Drug Testing and Analysis
June 6, 2016
Simon D. Brandt, Pierce V. Kavanagh, Folker Westphal et al.
62 citations
Lysergic N,N-diethylamide (LSD) is perhaps one of the most intriguing psychoactive substances known and numerous analogs have been explored to a varying extent in previous decades. In 2013, N6-allyl-6-norlysergic acid diethylamide (AL-LAD) and (2’S,4’S)-lysergic acid 2,4-dimethylazetidide (LSZ) have appeared on the ‘research chemicals’ / new psychoactive substances (NPS) market in both powdered...
Pharmacology, biochemistry, and behavior
April 1, 2016
Adam L. Halberstadt
33 citations
Monoamine oxidase inhibitors (MAOIs) are often ingested together with tryptamine hallucinogens, but relatively little is known about the consequences of their combined use. We have shown previously that monoamine oxidase-A (MAO-A) inhibitors alter the locomotor profile of the hallucinogen 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) in rats, and enhance its interaction with 5-HT2A receptors....
Psychopharmacology
April 1, 2016
Adam L. Halberstadt, Natalia Slepak, James Hyun et al.
Methoxetamine (MXE) is a ketamine analog sold online that has been subject to widespread abuse for its dissociative and hallucinogenic effects. Previous studies have shown that MXE has high affinity for the phencyclidine (PCP) binding site located within the channel pore of the NMDA receptor (NMDAR), but little is known about its behavioral effects. Dissociative anesthetics such as ketamine and...
Current Topics in Behavioral Neurosciences
2016
Mark A. Geyer, Adam L. Halberstadt
104 citations
Because of the ethical and regulatory hurdles associated with human studies, much of what is known about the psychopharmacology of hallucinogens has been derived from animal models. However, developing reliable animal models has proven to be a challenging task due to the complexity and variability of hallucinogen effects in humans. This chapter focuses on three animal models that are frequently...
Drug Testing and Analysis
October 12, 2015
Simon D. Brandt, Pierce V. Kavanagh, Folker Westphal et al.
79 citations
1‐Propionyl‐ d ‐lysergic acid diethylamide hemitartrate (1P‐LSD) has become available as a ‘research chemical’ in the form of blotters and powdered material. This non‐controlled derivative of d ‐lysergic acid diethylamide (LSD) has previously not been described in the published literature despite being closely related to 1‐acetyl‐LSD (ALD‐52), which was developed in the 1950s. This study...
ACS Chemical Neuroscience
July 15, 2015
David E Nichols, M Flori Sassano, Adam L. Halberstadt et al.
81 citations
A series of N-benzylated-5-methoxytryptamine analogues was prepared and investigated, with special emphasis on substituents in the meta position of the benzyl group. A parallel series of several N-benzylated analogues of 2,5-dimethoxy-4-iodophenethylamine (2C-I) also was included for comparison of the two major templates (i.e., tryptamine and phenethylamine). A broad affinity screen at...
Neuropharmacology
February 1, 2014
Adam L. Halberstadt, Mark A. Geyer
113 citations
N-benzyl substitution markedly enhances the affinity of phenethylamine hallucinogens at the 5-HT(2A) receptor. N-benzyl substituted derivatives of 2,5-dimethoxy-4-iodophenethylamine (2C-I), such as N-(2-methoxybenzyl)-2,5-dimethoxy-4-iodophenethylamine (25I-NBOMe) and N-(2,3-methylenedioxybenzyl)-2,5-dimethoxy-4-iodophenethylamine (25I-NBMD), have appeared recently as designer drugs, but have...
Journal of Psychoactive Drugs
2014
George Greer, Charles S. Grob, Adam L. Halberstadt
New Mexico was the first state to list post-traumatic stress disorder (PTSD) as a condition for the use of medical cannabis. There are no published studies, other than case reports, of the effects of cannabis on PTSD symptoms. The purpose of the study was to report and statistically analyze psychometric data on PTSD symptoms collected during 80 psychiatric evaluations of patients applying to...
The International Journal of Neuropsychopharmacology
August 13, 2013
Adam L. Halberstadt, Mark A. Geyer
66 citations
Abstract One of the oldest models of schizophrenia is based on the effects of serotonergic hallucinogens such as mescaline, psilocybin, and (+)-lysergic acid diethylamide (LSD), which act through the serotonin 5-HT2A receptor. These compounds produce a ‘model psychosis’ in normal individuals that resembles at least some of the positive symptoms of schizophrenia. Based on these similarities, and...
