title: Hippocampal function is not required for the precision of remote place memory.
abstract: BACKGROUND
  During permanent memory formation, recall of acquired place memories initially depends on the hippocampus and eventually become hippocampus-independent with time. It has been suggested that the quality of original place memories also transforms from a precise form to a less precise form with similar time course. The question arises of whether the quality of original place memories is determined by brain regions on which the memory depends.
  
  
  RESULTS
  To directly test this idea, we introduced a new procedure: a non-associative place recognition memory test in mice. Combined with genetic and pharmacological approaches, our analyses revealed that place memory is precisely maintained for 28 days, although the recall of place memory shifts from hippocampus-dependent to hippocampus-independent with time. Moreover, the inactivation of the hippocampal function does not inhibit the precision of remote place memory.
  
  
  CONCLUSIONS
  These results indicate that the quality of place memories is not determined by brain regions on which the memory depends.
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Graduate School of Medicine & Pharmaceutical Sciences, University of Toyama, Toyama 930-0194, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kitamura
authors.forename: Reiko
authors.initials: R
authors.lastname: Okubo-Suzuki
authors.forename: Noriko
authors.initials: N
authors.lastname: Takashima
authors.forename: Akiko
authors.initials: A
authors.lastname: Murayama
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Hino
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Nishizono
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kida
authors.forename: Kaoru
authors.initials: K
authors.lastname: Inokuchi
mesh_terms: D000818:Animals; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D004192:Discrimination, Psychological / Q000502:physiology; D006624:Hippocampus / Q000502:physiology*; D057567:Memory, Long-Term / Q000502:physiology*; D011939:Mental Recall / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D014176:Protein Biosynthesis; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D013997:Time Factors; D014158:Transcription, Genetic
chemical_list: C492004:Creb1 protein, mouse; D017362:Cyclic AMP Response Element-Binding Protein; D016194:Receptors, N-Methyl-D-Aspartate