Figure 5.
Impairment of memory in APPE693Δ-Tg mice. Spatial reference memory of Tg mice was assessed by the Morris water maze at 8 months. A, Mice were trained to swim to the hidden platform for 6 consecutive days. Each point represents the mean latency of five trials per day ± SEM (n = 9 for APPE693Δ-Tg; n = 8 for NonTg and APPWT-Tg). The APPE693Δ-Tg mice exhibited significantly longer escape latencies than the APPWT-Tg mice and non-Tg littermates. The APPWT-Tg mice exhibited slightly, but not significantly, longer escape latencies than the non-Tg littermates. *p < 0.0001 versus NonTg; p = 0.0010 versus APPWT-Tg. B, At day 7, retention of memory was assessed by a probe trial for 30 s with the platform removed. Each bar represents the mean time occupancy ± SEM in the target quadrant (TQ), adjacent quadrants (AQ1, AQ2), or opposite quadrant (OQ). The APPE693Δ-Tg mice spent significantly shorter time in the target quadrant than the APPWT-Tg mice and non-Tg littermates did. *p = 0.0265 versus NonTg; p = 0.0149 versus APPWT-Tg.