Effects of Kihi-to on Aβ(25–35)-induced expression changes of calpain and calpastatin. Cortical neurons were cultured for 2 days and then treated with or without (C) 10 μM Aβ(25–35). The cells were simultaneously treated with Kihi-to (0.1 μg/ml, K), MDL28170 (1 nM, M), or vehicle (V) for 2, 8, 24 and 96 h, and then double-immunostained for calpain and MAP2 or for calpastatin and MAP2. Expression levels of calpain (A) and calpastatin (B) in MAP2-positive cells (neurons) were quantified. *p < 0.05 vs. Veh, n = 40. (one-way ANOVA followed by Holm-Sidak post hoc test).