LACK OF COGNITIVE IMPAIRMENTS IN APP-OVEREXPRESSING SW 2576 TRANSGENIC MICE

Summary and Conclusions • APP overexpressing transgenic Tg 2576 mice do show enhanced amyloid depositionand impaired performance in the water maze. However, the behavioural impairmentis Tg+ independent. • Both Tg+ and Tg- mice show behavioural anomalies such as spin-swimmingbehaviour. These aren’t always present, but may interfere with successful swimming.Regardless spin-swimmers are still capable of finding the submerged platform in thewater maze. • Tg+ and Tg- Tg 2576 mice are neurologically either no different from BL/6SJL F1 mice,or are both impaired relative to this background strain. Tg+ mice could bedifferentiated from Tg- in terms of (a) dark phase activity, (b) response rate for foodand water and (c) seizure susceptibility. • Tg+ and Tg- mice both show impaired cognitive abilities relative to BL/6SJL F1 micein learning a water maze procedure or responding to a lever. however, no suchimpaired cognitive impairments were noted in passive avoidance learning, Y-mazealternation or chained responding. Indeed, Tg+ mice proved to be more efficientresponders on operant tasks than either their Tg- or BL/6SJL