Increasing interest in psychedelic and related drugs as potential therapies for a wide spectrum of difficult-to-treat conditions, that extend beyond neuropsychiatric disorders, provided the impetus for this themed issue. This collection of reviews and original articles includes the mechanistic basis of how these drugs act, the current status of preclinical research and progress in clinical...
Increasing interest in psychedelic and related drugs as potential therapies for a wide spectrum of difficult to treat conditions that extend beyond neuropsychiatric disorders provided the impetus for this Themed Issue. This collection of reviews and original articles includes the mechanistic basis of how these drugs act, the current status of preclinical research and progress in clinical...
Psychedelics lead to profound changes in subjective experience and behaviour, which are typically conceptualised in psychological terms rather than corresponding to an altered brain state or a distinct state of vigilance. Here, we performed chronic electrophysiological recordings from the neocortex concomitant with pupillometry in freely moving adult male mice following an injection of a...
Serotonergic psychedelic drugs are under investigation as therapies for various psychiatric disorders, including major depression. Although serotonergic psychedelic drugs are 5-HT2A receptor agonists, some such agonists are not psychedelic, potentially due to differences in 5-HT2A receptor ligand bias or signalling efficacy. Here, we investigated 5-HT2A receptor signalling properties of...
Psychedelic drugs such as LSD and psilocin were once relegated to the fringes of medical research because of their association with counterculture movements and a perceived concern about harm through recreational use, and their consequent legal prohibition in the early 1970s. However, these drugs are now experiencing a renaissance in the field of psychiatry based on increasing evidence that...
Abstract Psychedelics lead to profound changes in subjective experience and behaviour, which are typically conceptualised in psychological terms rather than corresponding to an altered brain state or a distinct state of arousal. Here, we performed chronic electrophysiological recordings from the neocortex concomitant with pupillometry in freely moving adult male mice following an injection of a...
ABSTRACT Background and Purpose Serotonergic psychedelic drugs are under renewed investigation for the potential treatment of several psychiatric disorders. While all serotonergic psychedelics have 5-HT 2A receptor activity, the explanation for why some 5-HT 2A receptor agonists are not psychedelic is unknown. To address this question, we investigated the 5-HT 2A receptor signalling bias and...
ABSTRACT Background and Purpose Serotonergic psychedelic drugs are under renewed investigation for the potential treatment of several psychiatric disorders. While all serotonergic psychedelics have 5-HT 2A receptor activity, the explanation for why some 5-HT 2A receptor agonists are not psychedelic is unknown. To address this question, we investigated the 5-HT 2A receptor signalling bias and...
SSRIs are one of the most widely used drug therapies in primary care and psychiatry, and central to the management of the most common mental health problems in today's society. Despite this, SSRIs suffer from a slow onset of therapeutic effect and relatively poor efficacy as well as adverse effects, with recent concerns being focused on a disabling SSRI discontinuation syndrome. The mechanism...
Abstract Psychedelics lead to profound changes in subjective experience and behaviour, which are typically conceptualised in psychological terms rather than corresponding to an altered brain state or a distinct state of arousal. Here, we performed chronic electrophysiological recordings from the cortex concomitant with pupillometry in freely moving adult male mice following an injection of a...
Abstract Psychedelics lead to profound changes in subjective experience and behaviour, which are typically conceptualised in psychological terms rather than corresponding to an altered brain state or a distinct state of arousal. Here, we performed chronic electrophysiological recordings from the cortex concomitant with pupillometry in freely moving adult male mice following an injection of a...
Abstract Serotonergic psychedelic drugs, such as psilocin (4-hydroxy-N,N-dimethyltryptamine), profoundly alter the quality of consciousness through mechanisms which are incompletely understood. Growing evidence suggests that a single psychedelic experience can positively impact long-term psychological well-being, with relevance for the treatment of psychiatric disorders, including depression. A...
Serotonergic psychedelic drugs, such as psilocin (4-hydroxy-N,N-dimethyltryptamine), profoundly alter the quality of consciousness through mechanisms which are incompletely understood. Growing evidence suggests that a single psychedelic experience can positively impact long-term psychological well-being, with relevance for the treatment of psychiatric disorders, including depression. A...
The development of pharmacological magnetic resonance imaging (phMRI) has presented the opportunity for investigation of the neurophysiological effects of drugs in vivo. Psilocin, a hallucinogen metabolised from psilocybin, was recently reported to evoke brain region-specific, phMRI signal changes in humans. The present study investigated the effects of psilocin in a rat model using phMRI and...
The amphetamine derivatives p-chloroamphetamine (pCA), 3,4-methylenedioxymethamphetamine (MDMA, 'Ecstasy') and D-fenfluramine can, if given repeatedly in high doses to rats, produce a degeneration of serotonergic nerve terminals which we have previously shown to result in a reduction in D-fenfluramine-evoked release of 5-HT in vivo. It is therefore possible that fenfluramine-evoked responses...
Previous work has suggested that repeated treatment with substituted amphetamines including PCA, MDMA and d-fenfluramine produces a persistent neurodegeneration which is relatively selective for the fine serotoninergic terminals arising from the dorsal raphe nucleus. The aim of the present study was to investigate whether the acute releasing effect of d-fenfluramine might also be sensitive to...
1. The possibility of 5-HT2 receptor modulation of central 5-HT1A receptor function has been examined using the 5-hydroxytryptamine (5-HT) behavioural syndrome induced by 5-HT1A receptor active drugs in rats. 2. The 5-HT2/5-HTIC antagonist ritanserin (0.1-2 mg kg-1) increased the 5-HT behavioural syndrome induced by submaximally effective doses of 8-hydroxy-2-(di-n-propylamino)tetralin...