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Mori T, Iwase Y, Uzawa N, Takahashi Y, Mochizuki A, Fukase M, Shibasaki M, Suzuki T. Synergistic effects of MDMA and ethanol on behavior: Possible effects of ethanol on dopamine D 2 -receptor-related signaling. Addict Biol 2021; 26:e13000. [PMID: 33372347 DOI: 10.1111/adb.13000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 12/01/2020] [Accepted: 12/04/2020] [Indexed: 11/30/2022]
Abstract
Polydrug abuse is common among drug abusers. In particular, psychostimulants are often taken with ethanol, and the combination of 3,4-methylenedioxymethamphetamine (MDMA) and alcohol is one of the most common forms of polydrug abuse. However, the mechanism by which these drugs influence behavior remains unclear. The present study was designed to delineate the mechanisms that underlie the effects of the interaction between MDMA and ethanol on behavior in rodents. The combination of MDMA with ethanol enhanced their locomotor-increasing, rewarding, and discriminative stimulus effects without enhancing their effects on the release of dopamine from the nucleus accumbens in rodents. In addition, ethanol potently enhanced locomotor activity produced by the dopamine receptor agonist apomorphine in mice. In antagonism tests, the dopamine D1 -receptor antagonist SCH23390, but not the D2 -receptor antagonist haloperidol, completely suppressed hyperlocomotion induced by MDMA. However, hyperlocomotion induced by the co-administration of MDMA and ethanol was potently suppressed by haloperidol. These results suggest that the synergistic effects of MDMA and ethanol are mediated through dopamine transmission, especially through postsynaptical regulation of D2 -receptor-mediated functions.
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Affiliation(s)
- Tomohisa Mori
- Department of Pharmacology Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
- Department of Toxicology Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
| | - Yoshiyuki Iwase
- Department of Pharmacology Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
- Department of Toxicology Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
| | - Naoki Uzawa
- Department of Pharmacology Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
- Department of Toxicology Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
| | - Yui Takahashi
- Department of Pharmacology Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
- Department of Toxicology Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
| | - Ayano Mochizuki
- Department of Toxicology Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
| | - Mika Fukase
- Department of Toxicology Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
| | - Masahiro Shibasaki
- Department of Pharmacology Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
- Department of Toxicology Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
| | - Tsutomu Suzuki
- Department of Toxicology Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
- Institute of Drug Addiction Research Hoshi University School of Pharmacy and Pharmaceutical Sciences Tokyo Japan
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Giménez-Gómez P, Pérez-Hernández M, Gutiérrez-López MD, Vidal R, Abuin-Martínez C, O'Shea E, Colado MI. Increasing kynurenine brain levels reduces ethanol consumption in mice by inhibiting dopamine release in nucleus accumbens. Neuropharmacology 2018; 135:581-591. [PMID: 29705534 DOI: 10.1016/j.neuropharm.2018.04.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 03/22/2018] [Accepted: 04/17/2018] [Indexed: 12/11/2022]
Abstract
Recent research suggests that ethanol (EtOH) consumption behaviour can be regulated by modifying the kynurenine (KYN) pathway, although the mechanisms involved have not yet been well elucidated. To further explore the implication of the kynurenine pathway in EtOH consumption we inhibited kynurenine 3-monooxygenase (KMO) activity with Ro 61-8048 (100 mg/kg, i.p.), which shifts the KYN metabolic pathway towards kynurenic acid (KYNA) production. KMO inhibition decreases voluntary binge EtOH consumption and EtOH preference in mice subjected to "drinking in the dark" (DID) and "two-bottle choice" paradigms, respectively. This effect seems to be a consequence of increased KYN concentration, since systemic KYN administration (100 mg/kg, i.p.) similarly deters binge EtOH consumption in the DID model. Despite KYN and KYNA being well-established ligands of the aryl hydrocarbon receptor (AhR), administration of AhR antagonists (TMF 5 mg/kg and CH-223191 20 mg/kg, i.p.) and of an agonist (TCDD 50 μg/kg, intragastric) demonstrates that signalling through this receptor is not involved in EtOH consumption behaviour. Ro 61-8048 did not alter plasma acetaldehyde concentration, but prevented EtOH-induced dopamine release in the nucleus accumbens shell. These results point to a critical involvement of the reward circuitry in the reduction of EtOH consumption induced by KYN and KYNA increments. PNU-120596 (3 mg/kg, i.p.), a positive allosteric modulator of α7-nicotinic acetylcholine receptors, partially prevented the Ro 61-8048-induced decrease in EtOH consumption. Overall, our results highlight the usefulness of manipulating the KYN pathway as a pharmacological tool for modifying EtOH consumption and point to a possible modulator of alcohol drinking behaviour.
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Affiliation(s)
- Pablo Giménez-Gómez
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense, Pza. Ramón y Cajal s/n, 28040, Madrid, Spain; Instituto de Investigación Sanitaria Hospital 12 de Octubre, 28041, Madrid, Spain; Red de Trastornos Adictivos del Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Mercedes Pérez-Hernández
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense, Pza. Ramón y Cajal s/n, 28040, Madrid, Spain; Instituto de Investigación Sanitaria Hospital 12 de Octubre, 28041, Madrid, Spain; Red de Trastornos Adictivos del Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - María Dolores Gutiérrez-López
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense, Pza. Ramón y Cajal s/n, 28040, Madrid, Spain; Instituto de Investigación Sanitaria Hospital 12 de Octubre, 28041, Madrid, Spain; Red de Trastornos Adictivos del Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Rebeca Vidal
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense, Pza. Ramón y Cajal s/n, 28040, Madrid, Spain; Instituto de Investigación Sanitaria Hospital 12 de Octubre, 28041, Madrid, Spain; Red de Trastornos Adictivos del Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Cristina Abuin-Martínez
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense, Pza. Ramón y Cajal s/n, 28040, Madrid, Spain; Instituto de Investigación Sanitaria Hospital 12 de Octubre, 28041, Madrid, Spain; Red de Trastornos Adictivos del Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Esther O'Shea
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense, Pza. Ramón y Cajal s/n, 28040, Madrid, Spain; Instituto de Investigación Sanitaria Hospital 12 de Octubre, 28041, Madrid, Spain; Red de Trastornos Adictivos del Instituto de Salud Carlos III, 28029, Madrid, Spain.
