Fig. 1

Chronic treatment with J4 alleviates the impairment of spatial memory and hippocampal CA1 LTD in Tau22 mice. a–d Mice were treated as indicated (WTC, black; WTJ, blue; TauC, red; TauJ, green; n = 12–20 in each group) from the age of 3–10 months. The Morris water maze (MWM) with a hidden platform was used to assess spatial learning and memory. a The acquisition-learning phase (Day 1–Day 5) and the reversal-learning phase (Day 9–Day 12) of MWM. *p < 0.05 versus the WTC group; ^#p < 0.05 versus the TauC group; two-way ANOVA. Probe tests for b the spatial memory and c spatial reversal memory were performed on Day 8 and Day 15, respectively. The average percentage of time spent in the T (target quadrant) and NTs (nontarget quadrants) were calculated. *p < 0.05 versus the NTs; two-tailed Student’s t-test. d The swimming speed (cm/s) of the animals in the probe test. e–h Hippocampal slices were prepared from mice subjected to different treatment groups (n = 3–18 slices from 3 to 8 mice in each group) from the age of 3–10 months. e The input/output relationship curve (fEPSP responses, stimuli strengths increased from 10 to 120 μA), f averaged paired-pulse ratios (interstimulus intervals, from 50 to 500 ms), and g, h Long-term depression (LTD) induced by 3 trains of LFS (2 Hz, 1200 pulses) at the Schaffer collateral-CA1 synapses were recorded. g The average fEPSP slopes of mice subjected to different treatments were calculated. *p < 0.05 versus the WTC group; ^#p < 0.05 versus the TauC group, two-way ANOVA. h Quantification results of the mean fEPSP slopes during the last 10 min of the steady-state period. *p < 0.05 versus the WTC group; ^#p < 0.05 versus the TauC group, one-way ANOVA. The data are expressed as means ± S.E.M