Chronic oral ketamine prevents anhedonia and alters neuronal activation in the lateral habenula and nucleus accumbens in rats under chronic unpredictable mild stress.

Acute injections of ketamine lead to rapid but transient antidepressant effects. Chronic oral treatment at low doses, a promising non-invasive alternative, may prolong this therapeutic effect. Here, we examine the antidepressant effects of chronic oral ketamine in rats under chronic unpredictable mild stress (CUMS), and reveal their neuronal correlates.