SYN1 and Alzheimer disease: The expression of synapsin 1 showed a decrease in the CA1 region (Fig. 5b and f; two-tailed Student’s t test, p = 0.0395), and a trend in the CA3 region (Fig. 5b, f; two-tailed Student’s t test, p = 0.07) and the parietal cortex (Fig. 5b and f; two-tailed Student’s t test, p = 0.06) in 3 × Tg-AD-vh compared to WT mice.