Psychopharmacology
January 2007
Q David Walker, Christina N Williams, Rakesh P Jotwani et al.
3,4-Methylenedioxymethamphetamine (MDMA; "Ecstasy") use has been associated with acute toxicities and persistent depletion of the neurotransmitter serotonin (5-HT). This study investigates whether sex differences in the acute and long-term effects of MDMA exist. Male and female rats received saline or 15 mg/kg MDMA, ip, bid for 4 days. Temperature was monitored on days 1 and 4. Locomotor...
Psychopharmacology
January 2007
Daniel Kueh, Lisa E Baker
Relatively few studies have compared the discriminative stimulus effects of 3,4-methylenedioxymethamphetamine (MDMA) and cocaine, and findings from different laboratories are somewhat inconsistent. One possible reason for discrepant results may be the use of different reinforcement schedules during discrimination training. The present study compared fixed ratio (FR) 20 and variable interval...
Psychopharmacology
January 2007
Manuel E. Tancer, Chris‐ellyn Johanson
The purpose of this study was to investigate the role of serotonin (5-HT) in the effects of oral 3,4-methylenedioxymethamphetamine (MDMA) in humans. The subjective and physiological effects of 1.5 mg/kg MDMA were evaluated after 20 mg fluoxetine in eight recreational MDMA users in a double-blind, placebo-controlled study. During phase 1, participants were maintained on placebo for at least 5...
Psychopharmacology
December 1, 2006
Kirsten Krebs-Thomson, Erbert M Ruiz, Virginia L Masten et al.
96 citations
The hallucinogen 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) is structurally similar to other indoleamine hallucinogens such as LSD. The present study examined the effects of 5-MeO-DMT in rats using the Behavioral Pattern Monitor (BPM), which enables analyses of patterns of locomotor activity and exploration, and the prepulse inhibition of startle (PPI) paradigm. A series of interaction...
Psychopharmacology
October 2006
Jonathan P. Roiser, Robert D Rogers, Lynnette J Cook et al.
3, 4-Methylenedioxymethamphetamine (MDMA or "ecstasy") is a popular drug of abuse known to result in depletions of the serotonin (5-HT) system. A number of studies have reported that ecstasy users differ from controls on a variety of measures of cognitive function. However, the literature is not consistent and many negative findings were also reported. One reason for such inconsistency might be...
Psychopharmacology
July 7, 2006
Roland R. Griffiths, William A. Richards, U. Mccann et al.
1,684 citations
RationaleAlthough psilocybin has been used for centuries for religious purposes, little is known scientifically about its acute and persisting effects.ObjectivesThis double-blind study evaluated the acute and longer-term psychological effects of a high dose of psilocybin relative to a comparison compound administered under comfortable, supportive conditions.Materials and methodsThe participants...
Psychopharmacology
March 30, 2006
Jordi Riba, Sergio Romero, Eva Grasa et al.
245 citations
RationaleAyahuasca is a South American psychoactive plant tea which contains the serotonergic psychedelic N,N-dimethyltryptamine (DMT) and monoamine-oxidase inhibitors that render DMT orally active. Previous investigations with ayahuasca have highlighted a psychotropic effect profile characterized by enhanced introspective attention, with individuals reporting altered somatic perceptions and...
Psychopharmacology
March 15, 2006
Michael H. Baumann, Xiaoying Wang, Richard B Rothman
269 citations
RATIONALE: 3,4-Methylenedioxymethamphetamine (MDMA) is a widely abused illicit drug. In animals, high-dose administration of MDMA produces deficits in serotonin (5-HT) neurons (e.g., depletion of forebrain 5-HT) that have been interpreted as neurotoxicity. Whether such 5-HT deficits reflect neuronal damage is a matter of ongoing debate. OBJECTIVE: The present paper reviews four specific issues...
Psychopharmacology
January 20, 2006
Boris B. Quednow, K. Kühn, C. Hoppe et al.
RationaleIn animal studies, the common club drug 3,4-methylendioxymethamphetamine (MDMA, “Ecstasy”) consistently caused a prolonged loss of presynaptic serotonergic neurons, and evidence suggests that MDMA consumption may also affect the human serotonergic system. Serotonin (5-HT) has been implicated in the regulation of impulsivity and such executive functions as decision-making cognition. In...
Psychopharmacology
October 2005
Chad J Reissig, Justin R Eckler, R A Rabin et al.
It has been suggested that the 5-HT1A receptor plays a significant modulatory role in the stimulus effects of the indoleamine hallucinogen lysergic acid diethylamide (LSD). The present study sought to characterize the effects of several compounds with known affinity for the 5-HT1A receptor on the discriminative stimulus effects of LSD. Twelve male Fischer 344 rats were trained in a two-lever,...
Psychopharmacology
September 1, 2005
William E Fantegrossi, Andrew W Harrington, Justin R Eckler et al.
72 citations
Few studies have examined the effects of 2,5-dimethoxy-4-(n)-propylthiophenethylamine (2C-T-7) in vivo. 2C-T-7 was tested in a drug-elicited head twitch assay in mice and in several drug discrimination assays in rats; 2C-T-7 was compared to the phenylisopropylamine hallucinogen R(-)-1-(2,5-dimethoxy-4-methylphenyl)-2aminopropane (DOM) in both assays, with or without pretreatment with the...
Psychopharmacology
July 2005
Danuta Marona‐lewicka, Ronald A Thisted, David E Nichols
The effect of LSD in humans has been described as occurring in two temporal phases. The behavioral effects in rats also occur in two temporal phases: an initial suppression of exploration followed by increased locomotor activity. We decided to investigate this phenomenon from the perspective that the pharmacology might have relevance to the neurochemical mechanisms underlying psychosis....
