Pathophysiology of depression is related with reduced volume of the hippocampus and amygdala and hypertrophy of the nucleus accumbens. The mechanism of these changes is not well under-stood, but clinical studies have shown that administration of the fast-acting antidepressant keta-mine reversed the decrease in hippocampus and amygdala volume in depressed pat...
Introduction Psilocybin is one of the most extensively studied psychedelic drugs with a broad therapeutic potential. Despite the fact that its psychoactivity is mainly attributed to the agonism at 5-HT2A receptors, it has high binding affinity also to 5-HT2C and 5-HT1A receptors and indirectly modulates the dopaminergic system. Psilocybin and its active meta...
There is increasing interest in the therapeutic potential of psilocybin. In rodents, the serotonin precursor, 5-hydroxytryptophan (5-HTP) and psilocybin induce a characteristic 5-HT2A receptor (5-HT2AR)-mediated head twitch response (HTR), which is correlated with the human psychedelic trip. We examined the role of other serotonergic receptors and the trace ...
4-Phosphoryloxy-N,N-dimethyltryptamine (psilocybin) is a naturally occurring tertiary amine found in many mushroom species. Psilocybin is a prodrug for 4-hydroxy-N,N-dimethyltryptamine (psilocin), which induces psychedelic effects via agonist activity at the serotonin (5-HT) 2A receptor (5-HT2A). Several other 4-position ring-substituted tryptamines are pres...
Pharmacotherapy of depression is characterized by the delayed onset of action, chronic treatment requirements, and insufficient effectiveness. Ketamine, with its rapid action and long-lasting effects, represents a breakthrough in the modern pharmacotherapy of depression. The current review summarizes the latest findings on the mechanism of the antidepressant...
Introduction The 5-HT2A agonist classic psychedelic, psilocybin (O-phosphoryl-4-hydroxy-N,N-dimethyltryptamine) is a tryptophan, indole-based alkaloid present in up to 2% of certain hallucinogenic “magic” mushroom species; typically Psilocybe azurescens, semilanceata, and cyanescens,. In addition, mushrooms may contain psilocin (4-hydroxy-N,N-dimethyltryptam...
The psychedelic 5-HT2A receptor (5HT2AR) agonist psilocybin (or the active metabolite psilocin) has emerged as potential useful drug for various neuropsychiatric diseases, with a rapid onset of therapeutic activity. However, the mechanisms responsible for such effects remain incompletely characterized. We aimed to study in vitro pharmacological profile and i...
There is increasing interest in the therapeutic potential of psilocybin in psychiatric disorders. In common with other serotonergic psychedelics, psilocybin is thought to act via the 5-HT2A receptor (5-HT2AR). Serotonin is the endogenous ligand of 5-HTR. In rodents, the serotonin precursor, 5-hydroxytryptophan (5-HTP), and psilocybin, induce a characteristic...
4-phosphorloxy- N,N -dimethyltryptamine (psilocybin) is a naturally occurring psychedelic compound that is being investigated in clinical studies in conjunction with psychotherapy for treatment of several psychiatric disorders. It is well established that 4-hydroxy- N,N -dimethyltryptamine (psilocin) is the bioactive metabolite of psilocybin which mediates i...
Effects of serotonin 2A/1A receptor stimulation by psilocybin on mood and emotion processing in major depressive disorder: a randomized double-blind placebo-controlled study Major depressive disorder (MDD) is one of the world's greatest contributor to the global burden of disease and MDD affects around 17% of the Swiss population (Tomonaga et al. 2013). It i...
Introdução: A depressão é um transtorno psiquiátrico caracterizado por episódios agudos ou recorrentes de humor deprimido e perda de interesse ou prazer, levando a prejuízos funcionais ao paciente. A psilocibina é uma droga psicodélica com propriedades alucinógenas e serotoninérgicas derivada de cogumelos do gênero Psilocybe. Estudos recentes demonstram pote...
The concept of self and self-referential processing has a growing explanatory value in psychiatry and neuroscience, referring to the cognitive organization and perceptual differentiation of self-stimuli in health and disease. Conditions in which selfhood loses its natural coherence offer a unique opportunity for elucidating the mechanisms underlying self-dis...
Psilocybin has recently attracted a great deal of attention as a clinical research and therapeutic tool. The aim of this paper is to bridge two major knowledge gaps regarding its behavioural pharmacology - sex differences and the underlying receptor mechanisms. We used psilocin (0.25, 1 and 4 mg/kg), an active metabolite of psilocybin, in two behavioural par...
Social ties are crucial for physical and mental health. However, psychiatric patients frequently encounter social rejection. Moreover, an increased reactivity to social exclusion influences the development, progression, and treatment of various psychiatric disorders. Nevertheless, the neuromodulatory substrates of rejection experiences are largely unknown. T...
The mixed serotonin (5-HT) 1A/2A/2B/2C/6/7 receptor agonist psilocybin dose-dependently induces an altered state of consciousness (ASC) that is characterized by changes in sensory perception, mood, thought, and the sense of self. The psychological effects of psilocybin are primarily mediated by 5-HT2A receptor activation. However, accumulating evidence sugge...
BackgroundRecent findings suggest that the serotonergic system and particularly the 5-HT2A/1A receptors are implicated in visual processing and possibly the pathophysiology of visual disturbances including hallucinations in schizophrenia and Parkinson's disease.MethodsTo investigate the role of 5-HT2A/1A receptors in visual processing the effect of the hallu...
Binocular rivalry refers to the fluctuations in visual awareness/suppression that occur when different images are simultaneously presented to each eye. To explore the role of serotonin (5-HT) in binocular rivalry, this study investigated the affects of the hallucinogenic 5-HT1A&2A receptor agonist psilocybin (the active compound in “magic mushrooms”), alone ...
Increasing evidence suggests a link between attention, working memory, serotonin (5-HT) and prefrontal cortex activity. In an attempt to tease out the relationship between these elements, this study tested the effects of the hallucinogenic 5-HT1A/2A receptor agonist psilocybin alone and after pretreatment with the 5-HT2A antagonist ketanserin on multiple obj...
N,N-dipropyltryptamine (DPT) is a synthetic tryptamine hallucinogen which has been used psychotherapeutically in humans, but has been studied preclinically only rarely. In the present studies, DPT was tested in a drug-elicited head-twitch assay in mice, and in rats trained to discriminate lysergic acid diethylamide (LSD), N,N-dimethyl-4-phosphoryloxytryptami...