| | - María Isabel Colado
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense, Pza. Ramón y Cajal s/n, 28040, Madrid, Spain; Instituto de Investigación Sanitaria Hospital 12 de Octubre, 28041, Madrid, Spain; Red de Trastornos Adictivos del Instituto de Salud Carlos III, 28029, Madrid, Spain.
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Costa G, Morelli M, Simola N. Progression and Persistence of Neurotoxicity Induced by MDMA in Dopaminergic Regions of the Mouse Brain and Association with Noradrenergic, GABAergic, and Serotonergic Damage. Neurotox Res 2017; 32:563-574. [PMID: 28597409 DOI: 10.1007/s12640-017-9761-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 05/17/2017] [Accepted: 05/24/2017] [Indexed: 02/06/2023]
Abstract
The amphetamine-related drug 3,4-methylenedioxymethamphetamine (MDMA) is known to induce neurotoxic damage in dopaminergic regions of the mouse brain. In order to characterize how the number of administrations influenced the severity of MDMA-induced dopaminergic damage and to describe the localization and persistence of this damage, we evaluated the changes in tyrosine hydroxylase (TH) and dopamine transporter (DAT) in different regions of the mouse brain. Moreover, we investigated whether dopaminergic damage was associated with noradrenergic, GABAergic, and serotonergic damage, by evaluating the changes in noradrenaline transporter (NET), glutamic acid decarboxylase-67 (GAD-67), and serotonin transporter (SERT). Mice received 14, 28, or 36 MDMA administrations (10 mg/kg twice a week) and were sacrificed at different time points (postnatal days 85, 110, 138, or 214) for immunohistochemical evaluation. Mice receiving 28 administrations showed reduced levels of DAT-positive fibers in caudate-putamen (CPu) and medial prefrontal cortex (mPFC) and reduced levels of TH-positive nigral neurons. These mice also displayed increased NET-positive hippocampal fibers, reduced GAD-67-positive neurons in CPu and hippocampus, and reduced GAD-67-positive fibers in mPFC. Similar effects of MDMA on DAT, TH, and GAD-67 were found in mice receiving 36 administrations, which also displayed reduced levels of striatal, cortical, and hippocampal TH-immunoreactive fibers. The reductions in dopaminergic markers and GAD-67 persisted at 3 months after MDMA discontinuation. Finally, MDMA never modified the levels of SERT. These results provide further insight into the localization and persistence of MDMA-induced dopaminergic damage and show that this effect may associate with GABAergic but not noradrenergic or serotonergic damage.
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Affiliation(s)
- Giulia Costa
- Department of Biomedical Sciences, Section of Neuropsychopharmacology, University of Cagliari, Via Ospedale 72, 09124, Cagliari, Italy
| | - Micaela Morelli
- Department of Biomedical Sciences, Section of Neuropsychopharmacology, University of Cagliari, Via Ospedale 72, 09124, Cagliari, Italy. .,National Research Council of Italy, Neuroscience Institute, Cagliari, Italy.
| | - Nicola Simola
- Department of Biomedical Sciences, Section of Neuropsychopharmacology, University of Cagliari, Via Ospedale 72, 09124, Cagliari, Italy
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Von Linstow CU, Severino M, Metaxas A, Waider J, Babcock AA, Lesch KP, Gramsbergen JB, Finsen B. Effect of aging and Alzheimer's disease-like pathology on brain monoamines in mice. Neurochem Int 2017; 108:238-245. [PMID: 28414094 DOI: 10.1016/j.neuint.2017.04.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 04/10/2017] [Accepted: 04/12/2017] [Indexed: 02/09/2023]
Abstract
Aging is the greatest single risk factor of the neurodegenerative disorder Alzheimer's disease (AD). The monoaminergic system, including serotonin (5-HT), dopamine (DA) and noradrenaline (NA) modulates cognition, which is affected in AD. Changes in monoamine levels have been observed in AD, but these can both be age- and/or disease-related. We examined whether brain monoamine levels change as part of physiological aging and/or AD-like disease in APPSWE/PS1ΔE9 (APP/PS1) transgenic mice. The neocortex, hippocampus, striatum, brainstem and cerebellum of 6-, 12-, 18- and 24-month-old B6C3 wild-type (WT) mice and of 18-month old APP/PS1 and WT mice were analysed for 5-HT, DA and NA contents by high pressure liquid chromatography (HPLC), along with neocortex from 14-month-old APP/PS1 and WT mice. While, we observed no aging effect in WT mice, we detected region-specific changes in the levels of all monoamines in 18-month-old transgenic compared with WT mice. This included reductions in 5-HT (-30%), DA (-47%) and NA (-32%) levels in the neocortex and increases of 5-HT in the brainstem (+18%). No changes were observed in any of the monoamines in the neocortex from 14-month-old APP/PS1 mice. In combination, these findings indicate that aging alone is not sufficient to affect brain monoamine levels, unlike the APPSWE/PS1ΔE9 genotype.
