title: NMDA receptors mediate consolidation of contextual memory in the hippocampus after context preexposure.
abstract: Male Wistar rats received bilateral infusions of vehicle (VEH) or aminophosphonopentanoic acid (AP5), an N-metil-D-aspartate (NMDA) receptor antagonist, into the dorsal hippocampus immediately after inhibitory avoidance (IA) training. Intrahippocampal infusion of AP5 blocked 24 h IA retention. In the second experiment, animals were preexposed to the IA training context 24 h prior to training and received an infusion of either VEH or AP5 immediately after the preexposure trial and a second infusion of VEH or AP5 immediately after IA training. AP5 did not affect retention in animals preexposed to the IA box and given VEH after preexposure, but blocked retention when given after both preexposure and training. AP5 impaired retention in rats preexposed to an environment distinct from the IA box. These results suggest that NMDA receptors in the dorsal hippocampus mediate the formation of a contextual representation of the task environment.
authors.affiliation: Preclinical Neuropharmacology Research Group, Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite, 500, 90046-900, Porto Alegre, RS, Brazil. rroesler@terra.com.br
authors.forename: Rafael
authors.initials: R
authors.lastname: Roesler
authors.forename: Gustavo K
authors.initials: GK
authors.lastname: Reolon
authors.forename: Tatiana
authors.initials: T
authors.lastname: Luft
authors.forename: Márcio R
authors.initials: MR
authors.lastname: Martins
authors.forename: Nadja
authors.initials: N
authors.lastname: Schröder
authors.forename: Mônica R M
authors.initials: MR
authors.lastname: Vianna
authors.forename: João
authors.initials: J
authors.lastname: Quevedo
mesh_terms: D015763:2-Amino-5-phosphonovalerate / Q000378:metabolism; D000818:Animals; D001362:Avoidance Learning / Q000502:physiology*; D018691:Excitatory Amino Acid Antagonists / Q000378:metabolism; D006624:Hippocampus / Q000033:anatomy & histology / Q000502:physiology*; D008297:Male; D008568:Memory / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*
chemical_list: D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D015763:2-Amino-5-phosphonovalerate