INHIBITION BY NONCOMPETITIVE NMDA RECEPTOR ANTAGONISTS OF APOMORPHINE-INDUCED CLIMBING BEHAVIOR IN MICE

The N-methyl-D-aspartate (NMDA) subtype of glutamate receptors is an i mportant mediator of several forms of neural and behavioral plasticity . In the present study, we examined the potential role of NMDA recepto rs in the glutamatergic modulation of dopaminergic function at the pos tsynaptic dopamine receptor by determining the effects of NMDA antagon ists on apomorphine-induced climbing behavior in mice. The noncompetit ive NMDA receptor antagonists, MK-801, ketamine, dextrorphan, and dext romethorphan attenuated the apomorphine-induced climbing behavior at d oses well below those that produce untoward side effects. These result s suggest that the NMDA receptors play important roles in the glutamat ergic modulation of dopaminergic function at the postsynaptic dopamine receptors that mediate the apomorphine-induced climbing behavior in m ice.