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Affiliation(s)
- C U Von Linstow
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, J.B. Winsløws Vej 25, DK-5000 Odense C, Denmark.
| | - M Severino
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, J.B. Winsløws Vej 25, DK-5000 Odense C, Denmark.
| | - A Metaxas
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, J.B. Winsløws Vej 25, DK-5000 Odense C, Denmark.
| | - J Waider
- Section of Molecular Psychiatry, Laboratory of Translational Neuroscience, Center of Mental Health, University of Würzburg, Fuechsleinstrasse 15, 97080 Würzburg, Germany.
| | - A A Babcock
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, J.B. Winsløws Vej 25, DK-5000 Odense C, Denmark
| | - K P Lesch
- Section of Molecular Psychiatry, Laboratory of Translational Neuroscience, Center of Mental Health, University of Würzburg, Fuechsleinstrasse 15, 97080 Würzburg, Germany.
| | - J B Gramsbergen
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, J.B. Winsløws Vej 25, DK-5000 Odense C, Denmark.
| | - B Finsen
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, J.B. Winsløws Vej 25, DK-5000 Odense C, Denmark.
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Abstract
Alcohol consumption with psychostimulants is very common among drug addicts. There is little known about the possible pharmacological interactions between alcohol and psychostimulants. Among most commonly co-abused psychostimulants with alcohol are methamphetamine, cocaine, 3,4-methylenedioxymethamphetaminen, and nicotine. Co-abuse of alcohol with psychostimulants can lead to several neurophysiological dysfunctions such as decrease in brain antioxidant enzymes, disruption of learning and memory processes, cerebral hypo-perfusion, neurotransmitters depletion as well as potentiation of drug seeking behaviour. Moreover, co-abuse of alcohol and psychostimulants can lead to increase in heart rate, blood pressure, myocardial oxygen consumption and cellular stress, and the risk of developing different types of cancer. Co-abuse of alcohol with psychostimulants during pregnancy can lead to fetal brain abnormalities. Further studies are needed to investigate the pharmacokinetics, pharmacodynamics, and neurochemical changes on co-abuse of alcohol and psychostimulants.
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Affiliation(s)
- Yusuf S Althobaiti
- University of Toledo, College of Pharmacy and Pharmaceutical Sciences, Department of Pharmacology and Experimental Therapeutics, Toledo, OH, USA
| | - Youssef Sari
- University of Toledo, College of Pharmacy and Pharmaceutical Sciences, Department of Pharmacology and Experimental Therapeutics, Toledo, OH, USA
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Adeniyi PA, Ishola AO, Laoye BJ, Olatunji BP, Bankole OO, Shallie PD, Ogundele OM. Neural and behavioural changes in male periadolescent mice after prolonged nicotine-MDMA treatment. Metab Brain Dis 2016; 31:93-107. [PMID: 26088184 DOI: 10.1007/s11011-015-9691-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2015] [Accepted: 05/25/2015] [Indexed: 01/07/2023]
Abstract
The interaction between MDMA and Nicotine affects multiple brain centres and neurotransmitter systems (serotonin, dopamine and glutamate) involved in motor coordination and cognition. In this study, we have elucidated the effect of prolonged (10 days) MDMA, Nicotine and a combined Nicotine-MDMA treatment on motor-cognitive neural functions. In addition, we have shown the correlation between the observed behavioural change and neural structural changes induced by these treatments in BALB/c mice. We observed that MDMA (2 mg/Kg body weight; subcutaneous) induced a decline in motor function, while Nicotine (2 mg/Kg body weight; subcutaneous) improved motor function in male periadolescent mice. In combined treatment, Nicotine reduced the motor function decline observed in MDMA treatment, thus no significant change in motor function for the combined treatment versus the control. Nicotine or MDMA treatment reduced memory function and altered hippocampal structure. Similarly, a combined Nicotine-MDMA treatment reduced memory function when compared with the control. Ultimately, the metabolic and structural changes in these neural systems were seen to vary for the various forms of treatment. It is noteworthy to mention that a combined treatment increased the rate of lipid peroxidation in brain tissue.
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Affiliation(s)
- Philip A Adeniyi
- Cell Biology and Neurotoxicity Unit, Department of Anatomy, College of Medicine and Health Sciences, Afe Babalola University, Ado-Ekiti, Ekiti State, Nigeria
- Department of Anatomy, Obafemi Awolowo College of Health Sciences, Olabisi Onabanjo University, Ago-Iwoye, Ogun State, Nigeria
| | - Azeez O Ishola
- Neural Systems Unit, Department of Anatomy, College of Medicine and Health Sciences, Afe Babalola University, Ado-Ekiti, Ekiti State, Nigeria
| | - Babafemi J Laoye
- Neurobiology Division, Department of Biological Sciences, College of Sciences, Afe Babalola University, Ado-Ekiti, Ekiti State, Nigeria
| | - Babawale P Olatunji
- Neurobiology Division, Department of Biological Sciences, College of Sciences, Afe Babalola University, Ado-Ekiti, Ekiti State, Nigeria
| | - Oluwamolakun O Bankole
- Neurobiology Division, Department of Biological Sciences, College of Sciences, Afe Babalola University, Ado-Ekiti, Ekiti State, Nigeria
| | - Philemon D Shallie
- Department of Anatomy, Obafemi Awolowo College of Health Sciences, Olabisi Onabanjo University, Ago-Iwoye, Ogun State, Nigeria
| | - Olalekan M Ogundele
- Neural Systems Unit, Department of Anatomy, College of Medicine and Health Sciences, Afe Babalola University, Ado-Ekiti, Ekiti State, Nigeria.
