title: Spatial memory performance and hippocampal neuron number in osteoporotic SAMP6 mice.
abstract: The senescence-accelerated mouse strain P6 (SAMP6) is an inbred mouse that represents a clinically relevant model of senile osteoporosis. However, whether osteoporotic SAMP6 mice have cognitive deficits remains largely unexplored. Here, we used Morris water maze to assess reference memory and working memory performance in SAMP6 mice and SAMR1 controls, at 4 and 8 months of age. In addition, unbiased stereological techniques were used to estimate total neuron number in hippocampal CA1 subfield of the mice used in the behavioral study. Morris water maze test revealed impairments in working memory but not in reference memory of the 4- and 8-month-old SAMP6 mice compared with the SAMR1 mice at the same age. However, there were no significant differences in the total numbers of neurons in hippocampal CA1 subfield when comparing 4-month-old SAMR1 and 4-month-old SAMP6 and 8-month-old SAMR1 and 8-month-old SAMP6, which indicate that, in SAMP6 mice, the structural correlates of working memory deficits are to be found in parameters other than the number of neurons in hippocampal CA1 subfield. These findings suggest that SAMP6 mice exhibit selective cognitive deficits and highlight the importance of this mouse model for studying the brain alterations associated with osteoporosis.
authors.affiliation: Medical Molecular Biology Laboratory, Gerontological Department, The First Hospital affiliated to Tianjin University of Traditional Chinese Medicine, Tianjin, China. lcz623780@126.com
authors.forename: Cun-Zhi
authors.initials: CZ
authors.lastname: Liu
authors.forename: Jian-Chun
authors.initials: JC
authors.lastname: Yu
authors.forename: Hai-Yan
authors.initials: HY
authors.lastname: Cheng
authors.forename: Zhi-Guo
authors.initials: ZG
authors.lastname: Jiang
authors.forename: Tan
authors.initials: T
authors.lastname: Li
authors.forename: Xue-Zhu
authors.initials: XZ
authors.lastname: Zhang
authors.forename: Lin-Lin
authors.initials: LL
authors.lastname: Zhang
authors.forename: Jing-Xian
authors.initials: JX
authors.lastname: Han
mesh_terms: D000367:Age Factors; D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D002452:Cell Count; D003072:Cognition Disorders / Q000209:etiology / Q000503:physiopathology; D004195:Disease Models, Animal; D006624:Hippocampus / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D018782:Maze Learning / Q000502:physiology; D008568:Memory / Q000502:physiology*; D051379:Mice; D008815:Mice, Inbred Strains; D009474:Neurons / Q000473:pathology*; D010024:Osteoporosis / Q000150:complications / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000502:physiology; D013037:Spatial Behavior / Q000502:physiology*; D013047:Specific Pathogen-Free Organisms; D013550:Swimming