Neuropsychopharmacology
December 14, 2011
Michael H Baumann, Mario A Ayestas, John S. Partilla et al.
The nonmedical use of 'designer' cathinone analogs, such as 4-methylmethcathinone (mephedrone) and 3,4-methylenedioxymethcathinone (methylone), is increasing worldwide, yet little information is available regarding the mechanism of action for these drugs. Here, we employed in vitro and in vivo methods to compare neurobiological effects of mephedrone and methylone with those produced by the...
Neuropsychopharmacology
December 2011
Samantha L Rushforth, Thomas Steckler, Mohammed Shoaib
Ketamine, an NMDA-receptor antagonist, produces cognitive deficits in humans in a battery of tasks involving attention and memory. Nicotine can enhance various indices of cognitive performance, including working memory span capacity measured using the odor span task (OST). This study examined the effects of a sub-chronic ketamine treatment to model cognitive deficits associated with...
Neuropsychopharmacology
September 28, 2011
Boris B. Quednow, Michael Kometer, Mark A. Geyer et al.
241 citations
The serotonin-2A receptor (5-HT(2A)R) has been implicated in the pathogenesis of schizophrenia and related inhibitory gating and behavioral inhibition deficits of schizophrenia patients. The hallucinogen psilocybin disrupts automatic forms of sensorimotor gating and response inhibition in humans, but it is unclear so far whether the 5-HT(2A)R or 5-HT(1A)R agonist properties of its bioactive...
Neuropsychopharmacology
September 2011
John D Elsworth, Bret A Morrow, Tibor Hajszan et al.
Enduring cognitive deficits exist in schizophrenic patients, long-term abusers of phencyclidine (PCP), as well as in animal PCP models of schizophrenia. It has been suggested that cognitive performance and memory processes are coupled with remodeling of pyramidal dendritic spine synapses in prefrontal cortex (PFC), and that reduced spine density and number of spine synapses in the medial PFC of...
Neuropsychopharmacology
June 2011
Toby T Winton-Brown, Paul Allen, Sagnik Bhattacharyya et al.
Although the effects of cannabis on perception are well documented, little is known about their neural basis or how these may contribute to the formation of psychotic symptoms. We used functional magnetic resonance imaging (fMRI) to assess the effects of Delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) during visual and auditory processing in healthy volunteers. In total, 14 healthy...
Neuropsychopharmacology
May 11, 2011
Janelle H. P. van Wel, Kim P. C. Kuypers, Eef L. Theunissen et al.
52 citations
3,4-Methylenedioxymethamphetamine (MDMA) or 'ecstasy' has been associated with memory deficits during abstinence and intoxication. The human neuropharmacology of MDMA-induced memory impairment is unknown. This study investigated the role of 5-HT(2A) and 5-HT(1A) receptors in MDMA-induced memory impairment. Ketanserin is a 5-HT(2A) receptor blocker and pindolol a 5-HT(1A) receptor blocker. It...
Neuropsychopharmacology
May 2011
Amy L Bauernfeind, Mary S Dietrich, Jennifer U Blackford et al.
The serotonergic neurotoxin, 3,4-methylenedioxymethamphetamine (MDMA/Ecstasy), is a highly popular recreational drug. Human recreational MDMA users have neurocognitive and neuropsychiatric impairments, and human neuroimaging data are consistent with animal reports of serotonin neurotoxicity. However, functional neuroimaging studies have not found consistent effects of MDMA on brain...
Neuropsychopharmacology
March 2011
Yen F Tai, Rosa Hoshi, Catherine M Brignell et al.
Ecstasy (±3,4-methylenedioxymethamphetamine, MDMA) is a popular recreational drug with known serotonergic neurotoxicity. Its long-term effects on dopaminergic function are less certain. Studying the long-term effects of ecstasy is often confounded by concomitant polydrug use and the short duration of abstinence. We used (18)F-dopa positron emission tomography (PET) to investigate the long-term...
Neuropsychopharmacology
December 8, 2010
Disruption of frontal θ coherence by Δ9-tetrahydrocannabinol is associated with positive psychotic symptoms.
Neuropsychopharmacology
October 2010
Colm M P O'Tuathaigh, Magdalena Hryniewiecka, Aine Behan et al.
Cannabis use confers a two-fold increase in the risk for psychosis, with adolescent use conferring even greater risk. A high-low activity catechol-O-methyltransferase (COMT) polymorphism may modulate the effects of adolescent Δ-9-tetrahydrocannabinol (THC) exposure on the risk for adult psychosis. Mice with knockout of the COMT gene were treated chronically with THC (4.0 and 8.0 mg/kg over 20...
Neuropsychopharmacology
September 22, 2010
Philip R. Corlett, Garry D Honey, John H. Krystal et al.
Modulating glutamatergic neurotransmission induces alterations in conscious experience that mimic the symptoms of early psychotic illness. We review studies that use intravenous administration of ketamine, focusing on interindividual variability in the profundity of the ketamine experience. We will consider this individual variability within a hypothetical model of brain and cognitive function...
Neuropsychopharmacology
August 2010
Celia J A Morgan, Tom P. Freeman, Gráinne Schäfer et al.
Worldwide cannabis dependence is increasing, as is the concentration of Delta(9)-tetrahydrocannabinol (THC) in street cannabis. At the same time, the concentration of the second most abundant cannabinoid in street cannabis, cannabidiol (CBD), is decreasing. These two cannabinoids have opposing effects both pharmacologically and behaviorally when administered in the laboratory. No research has...
Neuropsychopharmacology
June 1, 2010
Giacomo Salvadore, Brian R Cornwell, Fabio Sambataro et al.
