Altered navigational strategy use and visuospatial deficits in hAPP transgenic mice

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• 作者：Amy R. deIpolyi ; Shanna Fang ; Jorge J. Palop ; Gui-Qiu Yu ; Xin Wang ; Lennart Mucke
• 关键词：Alzheimer's disease ; Spatial memory ; Navigation ; Hippocampus ; Striatum ; Mouse model ; Aβ ; peptide ; Strategy ; Human amyloid precursor protein ; hAPP
• 刊名：Neurobiology of Aging
• 出版年：2008
• 出版时间：February 2008
• 年：2008
• 卷：29
• 期：2
• 页码：253-266
• 全文大小：1287 K

文摘

Navigation deficits are prominent in Alzheimer's disease (AD) patients and transgenic mice expressing familial AD-mutant hAPP and Aβ peptides. To determine the impact of strategy use on these deficits, we assessed hAPP and nontransgenic mice in a cross maze that can be solved by allocentric (world-based) or egocentric (self-based) strategies. Most nontransgenic mice used allocentric strategies, whereas half of hAPP mice were egocentric. At 3 months, all mice learned the cross maze rapidly; at 6 months, only allocentric hAPP mice were impaired. At 3 and 6 months, hAPP mice had reduced hippocampal Fos expression, which correlated with cross maze learning in older mice. Striatal pCREB expression was unaltered in hAPP mice, suggesting striatal sparing. We conclude that egocentric strategy use may be an earlier indicator of hAPP/Aβ-induced hippocampal impairment than spatial learning deficits. Persistent use of allocentric strategies when egocentric strategies are available is maladaptive when there is hippocampal damage. Interventions promoting flexibility in selecting learning strategies might help circumvent otherwise debilitating navigational deficits caused by AD-related hippocampal dysfunction.