- Neurobiology Division, Department of Biological Sciences, College of Sciences, Afe Babalola University, Ado-Ekiti, Ekiti State, Nigeria.
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MDMA administration during adolescence exacerbates MPTP-induced cognitive impairment and neuroinflammation in the hippocampus and prefrontal cortex. Psychopharmacology (Berl) 2014; 231:4007-18. [PMID: 24687411 DOI: 10.1007/s00213-014-3536-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 03/07/2014] [Indexed: 12/13/2022]
Abstract
RATIONALE We have recently shown that chronic exposure to 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") of adolescent mice exacerbates dopamine neurotoxicity and neuroinflammatory effects elicited by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in the substantia nigra and striatum at adulthood. OBJECTIVES The present study investigated whether the amplification of MPTP effects by previous treatment with MDMA extends to the limbic and cortical regions and consequently affects cognitive performance. METHODS Mice received MDMA (10 mg/kg, twice a day/twice a week) for 9 weeks, followed by MPTP (20 mg/kg × 4 administrations), starting 2 weeks after MDMA discontinuation. Complement type 3 receptor (CD11b) and glial fibrillary acidic protein (GFAP) were evaluated by immunohistochemistry in both the hippocampus and the medial prefrontal cortex (mPFC) to measure microglia and astroglia activation. These neurochemical evaluations were paired with an assessment of cognitive performance by means of the novel object recognition (NOR) and spontaneous alternation tasks. RESULTS MPTP administration to MDMA-pretreated mice elicited a stronger activation of CD11b and GFAP in both the hippocampus and the mPFC compared with either substance administered alone. Furthermore, NOR performance was lower in MDMA-pretreated mice administered MPTP compared with mice that received either substance alone. CONCLUSIONS These results demonstrate that MDMA-MPTP negative interactions extend to the limbic and cortical regions and may result in cognitive impairment, providing further evidence that exposure to MDMA may amplify the effects of later neurotoxic insults.
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Carvajal F, Sanchez-Amate MDC, Lerma-Cabrera JM, Cubero I. Effects of a single high dose of Chlorpyrifos in long-term feeding, ethanol consumption and ethanol preference in male Wistar rats with a previous history of continued ethanol drinking. J Toxicol Sci 2014; 39:425-35. [DOI: 10.2131/jts.39.425] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Francisca Carvajal
- Department of Psychology, Universidad Autónoma de Chile
- Department of Psychology, Universidad de Almería
| | | | - José Manuel Lerma-Cabrera
- Department of Psychology, Universidad Autónoma de Chile
- Department of Psychology, Universidad de Almería
| | - Inmaculada Cubero
- Department of Psychology, Universidad Autónoma de Chile
- Department of Psychology, Universidad de Almería
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Cocaine potentiates MDMA-induced oxidative stress but not dopaminergic neurotoxicity in mice: implications for the pathogenesis of free radical-induced neurodegenerative disorders. Psychopharmacology (Berl) 2013; 230:125-35. [PMID: 23681166 DOI: 10.1007/s00213-013-3142-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 04/30/2013] [Indexed: 10/26/2022]
Abstract
RATIONALE The drugs of abuse 3,4-methylenedioxymethamphetamine (MDMA; "ecstasy") and cocaine both increase the generation of free radicals, and in the case of MDMA, this increase in oxidative stress is involved in the dopaminergic neurotoxicity produced by the drug in mice. Oxidative stress processes are also involved in the pathogenesis of several neurodegenerative diseases. OBJECTIVES We aimed to determine the consequences of the combined administration of MDMA and cocaine on oxidative stress and dopaminergic neurotoxicity. METHODS Mice received MDMA (20 mg/kg, i.p.; two doses separated by 3 h) followed by cocaine 1, 3, 6, or 24 h after the second MDMA dose. Mice were killed between 1 h and 7 days after cocaine injection. RESULTS MDMA decreased dopamine transporter density and dopamine concentration 7 days later. Cocaine did not alter this neurotoxicity. MDMA produced an increase in the concentration of 2,3-dihydroxybenzoic acid in striatal microdialysis samples and an increase in lipid peroxidation in the striatum which were potentiated by cocaine. MDMA and cocaine given together also increased nitrate and 3-nitrotyrosine levels compared with either drug given alone. On the other hand, MDMA increased superoxide dismutase activity and decreased catalase activity, changes which were prevented by cocaine administration. In addition, cocaine administration produced an increase in glutathione peroxidase (GPx) activity in both saline-treated and MDMA-treated mice. CONCLUSIONS Cocaine potentiates MDMA-induced oxidative stress but does not produce an increase in the neurotoxicity produced by MDMA, and this lack of potentiation may involve an increase in GPx activity.
