LAUSR

It is reported that dopamine D 1 receptors in the medial prefrontal cortex play a role in the antidepressant actions of ( R,S )-ketamine. However, its role in the antidepressant actions of ( R )-ketamine, which is more potent than ( S )-ketamine, is unknown. In the locomotion test, tail suspension test, forced swimming test and 1% sucrose preference test, pretreatment with dopamine D 1 receptor antagonist SCH-23390 did not block the antidepressant effects of ( R )-ketamine in the susceptible mice after chronic social defeat stress. These findings suggest that dopamine D 1 receptors may not play a major role in the antidepressant actions of ( R )-ketamine.