Schizophr Res
November 1, 2005
Shitij Kapur, Romina Mizrahi, Ming Li
510 citations
Psychosis may arise from the brain incorrectly assigning novelty and importance to ordinary objects and associations, a process linked to dopamine's role in reward prediction and motivational salience. Antipsychotics block dopamine receptors, reducing this aberrant salience and creating a state of detachment from symptoms rather than eradicating them. Contrary to the idea of a delayed onset, improvement is evident within the first few days. The framework accounts for existing data and questions assumptions about antipsychotic action, including their effects in animal models, where they dampen both aberrant and normal motivational salience.
Neuron
September 25, 2024
Ming Li, Xue-Ke Yang, Jian Yang et al.
30 citations
Traumatic memories from social defeat stress in mice are stored in engram cells of the basolateral amygdala (BLA). A single low dose of ketamine given during, but not after, a brief re-exposure to the trauma context reduces social avoidance behavior. This effect lowers both the activity and number of reactivated BLA engram cells. Dopamine projections from the ventral tegmental area to the BLA, acting through dopamine D2 receptors, can mimic or block the therapeutic effect. Single-cell RNA sequencing shows that re-exposure with ketamine alters memory-related pathways in the BLA. The findings suggest a mechanism for how ketamine may alleviate PTSD symptoms and point to potential treatments for trauma-related disorders.
Medicine
November 1, 2024
Xiangqian Wan, Ming Li, Xiantao Li et al.
8 citations
A subclinical dose of esketamine (0.25 mg/kg) given after umbilical cord clamping during elective cesarean sections did not reduce the incidence of postpartum depression at 14 days postpartum, as measured by the Edinburgh Postnatal Depression Scale. However, it did significantly lower postoperative pain scores on the Visual Analog Scale at 4 and 24 hours after surgery. The treatment group experienced temporary increases in adverse reactions and sedation scores five minutes after administration. The findings suggest esketamine may offer short-term pain relief without preventing postpartum depression.
Behavioural brain research
September 15, 2015
Natashia Swalve, Scott T Barrett, Rick A Bevins et al.
Nicotine and phencyclidine (PCP) each separately increased rats' lever-pressing for a brief visual stimulus, indicating a reinforcement-enhancement effect. The effect was dose-dependent for nicotine (0.2 or 0.4 mg/kg) and present with PCP (2.0 mg/kg) across increasing fixed-ratio schedules. Adding PCP to nicotine did not further increase lever-pressing, possibly due to a ceiling effect. PCP's effect appeared driven largely by locomotor stimulation, whereas nicotine's effect was independent of locomotor activity. This dissociation suggests that different pharmacological properties underlie the reinforcement-enhancement effects of these substances.