Behavioral pharmacology of N-methyl-D-aspartate antagonists: Implications for the study and pharmacotherapy of anxiety and schizophrenia

N-Methyl-D-aspartate (NMDA) antagonists have behavioral effects in animals that may have implications for treatment or understanding of anxiety and schizophrenia. Whereas the anxiolytic effects of NMDA antagonists in animal screening procedures may have direct therapeutic applications for the pharmacotherapy of anxiety disorders, the effects of these drugs in startle and drug discrimination procedures have indirect implications for the study of schizophrenia. For example, investigation of the interaction and shared activity of NMDA antagonists and dopamine agonists may aid in understanding the interaction of dopamine and glutamate systems in schizophrenia. In addition, this type of study may result in development of screening procedures for atypical antipsychotics useful in the treatment of schizophrenia resistant to pharmacotherapy with traditional antipsychotics. Finally, examination of the discriminative stimulus effects of NMDA antagonists may allow prediction of adverse subjective effects of potential medications of this class.