Psychopharmacology
May 1, 2005
Yong Zhang, Eduardo R Butelman, Stefan D Schlussman et al.
198 citations
Salvinorin A is a naturally occurring hallucinogen derived from the plant Salvia divinorum. Salvinorin A is also a potent and selective kappa opioid receptor agonist in vitro. It has been shown that kappa agonists decrease dopamine levels in the caudate putamen and nucleus accumbens and cause conditioned place aversion in rodents. To study the effects of salvinorin A on basal dopamine levels in...
Psychopharmacology
May 2005
M Rizzo, C T J Lamers, C G Sauer et al.
Illicit drug use can increase driver crash risk due to loss of control over vehicle trajectory. This study asks, does recreational use of +/-3,4-Methylenedioxymethamphetamine (MDMA; ecstasy) and tetrahydrocannabinol (THC; marijuana) impair cognitive processes that help direct our safe movement through the world? This study assesses the residual effects of combined MDMA/THC use, and of THC use...
Psychopharmacology
January 11, 2005
Michael A. Benneyworth, Randy L Smith, Robert J. Barrett et al.
38 citations
RationaleThe drug discrimination procedure is the most frequently used in vivo model of hallucinogen activity. Historically, most drug discrimination studies have been conducted in the rat. With the development of genetically modified mice, a powerful new tool has become available for investigating the mechanisms of drug-induced behavior. The current paper is part of an ongoing effort to...
Psychopharmacology
December 2004
F Gerard Moeller, Joel L. Steinberg, Donald M Dougherty et al.
Methylene-dioxymethamphetamine (MDMA) is known to cause degeneration of serotonin nerve terminals after acute doses in animals. Similarly, behavioral studies in human MDMA users regularly find abnormalities in memory, mood, and impulse control. However, studies of brain function using brain imaging in MDMA users have been less consistent. The purpose of this study was to determine, using...
Psychopharmacology
September 2004
Niels Alting Von Geusau, Pieter Stalenhoef, Mariette Huizinga et al.
Long-term users of ecstasy have shown impaired performance on a multitude of cognitive abilities (most notably memory, attention, executive function). Research into the pattern of MDMA effects on executive functions remains fragmented, however. To determine more systematically what aspects of executive function are affected by a history of MDMA use, by using a model that divides executive...
Psychopharmacology
May 2004
A C Parrott
Not every tablet sold as "ecstasy" contains MDMA (3,4-methylenedioxymethamphetamine). The historical origins and evolution of this mismatch will be reviewed, in order to estimate the proportions of ecstasy tablets containing MDMA at different periods over the past 30 years. Surveys into the pharmacological constituents of ecstasy tablets, dosage levels, and empirical reports of their perceived...
Psychopharmacology
May 2004
Thomas J R Beveridge, Annis O. Mechan, Marie Sprakes et al.
3,4-Methylenedioxymethamphetamine (MDMA) administration to rats produces an acute hyperthermic response and induces localised neuronal activation, which can be visualised via expression of immediate-early genes. The pharmacological and anatomical basis of these effects are unclear. At high doses, MDMA also causes selective neurotoxicity at serotonergic nerve terminals. We investigated the...
Psychopharmacology
May 2004
M Farré, Rafael de la Torre, Brian O Mathúna et al.
3,4-Methylenedioxymethamphetamine (MDMA, "ecstasy") is increasingly used by young people for its euphoric and empathic effects. MDMA presents non-linear pharmacokinetics, probably by inhibition of cytochrome P450 isoform 2D6. Users are known to often take more than one dose per session. This practice could have serious implications for the toxicity of MDMA. To evaluate the pharmacological...
Psychopharmacology
May 2004
Karsten Heekeren, Jörg Daumann, Mark A. Geyer et al.
3,4-Methylenedioxymethamphetamine (MDMA, ecstasy) is neurotoxic upon central serotonin systems in experimental animals and probably also in humans. Serotonin is involved in the habituation, sensitization and prepulse inhibition (PPI) of the startle reflex. To study the plasticity of startle reflex in currently abstinent MDMA users. Electromyographic responses to acoustic startle stimuli (pulse...
Psychopharmacology
May 2004
Fabrizio Schifano
The issue of ecstasy-related fatalities has extensively attracted the attention of both the media and the general public, but less so of the scientific literature. The aim of the present review is to focus on the epidemiological, clinical and pharmacological issues related to ecstasy fatalities. Possibly due to a number of different reasons, the rates of ecstasy-related deaths seem to have...
Psychopharmacology
May 2004
K McCardle, S Luebbers, J D Carter et al.
It has been suggested that 3,4-methylenedioxymethamphetamine (MDMA or ecstasy) causes damage to the serotonergic system, and that this damage results in cognitive and mood impairments. To examine the effect of chronic MDMA usage on a wide battery of cognitive tests and psychological abilities and processes. In the present study, the performance of 17 participants with a history of MDMA use was...
Psychopharmacology
May 2004
Jonathan P. Roiser, Barbara J. Sahakian
3,4-Methylenedioxymethamphetamine (MDMA or "ecstasy") causes serotonin neuron damage in laboratory animals. The serotonin system is known to be important in the regulation of mood. Previous research has shown that MDMA users score higher on self-report ratings of depression than controls. However, MDMA users commonly take other illicit substances and many studies do not fully control for...
Psychopharmacology
April 1, 2004
E. Frecska, K. D. White, L. E. Luna
31 citations
RationaleDuring binocular rivalry, two incompatible images are presented to each eye and these monocular stimuli compete for perceptual dominance, with one pattern temporarily suppressed from awareness. One variant of stimulus presentation in binocular rivalry experiments is dichoptic stimulus alternation (DSA), when stimuli are applied to the eyes in rapid reversals. There is preliminary...