Peduncular hallucinosis (PH) consists of formed and coloured visual images, which the patient knows are unreal; it is often associated with lesions of the pons, midbrain and diencephalon. A 72-year-old man had noted the sudden onset of visual hallucinations one year before, specifying the time and body position in a 4-week, 24-h diary. Thereafter, he underwent video-polysomnography (VPSG),...
Serotonin, a biogenic amine, is present in significant amounts in many structures of the CNS. It is involved in regulation of a wide variety of physiological functions, such as sensory and motor functions, memory, mood, and secretion of hormones including reproductive hormones. It has also been implicated in the etiology of a range of psychiatric disorders such as anxiety, depression, and...
J. Neurochem. (2009) 112 , 951–962. Abstract 3,4‐Methylenedioxymethamphetamine (MDMA; ‘Ecstasy’) is a popular recreational drug used worldwide. This study aimed to determine the effects of this compound on the expression of nerve terminal serotonergic markers in rats. Experiment 1 investigated MDMA‐induced changes in levels of the serotonin transporter (SERT) and the vesicular monoamine...
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...
The amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) reverses dopamine and serotonin transporters to produce efflux of dopamine and serotonin, respectively, in regions of the brain that have been implicated in reward. However, the role of serotonin/dopamine interactions in the behavioral effects of MDMA remains unclear. We previously showed that MDMA-induced locomotion,...
The 5-HT(2A) serotonin receptor is the most abundant serotonin receptor subtype in the cortex and is predominantly expressed in pyramidal neurons. The 5-HT(2A) receptor is a target of several hallucinogens, antipsychotics, anxiolytics, and antidepressants, and it has been associated with several psychiatric disorders, conditions that are also associated with aberrations in dendritic spine...
Recent experiments using non-selective 5-hydroxytryptamine (5-HT)(2C) receptor agonists including WAY 161503 suggested that midbrain 5-HT neurones are under the inhibitory control of 5-HT(2C) receptors, acting via neighbouring gamma-aminobutyric acid (GABA) neurones. The present study extended this pharmacological characterization by comparing the actions of WAY 161503 with the 5-HT(2C)...
There are high levels of comorbidity between neuropsychiatric and cardiovascular disorders. A key molecule central to both cognitive and cardiovascular function is the molecule serotonin. In the brain, serotonin modulates neuronal activity and is actively involved in mediating many cognitive functions and behaviors. In the periphery, serotonin is involved in vasoconstriction, inflammation, and...
The mechanism by which the recreational drug (+/-)-3,4-methylenedioxymethamphetamine (MDMA) destroys brain serotonin (5-HT) axon terminals is not understood. Recent studies have implicated MDMA metabolites, but their precise role remains unclear. To further evaluate the relative importance of metabolites versus the parent compound in neurotoxicity, we explored the relationship between...
3,4-Methylenedioxymethamphetamine (MDMA) is a drug of abuse worldwide and a selective serotonin (5-HT) neurotoxin. An important factor in the risk of drug abuse and relapse is stress. Although multiple parallels exist between MDMA abuse and stress, including effects on 5-HTergic neurotransmission, few studies have investigated the consequences of combined exposure to MDMA and chronic stress....
Ecstasy (MDMA, 3,4-methylendioxymethamphetamine) and the stimulants methamphetamine (METH, speed) and amphetamine are popular drugs among young people, particularly in the dance scene. When given in high doses both MDMA and the stimulant amphetamines are clearly neurotoxic in laboratory animals. MDMA causes selective and persistent lesions of central serotonergic nerve terminals, whereas...
Ecstasy or 3,4-methylenedioxymethamphetamine (MDMA) is a frequently (ab)used recreational drug for its acute euphoric effects but on the long-term may cause neurotoxic damage to serotonin (5-hydroxytryptamine; 5-HT) nerve endings in the brain. Since decreased brain 5-HT function has been strongly associated with several impulse control disorders like hostility and violent aggression, ecstasy...
N,N-dimethyltryptamine (DMT) is a potent plant hallucinogen that has also been found in human tissues. When ingested, DMT and related N,N-dialkyltryptamines produce an intense hallucinogenic state. Behavioral effects are mediated through various neurochemical mechanisms including activity at sigma-1 and serotonin receptors, modification of monoamine uptake and release, and competition for...
We propose a translational approach to the study of anorexia nervosa (AN) based on our human subject studies where there are characteristic elevations in 5-HT(1A) receptor binding, associated harm avoidance behaviors, reduced impulsivity, and comorbid anxiety disorders. Towards this goal, the hyponeophagia assay was implemented whereby food-deprived mice show increased latency to begin feeding...
Pyramidal neurons in layer 5 of the cerebral cortex are involved in learning and memory and have complex connections with other neurons through a very large array of dendrites. These dendrites can switch between long term depression and long term potentiation depending on global summation of various inputs. The plasticity of the input into pyramidal neurons makes the neuronal output variable....
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...
Here, we report that postsynaptic density protein of 95 kDa (PSD-95), a postsynaptic density scaffolding protein, classically conceptualized as being essential for the regulation of ionotropic glutamatergic signaling at the postsynaptic membrane, plays an unanticipated and essential role in mediating the actions of hallucinogens and atypical antipsychotic drugs at 5-HT 2A and 5-HT 2C...
A series of novel ligands for the serotonin 5-HT(2A/C) receptor subtype bearing the 2-phenylethylamine pharmacophore was synthesized and assayed for its 5-HT(2A) receptor binding affinity. As the 4'-aryl-substituted 2-(2,5-dimethoxyphenyl)ethylamines were previously unknown, an initial series of twelve compounds was chosen to obtain initial insight into their structure-activity relationships....
Background Animal experimental studies have prompted concerns that widespread use of 3,4-methylenedioxymethamphetamine (MDMA; ‘ecstasy’) by young people may pose a major public health problem in terms of persistent serotonin neurotoxicity. Aims To determine the status of brain serotonin neurons in a group of abstinent MDMA users. Method We assessed the integrity of brain serotonin neurons by...