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Viñals X, Maldonado R, Robledo P. Effects of repeated treatment with MDMA on working memory and behavioural flexibility in mice. Addict Biol 2013; 18:263-73. [PMID: 22260267 DOI: 10.1111/j.1369-1600.2011.00421.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Repeated administration of 3,4-methylenedioxymethamphetamine (MDMA) produces dopaminergic neurotoxicity in mice. However, it is still not clear whether this exposure induces deficits in cognitive processing related to specific subsets of executive functioning. We evaluated the effects of neurotoxic and non-neurotoxic doses of MDMA (0, 3 and 30 mg/kg, twice daily for 4 days) on working memory and attentional set-shifting in mice, and changes in extracellular levels of dopamine (DA) in the striatum. Treatment with MDMA (30 mg/kg) disrupted performance of acquired operant alternation, and this impairment was still apparent 5 days after the last drug administration. Decreased alternation was not related to anhedonia because no differences were observed between groups in the saccharin preference test under similar experimental conditions. Correct responding on delayed alternation was increased 1 day after repeated treatment with MDMA (30 mg/kg), probably because of general behavioural quiescence. Notably, the high dose regimen of MDMA impaired attentional set-shifting related to an increase in total perseveration errors. Finally, basal extracellular levels of DA in the striatum were not modified in mice repeatedly treated with MDMA with respect to controls. However, an acute challenge with MDMA (10 mg/kg) failed to increase DA outflow in mice receiving the highest MDMA dose (30 mg/kg), corroborating a decrease in the functionality of DA transporters. Seven days after this treatment, the effects of MDMA on DA outflow were recovered. These results suggest that repeated neurotoxic doses of MDMA produce lasting impairments in recall of alternation behaviour and reduce cognitive flexibility in mice.
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Affiliation(s)
- Xavier Viñals
- Laboratory of Neuropharmacology, Pompeu Fabra University (UPF), Spain
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11
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Vidal-Infer A, Aguilar MA, Miñarro J, Rodríguez-Arias M. Effect of intermittent exposure to ethanol and MDMA during adolescence on learning and memory in adult mice. Behav Brain Funct 2012; 8:32. [PMID: 22716128 PMCID: PMC3542061 DOI: 10.1186/1744-9081-8-32] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Accepted: 05/28/2012] [Indexed: 01/14/2023] Open
Abstract
Background Heavy binge drinking is increasingly frequent among adolescents, and consumption of 3,4-methylenedioxymethamphetamine (MDMA) is often combined with ethanol (EtOH). The long-lasting effects of intermittent exposure to EtOH and MDMA during adolescence on learning and memory were evaluated in adult mice using the Hebb-Williams maze. Methods Adolescent OF1 mice were exposed to EtOH (1.25 g/kg) on two consecutive days at 48-h intervals over a 14-day period (from PD 29 to 42). MDMA (10 or 20 mg/kg) was injected twice daily at 4-h intervals over two consecutive days, and this schedule was repeated six days later (PD 33, 34, 41 and 42), resulting in a total of eight injections. Animals were initiated in the Hebb-Williams maze on PND 64. The concentration of brain monoamines in the striatum and hippocampus was then measured. Results At the doses employed, both EtOH and MDMA, administered alone or together, impaired learning in the Hebb-Williams maze, as treated animals required more time to reach the goal than their saline-treated counterparts. The groups treated during adolescence with EtOH, alone or plus MDMA, also presented longer latency scores and needed more trials to reach the acquisition criterion score. MDMA induced a decrease in striatal DA concentration, an effect that was augmented by the co-administration of EtOH. All the treatment groups displayed an imbalance in the interaction DA/serotonin. Conclusions The present findings indicate that the developing brain is highly vulnerable to the damaging effects of EtOH and/or MDMA, since mice receiving these drugs in a binge pattern during adolescence exhibit impaired learning and memory in adulthood.
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Affiliation(s)
- Antonio Vidal-Infer
- Unidad de Investigación Psicobiología de las Drogodependencias, Departamento de Psicobiología, Facultad de Psicología, Universitat de Valencia, Avda, Blasco Ibáñez 21, 46010, Valencia, Spain
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Higuera-Matas A, Montoya GL, Coria SM, Miguéns M, García-Lecumberri C, Ambrosio E. Differential gene expression in the nucleus accumbens and frontal cortex of lewis and Fischer 344 rats relevant to drug addiction. Curr Neuropharmacol 2011; 9:143-50. [PMID: 21886580 PMCID: PMC3137170 DOI: 10.2174/157015911795017290] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Revised: 04/17/2010] [Accepted: 05/26/2010] [Indexed: 11/22/2022] Open
Abstract
Drug addiction results from the interplay between social and biological factors. Among these, genetic variables play a major role. The use of genetically related inbred rat strains that differ in their preference for drugs of abuse is one approach of great importance to explore genetic determinants. Lewis and Fischer 344 rats have been extensively studied and it has been shown that the Lewis strain is especially vulnerable to the addictive properties of several drugs when compared with the Fischer 344 strain. Here, we have used microarrays to analyze gene expression profiles in the frontal cortex and nucleus accumbens of Lewis and Fischer 344 rats. Our results show that only a very limited group of genes were differentially expressed in Lewis rats when compared with the Fischer 344 strain. The genes that were induced in the Lewis strain were related to oxygen transport, neurotransmitter processing and fatty acid metabolism. On the contrary genes that were repressed in Lewis rats were involved in physiological functions such as drug and proton transport, oligodendrocyte survival and lipid catabolism. These data might be useful for the identification of genes which could be potential markers of the vulnerability to the addictive properties of drugs of abuse.
