha-methylepinine in producing serotonergic neurotoxicity, we attempted to correlate aspects of this reaction with the neurotoxicity profile of MDMA. In contrast to the stereoselectivity of S-(+)-MDMA in causing persistent declines in rat brain 5-hydroxyindole levels, no stereochemical component to the metabolic reaction was apparent. Rat liver microsomes generated a significantly greater amount of alpha-methylepinine than did mouse microsomes, but similar amounts of metabolite were produced by brain microsomes from the two species. Formation of alpha-methylepinine by hepatic, but not brain, microsomes was inhibited by SKF 525A and induced by phenobarbital, possibly indicating a tissue specificity in cytochrome P-450-dependent metabolism of MDMA. To directly assess whether alpha-methylepine is a likely mediator of MDMA neurotoxicity, the compound was administered intracerebroventricularly. No persistent declines in biogenic amines or their metabolites were observed one week following treatment. These data suggest that alpha-methylepinine alone is not responsible for the neurotoxic effects of MDMA.

The effects of single or repeated administration of the racemic mixture of 3,4-methylenedioxymethamphetamine (MDMA; 20 mg/kg, s.c.) on the number (Bmax) of serotonin (5-HT) uptake sites as determined by [3H]paroxetine binding and the concentration of 5-HT and its major metabolite, 5-hydroxyindoleacetic acid (5-HIAA), were measured in the frontal cortex and blood platelets of rats 1 and 7 days following its administration. A single injection of MDMA significantly (P less than 0.05) decreased the number of [3H]paroxetine binding sites as well as the concentrations of 5-HT and 5-HIAA in the frontal cortex but not in platelets 7 days following administration. Repeated injections of MDMA (twice daily for 4 days) significantly (P less than 0.05) decreased the number of 5-HT uptake sites and the concentration of 5-HT and 5-HIAA in the frontal cortex but not in platelets 7 days following administration. Pretreatment with the 5-HT2/5-HT1C antagonist, ketanserin, inhibited the MDMA-induced decrease in 5-HT and 5-HIAA concentrations and the number of [3H]paroxetine binding sites in the frontal cortex 7 days following a single administration. These data are suggestive that blood platelets are less sensitive than brain tissue to the 5-HT-depleting effects of MDMA. The ability of ketanserin pretreatment to block MDMA-induced decreases in [3H]paroxetine binding sites in the frontal cortex is suggestive that 5-HT2/5-HT1C receptors may be involved in the neurotoxic effects of MDMA.

The active and inactive stereoisomers of the serotonin (5-HT2) antagonist, MDL 11,939, were used to examine the relationship between the acute effects of 3,4-methylenedioxymethamphetamine (MDMA) on the dopaminergic system and its long-term effects on the serotonergic system. Only the R-(+) stereoisomer of MDL 11,939 both reversed the acute stimulation of striatal dopamine synthesis by MDMA and prevented the deficit in forebrain 5-HT concentrations measured one week later. This acute activation of striatal dopamine synthesis by MDMA is a compensatory response to the carrier-mediated efflux of transmitter as shown by its sensitivity to the dopamine uptake inhibitor, nomifensine. It is suggested that in the absence of this enhanced synthesis, the dopaminergic neuron cannot sustain the carrier-mediated dopamine release which is a prerequisite for the development of MDMA-induced neurotoxicity. This hypothesis is supported by the observation that the administration of the dopamine precursor, L-dopa, with MDMA reverses the protective effects of 5-HT2 receptor antagonists.

(+/-)3,4-Methylenedioxymethamphetamine (MDMA) is a popular recreational drug that has been proposed to be useful as an adjunct to psychotherapy. This study assessed the neurotoxic potential of MDMA in nonhuman primates. Monkeys were repeatedly administered doses (2.50, 3.75, and 5.00 mg/kg) of MDMA subcutaneously and analyzed for regional brain content of serotonin and 5-hydroxyindoleacetic acid two weeks later. In all regions of the monkey brain examined, MDMA produced a selective dose-related depletion of serotonin and 5-hydroxyindoleacetic acid. These neurochemical deficits were associated with evidence of structural damage to serotonergic nerve fibers. In addition, MDMA produced pathological changes in nerve cell bodies in the dorsal, but not median, raphe nucleus. These results indicate that MDMA is a selective serotonergic neurotoxin in nonhuman primates and that humans using this drug may be at risk for incurring central serotonergic neuronal damage.

Using the systemically active, non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist dextrorphan, we explored the role of the NMDA receptor-calcium channel complex in the toxic mechanism of action of 3,4-methylenedioxymethamphetamine (MDMA). Rats were treated with MDMA, dextrorphan, or the combination of MDMA and increasing doses of dextrorphan, and then killed 10 days later for the assay of serotonin and dopamine in the striatum, hippocampus, and cortex. Dextrorphan totally prevented the serotonin-depleting effects of MDMA in the straitum, with a lessened but still significant blockade noted in the hippocampus and cortex. These findings may provide a clue to the molecular events underlying MDMA-induced neurotoxicity.

