Animal and clinical studies have demonstrated that ketamine has quick, obvious and persistent antidepressant-like effect, but such side effects as cardiovascular system excitement and hallucinogenic activity have limited its clinical application. Intravenous anesthetic propofol can remarkably inhibit or eliminate ketamine's side effects including cardiovascular system excitement and...
Interactions between glutamatergic and endocannabinoid systems may contribute to schizophrenia, dissociative states, and other psychiatric conditions. Cannabidiol (CBD), a cannabinoid-1/2 (CB1/2) receptor weak partial agonist or antagonist, may play a role in the treatment of schizophrenia. This study tested the hypothesis that CBD would attenuate the behavioral effects of the NMDA receptor...
Psychiatry ResearchJanuary 12, 2011Gerald W Valentine, G. Mason, R. Gomez et al.
The NMDA receptor antagonist ketamine can induce a rapid improvement in depressive symptoms that often endures for days after a single intravenous dose. The pharmacodynamic basis for this effect is poorly understood. Using a proton magnetic resonance spectroscopy ([1H]-MRS) method that previously detected a normalization of amino acid neurotransmitter (AANt) content after chronic treatment with...
Use of ketamine as a recreational drug is spreading rapidly among young people all over the world. Epidemiological studies have linked chronic ketamine use with a number of problems, including cognitive impairments, bladder dysfunction, and ketamine-related death. However, little is known about the long-term effects of ketamine use on brain structure and function. We used voxel based...
Some patients with major depressive disorder remain resistant to antidepressant medication. A randomized, placebo-controlled, double-blind trial demonstrated that a single subanesthetic dose (0.5 mg/kg) of the N-methyl-D-aspartate receptor antagonist ketamine caused a rapid antidepressant effect within hours in treatment-resistant patients with major depressive disorder. However, the precise...
PLoS One2011María Jesús Nicolás, Jon López-Azcárate, Miguel Valencia et al.
Oscillatory activity can be widely recorded in the cortex and basal ganglia. This activity may play a role not only in the physiology of movement, perception and cognition, but also in the pathophysiology of psychiatric and neurological diseases like schizophrenia or Parkinson's disease. Ketamine administration has been shown to cause an increase in gamma activity in cortical and subcortical...
Major mood disorders have been linked to abnormalities in circadian rhythms, leading to disturbances in sleep, mood, temperature, and hormonal levels. We provide evidence that ketamine, a drug with rapid antidepressant effects, influences the function of the circadian molecular machinery. Ketamine modulates CLOCK:BMAL1-mediated transcriptional activation when these regulators are ectopically...
Ketamine was developed in the early 1960s as an anesthetic and has been used for medical and veterinary procedures since then. Its unique profile of effects has led to its use at subanesthetic doses for a variety of other purposes: it is an effective analgesic and can prevent certain types of pathological pain; it produces schizophrenia-like effects and so is used in both clinical studies and...
Background Our sense of body ownership is profound and familiar, yet it may be misleading. In the rubber-hand illusion, synchronous tactile and visual stimulation lead to the experience that a rubber hand is actually one's own. This illusion is stronger in schizophrenia. Given the evidence that ketamine, a noncompetitive N-methyl-D-aspartate antagonist reproduces symptoms of schizophrenia, we...
Misattribution of distorted self-generated speech in patients with schizophrenia has been associated with increased lateral temporal activation. As a pharmacological model of schizophrenia, we tested whether ketamine would induce the same effects in healthy individuals. Participants were 8 healthy male volunteers who were naïve to ketamine (mean age: 28 years). Ketamine (0.23 mg/kg bolus...
AIMS: This study was designed to evaluate the changes in EEG power spectra and EEG coherence in a ketamine model of psychosis in rats. Analyses of behavioral measurements--locomotion and sensorimotor gating--and the pharmacokinetics of ketamine and norketamine were also conducted. METHODS: Ketamine and norketamine levels in rat sera and brains were analyzed by gas chromatography-mass...