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Affiliation(s)
- A Higuera-Matas
- Departamento de Psicobiología, Facultad de Psicología, UNED, Madrid, Spain
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Intermittent ethanol exposure increases long-lasting behavioral and neurochemical effects of MDMA in adolescent mice. Psychopharmacology (Berl) 2011; 218:429-42. [PMID: 21556804 DOI: 10.1007/s00213-011-2329-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Accepted: 04/24/2011] [Indexed: 10/18/2022]
Abstract
RATIONALE Heavy binge drinking is increasingly frequent among adolescents, while ethanol (EtOH) is often used in combination with 3,4-methylenedioxymethamphetamine (MDMA). OBJECTIVES The long-lasting effects of intermittent exposure to EtOH and MDMA during adolescence on motor activity, anxiety, and social behavior were evaluated in adult mice. The concentration of brain monoamines in the striatum, cortex, and hippocampus was measured following the behavioral test. METHODS Adolescent OF1 mice were exposed to ethanol (1.25 g/kg) on two consecutive days at 48-h intervals over a 14-day period (from PND 29 to 42). A total of eight injections of MDMA (10 or 20 mg/kg) were administered twice daily at 4-h intervals over two consecutive days, and this schedule was repeated 6 days later (PND 33, 34, 41, and 42). Behavioral tests and analysis of brain monoamines took place on PND 64 to 67. RESULTS Exposure to MDMA during adolescence increased the anxiogenic response in the elevated plus maze, with adult mice spending less time in the open arms of the maze and exhibiting lower concentrations of DA in the striatum. A pattern of ethanol administration modeling binge drinking during adolescence enhanced these effects and undermined the hyperthermic response induced by MDMA. Passive avoidance was affected only when EtOH was administered alone. CONCLUSIONS Juvenile administration of MDMA and alcohol was found to cause a decrease in monoamine levels in adulthood, as well as changes in social interaction behaviors, locomotor activity, increase measures of anxiety in the elevated plus maze (EPM), and decrease step-through latencies in passive avoidance test.
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14
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Gutierrez-Lopez MD, Llopis N, Feng S, Barrett DA, O'Shea E, Colado MI. Involvement of 2-arachidonoyl glycerol in the increased consumption of and preference for ethanol of mice treated with neurotoxic doses of methamphetamine. Br J Pharmacol 2010; 160:772-83. [PMID: 20590579 DOI: 10.1111/j.1476-5381.2010.00720.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Methamphetamine (METH) is a psychostimulant amphetamine that causes long-term dopaminergic neurotoxicity in mice. Hypodopaminergic states have been demonstrated to increase voluntary ethanol (EtOH) consumption and preference. In addition, the endocannabinoid system has been demonstrated to modulate EtOH drinking behaviour. Thus, we investigated EtOH consumption in METH-lesioned animals and the role of cannabinoid (CB) signalling in this EtOH drinking. EXPERIMENTAL APPROACH Mice were treated with a neurotoxic regimen of METH, and 7 days later exposed to increasing concentrations of drinking solutions of EtOH (3, 6, 10 and 20%). Seven days after neurotoxic METH, the following biochemical determinations were carried out in limbic forebrain: CB(1) receptor density and stimulated activity, 2-arachidonoyl glycerol (2-AG) and monoacylglycerol lipase (MAGL) activity, dopamine levels and dopamine transporter density. KEY RESULTS EtOH consumption and preference were increased in METH-treated mice. Seven days after METH, a time at which both dopamine levels and density of dopamine transporters in limbic forebrain were decreased, CB(1) receptor density and activity were unaltered, but 2-AG levels were increased. At this same time-point, MAGL activity was reduced. The CB(1) receptor antagonist AM251 prevented the METH-induced increase in EtOH consumption and preference, while N-arachidonoyl maleimide, an inhibitor of MAGL, increased EtOH consumption and preference in both saline- and METH-treated mice. CONCLUSIONS AND IMPLICATIONS An increase in endocannabinoid tone may be involved in the increased consumption of and preference for EtOH displayed by METH-lesioned mice as blockade of the CB(1) receptor decreased EtOH-seeking behaviours, whereas the MAGL inhibitor increased EtOH consumption.
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Affiliation(s)
- M D Gutierrez-Lopez
- Departamento de Farmacologia, Facultad de Medicina, Universidad Complutense, Madrid, Spain
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Plaza-Zabala A, Viñals X, Maldonado R, Robledo P. Effects of repeated MDMA administration on the motivation for palatable food and extinction of operant responding in mice. Psychopharmacology (Berl) 2010; 208:563-73. [PMID: 20066403 DOI: 10.1007/s00213-009-1750-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Accepted: 11/30/2009] [Indexed: 12/01/2022]
Abstract
RATIONALE Repeated administration of 3,4-methylenedioxymethamphetamine (MDMA) produces mainly dopaminergic neurotoxicity in mice. However, the consequences of this exposure on the behavioural responses related to natural reinforcing stimuli are still largely unknown. OBJECTIVES We examined whether repeated treatment with neurotoxic and non-neurotoxic doses of MDMA could exert acute and long-lasting effects on the motivation of mice to obtain a highly palatable food and on the extinction and reinstatement of food-seeking behaviour. Food-deprived mice were first trained to acquire stable responding on fixed ratio (FR) schedules of reinforcement and then treated twice daily with saline, 3 or 30 mg/kg MDMA during four consecutive days. RESULTS The high dose of MDMA impaired instrumental responding on the first and third day of treatment, whilst no residual effects were apparent on FR5 responding at any of the doses studied 24 h after treatment withdrawal. Breaking points were decreased in mice treated with both doses of MDMA. This decrease in motivation for palatable food was not due to unspecific locomotor or coordination deficits. A resistance to extinction was observed only with the highest dose of MDMA, whilst all mice showed similar reinstatement of palatable food-seeking behaviour irrespective of previous treatment. Autoradiography of [3H]-mazindol binding revealed a decrease in striatal dopamine transporter binding only in mice treated with the highest dose of MDMA. CONCLUSIONS This study demonstrates that repeated treatment with MDMA decreases the incentive motivation for a palatable food reward and that long-lasting MDMA-induced dopaminergic neurotoxicity increases the resistance to extinction of responding in the absence of reward.