As dopamine (DA) causes neurochemical changes in the central serotonergic system after an acute injection of methamphetamine, the present study examined the possibility that this response is mediated through dopaminergic receptors. Pretreatment with the DA receptor antagonist, haloperidol, failed to prevent the decreases in the activity of tryptophan hydroxylase and the concentration of serotonin (5-HT) in the frontal cortex, hippocampus and neostriatum 1 hr after a single administration of methamphetamine. Because methamphetamine is also a potent releaser of 5-HT, the possibility that 5-HT receptors mediate the effects of methamphetamine was evaluated. Pretreatment with methiothepin an antagonist of both DA and 5-HT receptors, failed to prevent the decline in activity of tryptophan hydroxylase but did attenuate the decreases in concentrations of 5-HT measured in the frontal cortex and hippocampus. This attenuation is not mediated through 5-HT2 receptors, as ritanserin failed to interfere with the changes induced by methamphetamine. In addition, DA or 5-HT receptors were apparently not involved in the changes in activity of tryptophan hydroxylase and concentrations of 5-HT induced by another analogue of amphetamine, 3,4-methylenedioxymethamphetamine (MDMA). This study suggests different mechanisms are responsible for the acute and long-term changes observed in the central serotonergic system following a single or multiple doses of methamphetamine.

This study investigates a number of parameters that influence the neurotoxic effects of 3,4-methylenedioxymethamphetamine (MDMA) on serotonin (5-HT) neurons in brain. Both the dose and number of injections of MDMA affect the degree of neurotoxicity on 5-HT axons and terminals as assessed by decreases in the content of 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) and the density of 5-HT uptake sites. Repeated systemic administration of various doses of MDMA (5-20 mg/kg twice daily for 4 consecutive days) results in dose-dependent decreases in 5-HT, 5-HIAA and 5-HT uptake sites. Increasing the number of injections of MDMA resulted in progressively greater reductions in 5-HT and 5-HIAA which occurred prior to decreases in 5-HT uptake sites. In contrast, no significant changes were observed in the density of norepinephrine uptake sites following single or repeated injections of 20 mg/kg MDMA. With respect to neuronal regeneration, following an initial 90% loss of 5-HT uptake sites after treatment with MDMA, the recovery of these sites occurred over a protracted period of time; a marked 25% reduction was seen at 6 months and the concentration of 5-HT uptake sites returned to control levels at 12 months following treatment with MDMA. Pretreatment with the selective 5-HT uptake blocker, citalopram, prior to each injection of MDMA prevented the neurotoxic effects of MDMA on the 5-HT parameters described above suggesting that active uptake of MDMA or a MDMA-related substance into brain 5-HT neurons was involved in the neurotoxic actions of the drug. In addition, the neurodegenerative effects of MDMA on 5-HT neurons exhibited some species specificity as comparable decreases in cerebral cortical 5-HT, 5-HIAA and 5-HT uptake sites were observed in rat and guinea pig while no significant changes in any of these serotonergic parameters were seen in mouse brain.

Acute peripheral administration of either the (+) or (-) stereoisomer of methylenedioxymethamphetamine (MDMA) to rats results in a rapid loss of tryptophan hydroxylase (TPH) activity in several brain regions. This decline in enzyme activity precedes a decrease in serotonin (5-HT) concentrations in the same areas. An initial rise in the concentration of 5-hydroxyindole acetic acid after drug administration suggests that an increase in the turnover of 5-HT is an early event in the development of these changes. Unsuccessful attempts to reproduce the in vivo effects of MDMA on TPH activity using in vitro preparations such as cortical slices or the mouse mastocytoma cell line, P-815, suggested a requirement for an intact neuronal system or metabolism of the drug. Injection of MDMA directly into several brain regions also had no effect on TPH activity or 5-HT concentrations. However, when brain concentrations of MDMA were maintained using a constant i.c.v. infusion, TPH activity declined as observed following peripheral administration. The results, therefore, indicate that the acute effect of MDMA on 5-HT synthesis is a direct central effect of the drug which may be triggered by a sustained increase in transmitter turnover.

It has been demonstrated that repeated, subcutaneous administration of 3,4-methylenedioxymethamphetamine (MDMA) to rats, guinea pigs, and squirrel monkeys produces long-lasting depletions of serotonin (5-hydroxytryptamine; 5-HT) in several brain regions. Since evidence of degenerating 5-HT neurons has been observed in the rat brain following MDMA injections, it is likely that these depletions are due to neurotoxicity similar to that observed with other substituted amphetamines. The purpose of the present study was to determine if MDMA produces similar evidence of neurotoxicity in rhesus monkeys when administered by either the intragastric (i.g.) or subcutaneous (s.c.) route. Administration of MDMA (5.0 mg/kg/12 h x 4 days) by either i.g. or s.c. routes depleted 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) in various brain regions 2 weeks after the last injection. Further, a significant decrease in [3H]5-HT uptake sites in the hippocampus was observed in monkeys treated with MDMA by the i.g. route. Reductions in uptake sites did not achieve statistical significance when drug was administered s.c. The results suggest that repeated administration of MDMA produces long-lasting, potentially neurotoxic effects on central 5-HT neurons in primates and does so when given orally.

