We investigated the potential role of the opioid system in modulating glutamatergic effects of ketamine administration in major depressive disorder. Twenty-six adults with major depressive disorder participated in a double-blind crossover study, receiving oral placebo or 50 mg naltrexone before an intravenous infusion of 0.5 mg per kg ketamine. Brain glutamatergic activity in the anterior...
Abstract Background Cannabis use has been associated with psychosis through exposure to delta-9-tetrahydrocannabinol (Δ9-THC), its key psychoactive ingredient. Although preclinical and human evidence suggests that Δ9-THC acutely modulates glial function and hypothalamic-pituitary-adrenal (HPA) axis activity, whether differential sensitivity to the acute psychotomimetic effects of Δ9-THC is...
AbstractThe associative striatum, an established substrate in psychosis, receives widespread glutamatergic projections. We sought to see if glutamatergic indices are altered between early psychosis patients with and without a history of cannabis use and characterise the relationship to grey matter. 92 participants were scanned: Early Psychosis with a history of cannabis use (EPC = 29); Early...
Both chronic cannabis use and psychotic disorders are associated with abnormalities in visual attentional processing. Using functional magnetic resonance imaging (fMRI), we sought to determine whether there would be a difference in functional connectivity in patients and controls with and without a history of cannabis use in the visual and dorsal attention networks. Resting-state fMRI data were...