Nature
October 18, 2023
Shuangshuang Ma, Min Chen, Yihao Jiang et al.
202 citations
Ketamine's antidepressant effects last much longer than its short half-life because the drug becomes trapped in NMDA receptors in the lateral habenula, and its release depends on neural activity. In mice, a single injection suppressed burst firing and blocked NMDA receptors in the lateral habenula for up to 24 hours. This sustained action results from use-dependent trapping, not endocytosis. By activating the lateral habenula and opening local NMDA receptors at different plasma ketamine concentrations, the duration of antidepressant effects could be shortened or prolonged. These findings explain the mechanism behind ketamine's sustained effects and suggest ways to modulate its therapeutic duration.
The International Journal of Neuropsychopharmacology
November 1, 2011
Giacomo Salvadore, Jan Willem van der Veen, Yan Zhang et al.
105 citations
Pretreatment levels of certain amino-acid neurotransmitters in the prefrontal cortex predict how well patients with major depressive disorder respond to a single intravenous infusion of ketamine. In fourteen drug-free patients, a lower ratio of glutamine to glutamate in the dorsomedial/dorsal anterolateral prefrontal cortex was associated with greater improvement in depressive symptoms 230 minutes after ketamine administration. Higher glutamate levels in the ventromedial prefrontal cortex correlated with greater improvement in anxiety symptoms. The findings suggest that the presence of reduced glial cells, reflected by the lower glutamine-to-glutamate ratio, may indicate which patients are more likely to benefit from ketamine treatment.
Psychiatry research
January 1, 2024
Wei Liu, Jing Yuan, Yun Wu et al.
19 citations
Mindfulness-based cognitive therapy (MBCT) reduced depression, anxiety, sleep problems, and inflammatory markers (IL-1β, IL-6, IL-8, TNF-α) while increasing mindfulness, self-compassion, and brain-derived neurotrophic factor (BDNF) in college students with major depressive disorder, compared with a wait-list group. Greater daily practice time and more session attendance were linked to larger reductions in depression, anxiety, and sleep difficulties. Completers showed significantly greater improvement than partial attendees, indicating a dose-response effect.
Scientific reports
November 6, 2024
Yan Zhang, Chu-Ke Wei, Ping Wang et al.
12 citations
Prenatal stress from unpredictable mild stress during pregnancy leads to depressive-like behaviors and impaired hippocampal neuroplasticity in male offspring. A single dose of S-ketamine (10 mg/kg) given to these offspring on postnatal day 42 counteracted depression-like behaviors. At the cellular level, S-ketamine alleviated reductions in neuronal complexity and dendritic spine density in the CA1 hippocampus and reversed synaptic morphology alterations. At the molecular level, it upregulated BDNF and PSD95 expression and activated AKT and mTOR in the hippocampus. S-ketamine appears to produce antidepressant effects by enhancing hippocampal neuroplasticity via the BDNF/AKT/mTOR signaling pathway.
International Journal of Surgery
September 23, 2025
Zhi-Yu Geng, Yan Zhang, Hui Bi et al.
1 citation
Adding a low dose of esketamine during surgery did not improve recovery quality, measured by the QoR-40 score, for patients undergoing laparotomy for gynecologic malignancy as part of a multimodal pain management plan. The result suggests no additional benefit from this intervention. More research is needed to determine whether different doses or patient groups might benefit.
Psychiatry research
August 1, 2023
Jin Liu, Xiaotian Zhao, Xiyu Wei et al.
A double-blinded, placebo-controlled randomized trial tested whether nitrous oxide (N2O) improves cognitive function in 44 patients with treatment-resistant depression. Thirty-four patients completed cognitive tests before treatment and at 1 and 2 weeks after a one-hour inhalation of 50% N2O/50% oxygen or placebo (50% air/50% oxygen). Although N2O did not produce a significant antidepressant effect at 1 week, patients who received N2O showed better executive function at 1 week compared with placebo, and this improvement remained after controlling for changes in depressive symptoms. No significant differences were found in subjective cognitive function, processing speed, or attention over the 2-week follow-up. The results suggest N2O may have a pro-cognitive effect on executive function independent of mood improvement.
Psychiatry Research
January 1, 2023
Xuexiao Shao, Danfeng Yan, Wenwen Kong et al.
In patients with treatment-resistant depression, a single 1-hour inhalation of nitrous oxide improved depressive symptoms more than a placebo, as measured by the 17-Hamilton Depression Rating Scale. The treatment altered brain function, shown by changes in event-related potential components (N1, P1, N2, P2) and increased functional connectivity networks. These brain changes correlated with symptom reduction, suggesting nitrous oxide works by modifying brain function.
Psychiatry research
November 1, 2022
Danfeng Yan, Bangshan Liu, Xiyu Wei et al.
A single one-hour inhalation of 50% nitrous oxide (N2O) mixed with oxygen rapidly alleviated depression in patients with treatment-resistant depression in China, but the effect lasted no more than one week. In a double-blind, placebo-controlled trial, 44 patients were randomized to receive either 50% N2O or a placebo mixture. Depression scores on the Hamilton Depression Rating Scale were significantly lower in the N2O group at two hours and 24 hours after treatment, but no significant difference remained at one week or two weeks. Patients receiving N2O reported more adverse events, all of which resolved within 24 hours, and no serious adverse events occurred.