Recent studies have shown that ketamine, an open channel blocker of the N-methyl-d-aspartate receptor (NMDAR), is effective for patients with treatment-resistant depression. In this study, we aimed to elucidate the potential link between antidepressant-like effects of a single ketamine administration and dorsoventral differentiation in adult hippocampal neurogenesis. Immunohistochemical...
This study aimed to investigate the efficacy and safety of intermittent low-dose ketamine on improving the efficacy of ECT. Patients diagnosed with Major Depressive Disorder (MDD) (n = 134) were randomized into 3 groups: routine ECT group (group E, n = 45); repeated ketamine-assisted ECT group (group RK, n = 43), and intermittent ketamine-assisted ECT group (group IK, n = 46). Patients in group...
Abstract Subanesthetic administration of ketamine is a pharmacological model to elicit positive and negative symptoms of psychosis in healthy volunteers. We used resting‐state pharmacological functional MRI (rsPhfMRI) to identify cerebral networks affected by ketamine and compared them to the functional connectivity (FC) in schizophrenia. Ketamine can produce sedation and we contrasted its...
Like its predecessor intravenous ketamine, an anesthetic that has been used off‐label to treat depression, esketamine has shown great promise in treating a disease that can destroy quality of life and lead to suicide. The Food and Drug Administration (FDA) approved esketamine (Spravato) last spring for treating depression that is resistant to traditional treatments.
INTRODUCTION: Recreational ketamine abuse can present with a unique constellation of symptoms, and limited literature on this topic makes this case a rare learning opportunity. CASE DESCRIPTION/METHODS: A 37-year-old male with diffuse psoriasis and a one-year-history of ketamine inhalation presented to the ER complaining of recurrent episodes of epigastric pain. The pain was described as...
Treatment resistant depression is a common and burdensome condition with poor outcomes and few treatment options. Approximately one third of patients with major depressive disorder are treatment resistant to the current antidepressants. In addition, depression in patients with bipolar disorder is typically poorly responsive to antidepressants. And so, there is an unmet need for rapidly acting...
Subanesthetic rather than anesthetic doses are thought to bring the rapid antidepressant effects of the NMDAR (N-methyl-d-aspartate receptor) antagonist ketamine. Among molecular mechanisms, activation of BDNF receptor TrkB along with the inhibition of GSK3β (glycogen synthase kinase 3β) are considered as critical molecular level determinants for ketamine's antidepressant effects....
A five‐week trial involving 55 participants has concluded that a single infusion of ketamine in combination with a course of mindfulness‐based psychotherapy was more effective than midazolam with therapy in limiting craving and maintaining abstinence among individuals with cocaine dependence. The researchers found that participants receiving ketamine were 53% less likely to drop out of...
Ketamine’s antidepressant effects, previously thought to involve the NMDA receptor, may be produced through the opioid system (because blocking opiate receptors with naltrexone blocked the antidepressant effect).
CellsSeptember 24, 2019Alessandra Grossert, N. Mehrjardi, S. Bailey et al.
The N-methyl-D-aspartate (NMDA) receptor antagonist ketamine offers promising perspectives for the treatment of major depressive disorder. Although ketamine demonstrates rapid and long-lasting effects, even in treatment-resistant patients, to date, the underlying mode of action remains elusive. Thus, the aim of our study was to investigate the molecular mechanism of ketamine at clinically...
In resting-state functional connectivity experiments, a steady state (of consciousness) is commonly supposed. However, recent research has shown that the resting state is a rather dynamic than a steady state. In particular, changes of vigilance appear to play a prominent role. Accordingly, it is critical to assess the state of vigilance when conducting pharmacodynamic studies with resting-state...
Childhood maltreatment is associated with a poor treatment response to conventional antidepressants and increased risk for treatment-resistant depression (TRD). The N-methyl-D-aspartate receptor (NDMAR) antagonist ketamine has been shown to rapidly improve symptoms of depression in patients with TRD. It is unknown if childhood maltreatment could influence ketamine’s treatment response. We...
Initiation of ketamine use often occurs in adolescence, yet little is known about long-term consequences when use begins in this developmental period. The current experiments were designed to examine the effects of repeated exposure to ketamine in adolescence on behavior in adulthood. We examined locomotor activity, as well as cognitive function, in animals that received repeated administration...
Esketamine nasal spray in combination with a newly initiated antidepressant was more effective than a new antidepressant plus placebo in reducing depressive symptoms in patients with treatment‐resistant depression, a Phase 3 study has found. Esketamine, the S‐enantiomer of ketamine, recently received Food and Drug Administration (FDA) approval for treatment‐resistant depression in adults. Study...
Ketamine has been shown to induce a rapid antidepressant effect on patients with depression. In many animal models, both rapid and sustained antidepressant activities were also found in response to an antagonist of group II metabotropic glutamate receptors, LY341495, and its mechanism of action seemed to be similar in many ways to the action of ketamine. It has also been found that LY341495...
BACKGROUND: A recent study demonstrated that spine formation rates by ketamine in the prefrontal cortex (PFC) were not altered at 3-6 h following a single injection, but were markedly altered at 12-24 h. Here, we investigated the acute (3 h post-treatment) effects of (R)-ketamine in the decreased spine density in the medial PFC (mPFC) and hippocampus in susceptible mice after chronic social...
Background: Introduction: The average person has up to 15% lifetime risk for developing depression. Major depressive disorder symptoms can include a depressed mood, such as feeling sad or having more anger than normal, changes in appetite, loss of interest in activities or hobbies, psychomotor agitation or retardation, loss of energy, feelings of worthlessness or guilt, decreased ability to...
1,2-Diarylethylamines represent a class of molecules that have shown potential in the treatment of pain, epilepsy, neurodegenerative disease and depression. Examples include lefetamine, remacemide, and lanicemine. Recently, several 1,2-diarylethylamines including the dissociatives diphenidine, methoxphenidine and ephenidine as well as the opioid MT-45, have appeared as 'research chemicals' or...
Discovering that the anesthetic drug ketamine has rapidly acting antidepressant effects in many individuals with major depression is one of the most important findings in clinical psychopharmacology in recent decades. The initial report of these effects in human subjects was based on a foundation of rodent preclinical studies carried out in the 1990s, and subsequent investigation has included...
Objective It is recognised that ketamine treatment can reduce suicidal ideation (SI) in people with depression, at least in the short term. However, information is lacking on patients’ perspectives on such effects. Studying these can contribute to greater understanding of the mechanisms underlying impact of ketamine treatment on SI. The aim of this study was to investigate patients’ reports of...