Pregenual anterior cingulate cortex (pgACC) hyperactivity differentiates treatment responders from non-responders to various pharmacological antidepressant interventions, including ketamine, an N -methyl- D -aspartate receptor antagonist. Evidence of pgACC hyperactivition during non-emotional working memory tasks in patients with major depressive disorder (MDD) highlights the importance of this...
Neuropsychopharmacology
January 2010
Yoko Nawata, Takato Hiranita, Tsuneyuki Yamamoto
(+/-)-3,4-Methylenedioxymethamphetamine (MDMA, 'Ecstasy') abusers have persistent neuropsychiatric deficits including memory impairments after the cessation of abuse. On the other hand, cannabinoid CB(1) receptors have been implicated in learning/memory, and are highly expressed in the hippocampus, a region of the brain believed to have an important function in certain forms of learning and...
Neuropsychopharmacology
November 18, 2009
Opposite effects of delta-9-tetrahydrocannabinol and cannabidiol on human brain function and psychopathology.
Neuropsychopharmacology
October 2009
Lydie J Morel, Bruno Giros, Valérie Daugé
Maternal deprivation in rats specifically leads to a vulnerability to opiate dependence. However, the impact of cannabis exposure during adolescence on this opiate vulnerability has not been investigated. Chronic dronabinol (natural delta-9 tetrahydrocannabinol, THC) exposure during postnatal days 35-49 was made in maternal deprived (D) or non-deprived (animal facility rearing, AFR) rats. The...
Neuropsychopharmacology
July 1, 2009
Adam L. Halberstadt, Iris Van der Heijden, Michael A Ruderman et al.
Although it is well established that hallucinogens act as 5-HT_2A and 5-HT_2C receptor agonists, little is known about the relative contributions of 5-HT_2A and 5-HT_2C receptors to the acute behavioral effects of these drugs. The behavioral pattern monitor was used to characterize the effects of the hallucinogen 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) on locomotor and investigatory...
Neuropsychopharmacology
February 2009
Matthijs G. Bossong, Bart N M Van Berckel, Ronald Boellaard et al.
The influence of cannabis on mental health receives growing scientific and political attention. An increasing demand for treatment of cannabis dependence has refueled the discussion about the addictive potential of cannabis. A key feature of all addictive drugs is the ability to increase synaptic dopamine levels in the striatum, a mechanism involved in their rewarding and motivating effects....
Neuropsychopharmacology
October 2008
Tiziana Rubino, Daniela Vigano', Natalia Realini et al.
Few and often contradictory reports exist on the long-term neurobiological consequences of cannabinoid consumption in adolescents. The endocannabinoid system plays an important role during the different stages of brain development as cannabinoids influence the release and action of different neurotransmitters and promote neurogenesis. This study tested whether long-lasting interference by...
Neuropsychopharmacology
October 2008
Elena H Chartoff, David Potter, Diane Damez-Werno et al.
Stress and chronic exposure to drugs of abuse can trigger addictive and depressive disorders. Both stimuli increase activity of dynorphin, a neuropeptide that acts at kappa-opioid receptors (KORs). In humans, KOR agonists cause dysphoria, raising the possibility that dynorphin modulates the depressive-like effects of stress and chronic drug use. We examined if KOR activation alters sensitivity...
Neuropsychopharmacology
September 2008
Deepak Cyril D'Souza, Mohini Ranganathan, Gabriel Braley et al.
Cannabis is one of the most widely used illicit substances and there is growing interest in the association between cannabis use and psychosis. Delta-9-Tetrahydrocannabinol (Delta-9-THC) the principal active ingredient of cannabis has been shown to induce psychotomimetic and amnestic effects in healthy individuals. Whether people who frequently use cannabis are either protected from or are...
Neuropsychopharmacology
August 2008
Michael A. Benneyworth, Randy L Smith, Elaine Sanders‐bush
Recent clinical studies in schizophrenic patients show that a selective agonist of group II metabotropic glutamate (mGlu) receptors has robust efficacy in treating positive and negative symptoms. Group II mGlu receptor agonists also modulate the in vivo activity of psychotomimetic drugs, reducing the ability of psychotomimetic hallucinogens to increase glutamatergic transmission. The use of...
Neuropsychopharmacology
May 2008
Gang Lei, Yan Xia, Kenneth M Johnson
N-methyl-D-aspartate (NMDA) receptor antagonists such as phencyclidine (PCP) can induce positive and negative symptoms of schizophrenia in humans and related effects in rodents. PCP treatment of developing rats induces apoptotic neurodegeneration and behavioral deficits later in life that mimic some symptoms of schizophrenia. The precise mechanism of PCP-induced neural degeneration is unknown....
Neuropsychopharmacology
April 2008
Brian J. Piper, Joseph B. Fraiman, Cullen B Owens et al.
High or repeated doses of the recreational drug 3,4-methylenedioxymethamphetamine (MDMA, or 'Ecstasy') produce long-lasting deficits in several markers of serotonin (5-HT) system integrity and also alter behavioral function. However, it is not yet clear whether MDMA-induced serotonergic neurotoxicity is responsible for these behavioral changes or whether other mechanisms are involved. The...
Neuropsychopharmacology
January 2008
Matthew L Banks, Paul W Czoty, H Donald Gage et al.
Although serotonin (5-HT) can interact with dopamine (DA) systems to modulate the subjective and reinforcing effects of psychostimulants such as cocaine and 3,4-methyldioxymethamphetamine (MDMA, ecstasy), the long-term effects of exposure to psychostimulants on brain 5-HT systems are not well characterized. The present study assessed 5-HT transporter (SERT) availability using positron emission...