Several recent studies have shown that a single intravenous subanesthetic dose of ketamine, a NMDA receptor antagonist, exerts rapid antidepressant effects in patients with treatment refractory mood disorders and reduces suicidal ideation. Those insights have fueled tremendous excitement in the efforts to elucidate the mechanism underlying ketamine's antidepressant properties in animal models...
For more than 50 years, ketamine has proven to be a safe anesthetic drug with potent analgesic properties. The active enantiomer is S(+)-ketamine. Ketamine is mostly metabolized in norketamine, an active metabolite. During "dissociative anesthesia", sensory inputs may reach cortical receiving areas, but fail to be perceived in some association areas. Ketamine also enhances the descending...
Several studies have documented impairments in memory processes as a result of ketamine administration; however, few studies have compared the profile of cognitive effects of ketamine to other drugs. The aim of this study was to compare the cognitive effects of ketamine with those of triazolam in healthy volunteers. Doses of ketamine (0.2, 0.4 mg/kg intramuscular (i.m.)), triazolam (0.2, 0.4...
The anaesthetic ketamine is used to treat various chronic pain syndromes, especially those that have a neuropathic component. Low dose ketamine produces strong analgesia in neuropathic pain states, presumably by inhibition of the N-methyl-D-aspartate receptor although other mechanisms are possibly involved, including enhancement of descending inhibition and anti-inflammatory effects at central...
BACKGROUND: Clinical studies demonstrate that the N-methyl-D-aspartate (NMDA) receptor antagonist, ketamine, induces rapid antidepressant effects in patients with refractive major depressive disorder and bipolar depression. This rapid onset of action makes ketamine a highly attractive drug for patients, particularly those who do not typically respond to therapy. A recent study suggested that...
Ketamine (Ketalar®) is an anesthetic agent derived from the hallucinogenic drug phencyclidine (PCP). It is a high-affinity antagonist at N-methyl-D-aspartate receptors and also binds to opioid mu and sigma receptors. Ketamine is being intensively investigated as an antidepressant therapy. To date, five short-term controlled studies and other open-label studies in patients with unipolar or...
The dissociative anesthetic ketamine has been subject to growing abuse worldwide, particularly in adolescents. This project compared the effects of ketamine in conditioned place preference and intravenous self-administration in adolescent (PND 28-50) and adult (>PND70) Sprague-Dawley rats. Cocaine served as a positive control. In CPP, adolescents demonstrated preferences for ketamine, while...
Excitatory-inhibitory imbalance has been identified within specific brain microcircuits in models of Rett syndrome (RTT) and other autism spectrum disorders (ASDs). However, macrocircuit dysfunction across the RTT brain as a whole has not been defined. To approach this issue, we mapped expression of the activity-dependent, immediate-early gene product Fos in the brains of wild-type (Wt) and...
The recreational use of ketamine is increasing in popularity due to its dissociative and paralytic effects, ease of availability and low cost. However, serious and frequently irreversible damage to the urinary tract is a recently recognised side effect of recreational ketamine use. The authors present a case of a young male patient with a 2-year history of troublesome lower urinary tract...
Increasing preclinical and clinical evidence underscores the strong and rapid antidepressant properties of the glutamate-modulating NMDA receptor antagonist ketamine. Targeting the glutamatergic system might thus provide a novel molecular strategy for antidepressant treatment. Since glutamate is the most abundant and major excitatory neurotransmitter in the brain, pathophysiological changes in...