文章基本信息

标题：Specific spatial learning deficits become severe with age in β-amyloid precursor protein transgenic mice that harbor diffuse β-amyloid deposits but do not form plaques
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作者：Milla Koistinaho ; Michael Ort ; Jose M. Cimadevilla 等
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2001
卷号：98
期号：25
页码：14675-14680
DOI：10.1073/pnas.261562998
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Memory impairment progressing to dementia is the main clinical symptom of Alzheimer's disease (AD). AD is characterized histologically by the presence of {beta}-amyloid (A{beta}) plaques and neurofibrillary tangles in specific brain regions. Although A{beta} derived from the A{beta} precursor protein ({beta}-APP) is believed to play a central etiological role in AD, it is not clear whether soluble and/or fibrillar forms are responsible for the memory deficit. We have generated and previously described mice expressing human wild-type {beta}-APP751 isoform in neurons. These transgenic mice recapitulate early histopathological features of AD and form A{beta} deposits but no plaques. Here we describe a specific and progressive learning and memory impairment in these animals. In the Morris water maze, a spatial memory task sensitive to hippocampal damage, one pedigree already showed significant differences in acquisition in 3-month-old mice that increased in severity with age and were expressed clearly in 6-month- and 2-year-old animals. The second transgenic pedigree displayed a milder impairment with a later age of onset. Performance deficits significantly decreased during the 6 days of training in young but not in aged transgenic animals. Both pedigrees of the transgenic mice differed from wild-type mice by less expressed increase of escape latencies after the platform position had been changed in the reversal experiment and by failure to prefer the goal quadrant in probe trials. Both pedigrees performed at wild-type level in a number of other tests (open field exploration and passive and active place avoidance). The results suggest that plaque formation is not a necessary condition for the neuronal {beta}-APP751 transgene-induced memory impairment, which may be caused by {beta}-APP overexpression, isoform misexpression, or elevated soluble A{beta}.