Although some substituted amphetamines, like MDA, produce a combination of sympathomimetic stimulation and perceptual alterations, the psychoactive qualities of MDMA are less distinctive. MDMA binds to serotonergic receptors and has been shown to potently deplete brain serotonin concentrations. Biochemical and behavioral evidence suggests that MDMA may also act on the dopamine system. The present study explored the effects of blocking serotonin receptors on MDMA and amphetamine induced locomotor hyperactivity in rats. Locomotor activity was measured in photocell cages for 120 minutes following injection of methysergide (0, 2.5, 5, 10 mg/kg) or methysergide in combination with amphetamine (0.5 mg/kg) or MDMA (10 mg/kg). Methysergide, which had no effect on its own, significantly potentiated the locomotor hyperactivity produced by MDMA but not amphetamine. Thus, the intrinsic serotonergic agonist properties of MDMA may actually counteract the indirect sympathomimetic effects thought to be responsible for the locomotor hyperactivity MDMA produces.

The behavioral effect of single administration of +/- 3,4-methylene-dioxymethamphetamine (MDMA) on rats performing on the differential-reinforcement-of-low-rate 72-second schedule (DRL 72-sec) was compared before and after a period of repeated administration of MDMA known to deplete 5-hydroxytryptamine (5-HT) levels in the brain. Single administration of MDMA decreased reinforcement rate (1, 2, 4, 6 mg/kg) and increased response rate (4,6 mg/kg) of rats performing on the DRL 72-sec schedule. This effect is typical of amphetamines and other psychomotor stimulants. Four weeks after repeated administration of MDMA (6 mg/kg twice daily for 4 days) there was an increase in sensitivity to the effect of single administration of MDMA. Doses of 2, 4 and 6 mg/kg of MDMA resulted in increases in response rate that were significantly greater after repeated MDMA administration than before. Doses of 0.5, 2, and 6 mg/kg of MDMA resulted in decreases of reinforcement rate that were significantly greater after repeated MDMA administration than before. Repeated administration of MDMA resulted in long-term depletion of serotonin levels by 30-50% in the amygdala, neostriatum, hippocampus and the frontal cortex. Norepinephrine and dopamine (DA) levels were not significantly different from control in any of the brain regions analyzed. The behavioral and neurochemical results suggest that serotonergic neurons normally exert an inhibitory action upon the psychomotor stimulant effects of MDMA. Since the psychomotor stimulant effects of amphetamines appear to be mediated primarily by the dopamine system, these results provide evidence that 5-HT and DA may represent opposing systems in the DRL schedule-controlled behavior.

Recent studies suggest that 3,4-methylenedioxymethylamphetamine (MDMA), when administered subcutaneously, is toxic to central serotonergic neurons in rats. Because humans typically self-administer this drug orally, we compared this route to the s.c. route of administration. Orally administered MDMA produced a dose-related depletion of serotonin comparable to that produced by the s.c. route. These findings suggest that MDMA, when given orally, retains it neurotoxic activity and that humans using MDMA may be at risk for developing a persistent depletion of brain serotonin.

MDMA (d,1-3,4-Methylenedioxymethamphetamine HCl; "ecstasy") self-injection (0.1-3.2 mg/kg/injection) was examined in baboons under conditions in which baseline responding was maintained by intravenous injections of cocaine HCl (0.32 mg/kg/injection). Drug was available under a FR 160-response schedule of intravenous injection. Each drug injection was followed by a 3-h time out allowing a maximum of eight injections per day. MDMA or MDMA vehicle (saline) was substituted for cocaine for a period of 14 or more days followed by a return to the cocaine baseline. MDMA (0.32-3.2 mg/kg/inj) maintained more injections and higher responses rates than were maintained by saline. The maximal number of injections maintained by MDMA and the maximal response rate maintained by MDMA were less than those maintained under baseline conditions with cocaine. The highest dose of MDMA tested maintained a cyclic pattern of self-injection, i.e., days of high numbers of injections intermixed with days of low numbers of injections. At the highest dose of MDMA tested, concurrent food maintained behavior was suppressed to an extent that food intake was also decreased.

This study compared the toxic effects of oral versus subcutaneous and single versus multiple doses of 3,4-methylenedioxymethamphetamine (MDMA) on central serotonergic neurons in non-human primates. Orally administered MDMA was approximately one-half as effective as subcutaneously administered drug. Multiple doses were more effective than single doses, but a single 5 mg/kg dose of MDMA given orally still produced a long-lasting depletion of serotonin in the monkey brain. These results indicate that when MDMA is given to monkeys in a manner similar to that employed by humans, it exerts toxic effects on central serotonergic neurons. This suggests that humans using MDMA may be at risk for incurring central serotonergic neuronal damage.