title: Enrichment induces structural changes and recovery from nonspatial memory deficits in CA1 NMDAR1-knockout mice.
abstract: We produced CA1-specific NMDA receptor 1 subunit-knockout (CA1-KO) mice to determine the NMDA receptor dependence of nonspatial memory formation and of experience-induced structural plasticity in the CA1 region. CA1-KO mice were profoundly impaired in object recognition, olfactory discrimination and contextual fear memories. Surprisingly, these deficits could be rescued by enriching experience. Using stereological electron microscopy, we found that enrichment induced an increase of the synapse density in the CA1 region in knockouts as well as control littermates. Therefore, our data indicate that CA1 NMDA receptor activity is critical in hippocampus-dependent nonspatial memory, but is not essential for experience-induced synaptic structural changes.
authors.affiliation: Department of Molecular Biology, Princeton University, Washington Road, Princeton, New Jersey 08540-1014, USA.
authors.forename: C
authors.initials: C
authors.lastname: Rampon
authors.forename: Y P
authors.initials: YP
authors.lastname: Tang
authors.forename: J
authors.initials: J
authors.lastname: Goodhouse
authors.forename: E
authors.initials: E
authors.lastname: Shimizu
authors.forename: M
authors.initials: M
authors.lastname: Kyin
authors.forename: J Z
authors.initials: JZ
authors.lastname: Tsien
mesh_terms: D000818:Animals; D003213:Conditioning, Psychological / Q000502:physiology; D003463:Cues; D003712:Dendrites / Q000502:physiology / Q000648:ultrastructure; D004597:Electroshock; D005106:Exploratory Behavior / Q000502:physiology; D005239:Fear / Q000502:physiology; D005260:Female; D005518:Food Preferences / Q000502:physiology; D017774:Long-Term Potentiation / Q000502:physiology; D008297:Male; D008568:Memory / Q000502:physiology*; D008569:Memory Disorders / Q000235:genetics / Q000503:physiopathology; D051379:Mice; D018345:Mice, Knockout; D010364:Pattern Recognition, Visual / Q000502:physiology; D017966:Pyramidal Cells / Q000166:cytology / Q000254:growth & development / Q000502:physiology* / Q000648:ultrastructure; D016194:Receptors, N-Methyl-D-Aspartate / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D012903:Smell / Q000502:physiology; D013028:Space Perception / Q000502:physiology; D013569:Synapses / Q000502:physiology / Q000648:ultrastructure
chemical_list: D016194:Receptors, N-Methyl-D-Aspartate