Frontiers in Pharmacology
2013
Wendy K. Adams, Adam L. Halberstadt, Maarten Van den Buuse
11 citations
Antagonism of N-methyl-D-aspartate (NMDA) receptors by phencyclidine (PCP) is thought to underlie its ability to induce a schizophrenia-like syndrome in humans, yet evidence indicates it has a broader pharmacological profile. Our previous lesion studies highlighted a role for serotonergic projections from the median, but not dorsal, raphe nucleus in mediating the hyperlocomotor effects of PCP,...
Psychopharmacology
June 1, 2012
Adam L. Halberstadt, David E Nichols, Mark A. Geyer
55 citations
Ayahuasca is a psychoactive tea prepared from a combination of plants that contain a hallucinogenic tryptamine and monoamine oxidase inhibitors (MAOIs). Behavioral pattern monitor (BPM) experiments demonstrated that the combination of 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) and a behaviorally inactive dose of an MAO(A) inhibitor such as harmaline or clorgyline induces biphasic effects on...
Neuropharmacology
2011
Maarten Van den Buuse, Emma Ruimschotel, Sally Martin et al.
37 citations
Serotonin-1A (5-HT(1A)) receptors may play a role in schizophrenia and the effects of certain antipsychotic drugs. However, the mechanism of interaction of 5-HT(1A) receptors with brain systems involved in schizophrenia, remains unclear. Here we show that 5-HT(1A) receptor knockout mice display enhanced locomotor hyperactivity to acute treatment with amphetamine, a widely used animal model of...
Psychopharmacology
December 9, 2010
Adam L. Halberstadt, Virginia Lehmann-Masten, Mark A. Geyer et al.
35 citations
RATIONALE: Metabotropic glutamate (mGlu) receptors have been suggested to play a role in neuropsychiatric disorders including schizophrenia, drug abuse, and depression. Because serotonergic hallucinogens increase glutamate release and mGlu receptors modulate the response to serotonin (5-HT)(2A) activation, the interactions between serotonin 5-HT(2A) receptors and mGlu receptors may prove to be...
Journal of Psychopharmacology
December 8, 2010
Liselore Koedood, Adam L. Halberstadt, Susan B Powell et al.
212 citations
Psilocin (4-hydroxy- N, N-dimethyltryptamine) is a hallucinogen that acts as an agonist at 5-HT 1A , 5-HT 2A , and 5-HT 2C receptors. Psilocin is the active metabolite of psilocybin, a hallucinogen that is currently being investigated clinically as a potential therapeutic agent. In the present investigation, we used a combination of genetic and pharmacological approaches to identify the...
Archives of General Psychiatry
September 7, 2010
Gurpreet S Chopra, Marycie Hagerty, Charles S. Grob et al.
1,220 citations
CONTEXT: Researchers conducted extensive investigations of hallucinogens in the 1950s and 1960s. By the early 1970s, however, political and cultural pressures forced the cessation of all projects. This investigation reexamines a potentially promising clinical application of hallucinogens in the treatment of anxiety reactive to advanced-stage cancer. OBJECTIVE: To explore the safety and efficacy...
Psychopharmacology
November 24, 2009
Adam L. Halberstadt, Mark A. Geyer
76 citations
RATIONALE: Compounds that activate the 5-HT(2A) receptor, such as lysergic acid diethylamide (LSD), act as hallucinogens in humans. One notable exception is the LSD congener lisuride, which does not have hallucinogenic effects in humans even though it is a potent 5-HT(2A) agonist. LSD and other hallucinogens have been shown to disrupt prepulse inhibition (PPI), an operational measure of...
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...
Psychopharmacology
November 1, 2008
Adam L. Halberstadt, Mahalah R Buell, Virginia L Masten et al.
46 citations
The hallucinogenic tea known as ayahuasca is made from a combination of psychoactive plants that contribute the active components N,N-dimethyltryptamine (DMT) and 5-methoxy-DMT (5-MeO-DMT), as well as the monoamine oxidase (MAO) inhibitors (MAOIs) harmine and harmaline for oral activity. The present study examined the effects of 5-MeO-DMT in combination with MAOIs in rats using the behavioral...