Background: A growing body of preclinical research suggests that brain glutamate systems
may be involved in the pathophysiology of major depression and the mechanism of action of
antidepressants. This is the first placebo-controlled, double-blinded trial to assess the
treatment effects of a single dose of an N-methyl-d-aspartate (NMDA) receptor antagonist in
patients with depression. Methods: Seven subjects with major depression completed 2 test
days that involved intravenous treatment with ketamine hydrochloride (. 5 mg/kg) or saline …