A and B, consecutive traces illustrating mIPSCs in control (A) and KA-pretreated (5 μm, 48 h) (B) neurons. Similar to the effect of CTZ, KA pretreatment also resulted in a marked decrease of the frequency of mIPSCs. C, the average frequency of mIPSCs was significantly decreased after chronic KA pretreatment (control, 2.3 ± 0.4 Hz; after KA treatment, 0.99 ± 0.18 Hz; **P < 0.005). D, the average amplitude of mIPSCs did not change significantly after KA pretreatment (25.0 ± 1.3 pA in control; 21.4 ± 1.6 after KA-pretreatment; ***P > 0.09).