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Affiliation(s)
- Ainhoa Plaza-Zabala
- Laboratori de Neurofarmacologia, Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Calle Dr Aiguader 88, 08003 Barcelona, Spain
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Izco M, Gutierrez-Lopez MD, Marchant I, O'Shea E, Colado MI. Administration of neurotoxic doses of MDMA reduces sensitivity to ethanol and increases GAT-1 immunoreactivity in mice striatum. Psychopharmacology (Berl) 2010; 207:671-9. [PMID: 19841904 DOI: 10.1007/s00213-009-1699-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2009] [Accepted: 10/05/2009] [Indexed: 11/27/2022]
Abstract
RATIONALE Mice with reduced dopamine activity following neurotoxic doses of 3,4-methylenedioxymethamphetamine (MDMA, 'ecstasy') consume more ethanol (EtOH) and show greater preference for EtOH. In keeping with human studies and other animal models where alcohol consumption and preference are also high, MDMA treatment will reduce sensitivity to certain physiological effects of EtOH. OBJECTIVE We have examined the sensitivity to the acute effects of EtOH in MDMA-lesioned mice and the effects of EtOH on striatal gamma-aminobutyric acid (GABA) accumulation and expression of GABA subtype-1 transporter (GAT-1). METHODS C57BL/6J mice were injected with neurotoxic MDMA (30 mg/kg, three times, every 3 h, i.p.). Seven days later, mice were given EtOH (3 g/kg, i.p.) to determine the loss of righting response and the development of rapid tolerance to the hypothermic effect of EtOH. The effect of EtOH on the striatal accumulation of GABA after inhibiting GABA transaminase and on GAT-1 immunoreactivity was also determined. RESULTS Mice pre-treated with a neurotoxic dose of MDMA were less sensitive to the sedative-hypnotic effect of acute EtOH and exhibited alterations in the development of rapid tolerance to the hypothermic effect of EtOH. These animals showed an increase in striatal GAT-1 immunoreactivity. EtOH reduced GABA concentration in the striatum of non-lesioned mice, an effect not observed in MDMA-lesioned mice. CONCLUSION These findings indicate that mice with a MDMA-induced dopaminergic lesion show increased expression of striatal GAT-1 that may contribute to the lower sensitivity to EtOH-induced sedative effects and the resistance to the development of rapid tolerance to hypothermia produced by EtOH.
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Affiliation(s)
- María Izco
- Departamento de Farmacologia, Facultad de Medicina, Universidad Complutense, Madrid 28040, Spain
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17
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Peraile I, Torres E, Mayado A, Izco M, Lopez-Jimenez A, Lopez-Moreno JA, Colado MI, O'Shea E. Dopamine transporter down-regulation following repeated cocaine: implications for 3,4-methylenedioxymethamphetamine-induced acute effects and long-term neurotoxicity in mice. Br J Pharmacol 2009; 159:201-11. [PMID: 20015297 DOI: 10.1111/j.1476-5381.2009.00522.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE 3,4-Methylenedioxymethamphetamine (MDMA) and cocaine are two widely abused psychostimulant drugs targeting the dopamine transporter (DAT). DAT availability regulates dopamine neurotransmission and uptake of MDMA-derived neurotoxic metabolites. We aimed to determine the effect of cocaine pre-exposure on the acute and long-term effects of MDMA in mice. EXPERIMENTAL APPROACH Mice received a course of cocaine (20 mg*kg(-1), x2 for 3 days) followed by MDMA (20 mg*kg(-1), x2, 3 h apart). Locomotor activity, extracellular dopamine levels and dopaminergic neurotoxicity were determined. Furthermore, following the course of cocaine, DAT density in striatal plasma membrane and endosome fractions was measured. KEY RESULTS Four days after the course of cocaine, challenge with MDMA attenuated the MDMA-induced striatal dopaminergic neurotoxicity. Co-administration of the protein kinase C (PKC) inhibitor NPC 15437 prevented cocaine protection. At the same time, after the course of cocaine, DAT density was reduced in the plasma membrane and increased in the endosome fraction, and this effect was prevented by NPC 15437. The course of cocaine potentiated the MDMA-induced increase in extracellular dopamine and locomotor activity, following challenge 4 days later, compared with those pretreated with saline. CONCLUSIONS AND IMPLICATIONS Repeated cocaine treatment followed by withdrawal protected against MDMA-induced dopaminergic neurotoxicity by internalizing DAT via a mechanism which may involve PKC. Furthermore, repeated cocaine followed by withdrawal induced behavioural and neurochemical sensitization to MDMA, measures which could be indicative of increased rewarding effects of MDMA.
