title: The role of GluN2A and GluN2B subunits on the effects of NMDA receptor antagonists in modeling schizophrenia and treating refractory depression.
abstract: Paradoxically, N-methyl-D-aspartate (NMDA) receptor antagonists are used to model certain aspects of schizophrenia as well as to treat refractory depression. However, the role of different subunits of the NMDA receptor in both conditions is poorly understood. Here we used biochemical and behavioral readouts to examine the in vivo prefrontal efflux of serotonin and glutamate as well as the stereotypical behavior and the antidepressant-like activity in the forced swim test elicited by antagonists selective for the GluN2A (NVP-AAM077) and GluN2B (Ro 25-6981) subunits. The effects of the non-subunit selective antagonist, MK-801; were also studied for comparison. The administration of MK-801 dose dependently increased the prefrontal efflux of serotonin and glutamate and markedly increased the stereotypy scores. NVP-AAM077 also increased the efflux of serotonin and glutamate, but without the induction of stereotypies. In contrast, Ro 25-6981 did not change any of the biochemical and behavioral parameters tested. Interestingly, the administration of NVP-AAM077 and Ro 25-6981 alone elicited antidepressant-like activity in the forced swim test, in contrast to the combination of both compounds that evoked marked stereotypies. Our interpretation of the results is that both GluN2A and GluN2B subunits are needed to induce stereotypies, which might be suggestive of potential psychotomimetic effects in humans, but the antagonism of only one of these subunits is sufficient to evoke an antidepressant response. We also propose that GluN2A receptor antagonists could have potential antidepressant activity in the absence of potential psychotomimetic effects.
authors.affiliation: 1] Department of Neurochemistry and Neuropharmacology, Instituto de Investigaciones Biomédicas de Barcelona, CSIC, Barcelona, Spain [2] Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain [3] Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Jiménez-Sánchez
authors.affiliation: 1] Department of Neurochemistry and Neuropharmacology, Instituto de Investigaciones Biomédicas de Barcelona, CSIC, Barcelona, Spain [2] Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain [3] Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
authors.forename: Leticia
authors.initials: L
authors.lastname: Campa
authors.affiliation: Novartis Institutes for Biomedical Research, Basel, Switzerland.
authors.forename: Yves P
authors.initials: YP
authors.lastname: Auberson
authors.affiliation: 1] Department of Neurochemistry and Neuropharmacology, Instituto de Investigaciones Biomédicas de Barcelona, CSIC, Barcelona, Spain [2] Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain [3] Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
authors.forename: Albert
authors.initials: A
authors.lastname: Adell
mesh_terms: D000818:Animals; D000928:Antidepressive Agents / Q000494:pharmacology; D061218:Depressive Disorder, Treatment-Resistant / Q000188:drug therapy* / Q000503:physiopathology; D004195:Disease Models, Animal; D016291:Dizocilpine Maleate / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology*; D018698:Glutamic Acid / Q000378:metabolism; D008297:Male; D010636:Phenols / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology; D017397:Prefrontal Cortex / Q000187:drug effects / Q000503:physiopathology; D011810:Quinoxalines / Q000494:pharmacology; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*; D012559:Schizophrenia / Q000503:physiopathology; D012701:Serotonin / Q000378:metabolism; D013239:Stereotyped Behavior / Q000187:drug effects / Q000502:physiology
chemical_list: D000928:Antidepressive Agents; D016291:Dizocilpine Maleate; D018691:Excitatory Amino Acid Antagonists; D018698:Glutamic Acid; D010636:Phenols; D010880:Piperidines; D011810:Quinoxalines; D016194:Receptors, N-Methyl-D-Aspartate; D012701:Serotonin; C498554:5-(alpha-methyl-4-bromobenzylamino)phosphonomethyl-1,4-dihydroquinoxaline-2,3-dione; C121001:NR2B NMDA receptor; C109643:Ro 25-6981