MK‐801 produces antianxiety effect in elevated plus‐maze in mice

Abstract The antianxiety effect of the non‐competitive NMDA receptor antagonist, MK‐801, was investigated in the present study in the elevated plus‐maze paradigm in mice. During a 5‐min session of the test, the number of entries the animal made in open/and closed arm, preference of the animal for first entry, and average time each animal spent in open and closed arm were noted as parameters for anxiety‐related movements. The effect of MK‐801 was further explored by studying its interaction with the specific anxiolytic agent, diazepam; the anxiogenic beta carboline agent, FG 7142; and the central benzodiazepine receptor antagonist, flumazenil (RO 15–1788). MK‐801 produced anxiolytic effects at all the doses investigated. It increased the preference of the animal for open arm in a dose‐dependent manner and the effect was potentiated by diazepam. Both FG 7142 and flumazenil reversed the effects of MK‐801 when these agents were concomitantly administered with MK‐801. The study revealed the anxiolytic effect of MK‐801, a non‐competitive antagonist of NMDA‐receptor, and also an interaction of the NMDA‐receptor and GABA/BZ‐receptor complex in anxiety‐related behaviour in mice.