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Affiliation(s)
- I Peraile
- Departamento de Farmacología, Facultad de Medicina, Universidad Complutense, Madrid, Spain
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Ethanol increases the distribution of MDMA to the rat brain: possible implications in the ethanol-induced potentiation of the psychostimulant effects of MDMA. Int J Neuropsychopharmacol 2009; 12:749-59. [PMID: 19046482 DOI: 10.1017/s1461145708009693] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Ecstasy (3,4-methylenedioxymethylamphetamine; MDMA) is a popular club drug often taken with ethanol (EtOH). We recently found EtOH potentiated the psychomotor effects of MDMA in rats. This potentiation could reflect pharmacodynamic or/and pharmacokinetic processes. To test the latter hypothesis, rats were injected i.p. with 6.6 or 10 mg/kg MDMA with or without 1.5 g/kg EtOH, and were killed at 5, 15 or 60 min after injection. MDMA, its primary metabolite, 3,4-methylenedioxyamphetamine (MDA), and EtOH concentrations were determined in the plasma and the hippocampus, frontal cortex and striatum at each time-point. EtOH potentiated MDMA-induced hyperactivity mainly during the first 60 min post-administration. Fifteen and 60 min after treatment with MDMA and EtOH, MDMA concentrations were greater than after MDMA alone in the blood and the three brain regions examined. EtOH, however, did not increase the fraction of MDMA converted to MDA, as shown by unaltered MDA/MDMA ratios at either MDMA dose. Interestingly, when combined with EtOH, the distribution of MDMA and MDA in the brain was not homogeneous. Concentrations of both were much higher in the striatum and cortex, than in the hippocampus. Thus, at least part of the potentiation of the MDMA-induced hyperlocomotion by EtOH might be the result of a higher concentration of MDMA and metabolites in the blood and brain. Our results present clear evidence that EtOH increases brain and blood concentrations of MDMA and leads to the possibility of both enhanced MDMA-based neurotoxicity and increased liability for abuse.
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Couppis MH, Kennedy CH, Stanwood GD. Differences in aggressive behavior and in the mesocorticolimbic DA system between A/J and BALB/cJ mice. Synapse 2009; 62:715-24. [PMID: 18651644 DOI: 10.1002/syn.20545] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The neurotransmitters DA and serotonin are known to be important modulators of aggression, but endogenous differences in these systems between aggressive and nonaggressive animals are poorly understood. To examine this issue, the mesocorticolimbic DA and serotonin systems of two mouse strains that differ in aggressive behavior, BALB/cJ and A/J, were analyzed using high performance liquid chromatography and quantitative receptor autoradiography. Significant differences in both serotonergic and dopaminergic systems were found between aggressive and nonaggressive mice. The nonaggressive A/J mice exhibited higher DA utilization in the nucleus accumbens and prefrontal cortex, higher D1 receptor expression in the rostral pole of the accumbens, and lower D2 receptor expression throughout the accumbens, as compared with aggressive BALB/cJ mice. Although correlative in nature, these data suggest that differences in mesocorticolimbic DA and serotonin systems may contribute to endogenous differences in aggression.
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Affiliation(s)
- Maria H Couppis
- Neuroscience Graduate Program, Vanderbilt University, Nashville, Tennessee 37232, USA
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Capela JP, Carmo H, Remião F, Bastos ML, Meisel A, Carvalho F. Molecular and Cellular Mechanisms of Ecstasy-Induced Neurotoxicity: An Overview. Mol Neurobiol 2009; 39:210-71. [DOI: 10.1007/s12035-009-8064-1] [Citation(s) in RCA: 210] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Accepted: 02/27/2009] [Indexed: 11/29/2022]
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Effect of chronic ethanol exposure on the hepatotoxicity of ecstasy in mice: an ex vivo study. Toxicol In Vitro 2008; 22:910-20. [PMID: 18325728 DOI: 10.1016/j.tiv.2008.01.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2007] [Revised: 12/17/2007] [Accepted: 01/14/2008] [Indexed: 11/30/2022]
Abstract
3,4-Methylenedioxymethamphetamine (MDMA) is frequently consumed at "rave" parties by polydrug users that usually take this drug in association with ethanol. In addition, many young people are repeatedly exposed to ethanol, which likely leads to tolerance phenomena. Both compounds are metabolized in the liver, with formation of hepatotoxic metabolites, which gives high relevance to the evaluation of their putative toxicological interaction. Therefore, the aim of this study was to evaluate the toxicity induced by 0.8 and 1.6 mM MDMA to freshly isolated hepatocytes obtained from ethanol-treated mice whose tap drinking water was replaced by a 5% ethanol solution for 1 week and, afterwards, by a 12% ethanol solution for 8 weeks (ethanol group) comparatively to non-treated animals (non-ethanol group). The hepatocytes were incubated under normothermic and hyperthermic conditions in order to simulate in vitro the hyperthermic response induced in vivo by MDMA, a condition that has been recognized as a life-threatening effect associated with MDMA exposure and implicated in its hepatotoxicity. Six mice treated under the same protocol as the ethanol group were used for histological analysis, and compared to non-ethanol-treated animals. The pre-treatment of mice with ethanol caused a significant decrease in the hepatocytes yield in the isolation procedure comparatively to the non-ethanol group, which can be explained by an increase in collagen deposition along the hepatic parenchyma as observed in the histological analysis. The initial cell viability of hepatocytes suspensions was similar between ethanol and non-ethanol groups. However, the ethanol group showed a higher GSH oxidation rate, which was enhanced under hyperthermia. Additionally, a concentration-dependent MDMA-induced loss of cell viability and ATP depletion was observed for both groups, at 41 degrees C. In conclusion, the repeated treatment with ethanol seems to increase the vulnerability of freshly isolated mice hepatocytes towards pro-oxidant conditions, as ascertained by the increase in collagen deposition, lower hepatocyte yield and decreased glutathione levels. However, MDMA toxicity to the isolated hepatocytes was independent of ethanol pre-treatment, while significantly dependent on incubation temperature.
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