Ketamine has anesthetic, analgesic, and antidepressant properties which may involve multiple neuromodulatory systems. In humans, the opioid receptor (OR) antagonist naltrexone blocks the antidepressant effect of ketamine. This mechanism may differentiate ketamine from other NMDA receptor antagonists. Animal models that reflect OR-dependent behavioral effects of ketamine may shed light on the...
Recent studies in mouse models have demonstrated that ketamine and rapastinel induce rapid-acting and sustained antidepressant effects in major depressive disorder (MDD). However, it remains unclear how ketamine's and rapastinel's opposing mechanisms of action-NMDAR antagonist and NMDAR positive allosteric modulator, respectively-result in similar antidepressant-like effects. Furthermore,...
Pharmacological management of major depressive disorder has traditionally relied on antidepressants targeting the monoaminergic pathway. Treatment-resistant depression (TRD) patients have been frequently excluded from registrational trials, resulting in a lack of clear clinical recommendations for an optimised management. In recent years, treatments based on other mechanisms of action have been...
MedicineMay 2, 2025Xiaobo Bi, Junchao Dai, Jin Li8 citations
This study aimed to investigate the effects of a single intravenous injection of esketamine during general anesthesia on postoperative anxiety and depression in patients with thyroid cancer. In this randomized, double-blind, placebo-controlled, parallel-group trial, eighty female patients with thyroid cancer were scheduled to undergo surgery under general anesthesia. The patients were randomly...
Ketamine has garnered attention for its rapid efficacy in alleviating depressive symptoms in treatment-resistant depression, offering a novel mechanism as a non-monoaminergic agent. Despite its potential, limited research has explored mental health professionals' perspectives on its use. This study assesses the attitudes, knowledge, and concerns of Portuguese psychiatrists and psychologists...
SUMMARYThis critical appraisal of a Cochrane Review assesses the efficacy of ketamine for treating unipolar major depressive disorder. The review included 31 randomised controlled trials involving ketamine. Results indicate that intravenous (i.v.) ketamine significantly improves antidepressant response compared with i.v. saline and, to a lesser extent, i.v. midazolam within 24–72 h. However,...
We previously reported that a single injection of (R,S)-ketamine or its metabolite (2S,6S)-hydroxynorketamine (HNK) prior to stress attenuated learned fear. However, whether these drugs attenuate learned fear through divergent or convergent effects on neural activity remains to be determined. 129S6/SvEv male mice were injected with saline, (R,S)-ketamine, or (2S,6S)-HNK 1 week before a 3-shock...
Ketamine's use in treating bipolar depression must account for risks, such as switching to manic episodes or worsening symptoms. This study examines ketamine's impact on depressive symptoms, focusing on 'inner tension,' 'sleep reduction,' and 'suicidal ideation' over four weeks in treatment-resistant bipolar disorder (TR-BD) patients. Fifty-nine patients with TR-BD were treated consecutively...
Depression is a common and serious psychiatric disorder with significant impacts on individuals. Modified electroconvulsive therapy (MECT) is an established treatment for severe and treatment-resistant depression, but its cognitive side effects, particularly memory impairments, limit its use. Esketamine (ESK), an FDA-approved antidepressant, has shown neuroprotective effects. However, its role...
Abnormalities during rapid eye movement (REM) sleep contribute to the pathophysiology of major depressive disorder (MDD), but few studies have explored the relationship between REM sleep and treatment-resistant depression (TRD). In MDD, REM sleep abnormalities often manifest as alterations in total night REM Density (RD), RD in the first REM period (RD1), and REM Latency (RL). Among these, RD1...