Ca2+-image study reveals suppression of glutamate-evoked elevation of cytoplasmic [Ca2+] in L100P mutant hippocampus. a Representative confocal images of CA1 pyramidal cells loaded with Fluo-4 AM (green) before (a, c) and during (b, d) perfusion with 50 μM glutamate. Bar 50 μm. b Time course of glutamate-induced intracellular [Ca2+] increase in CA1 pyramidal neurons. Fluorescence intensity changes ΔF was background corrected and normalized to the resting fluorescence (F0). The addition of glutamate was indicated by the horizontal bar (red). The grey vertical bars indicate the selective time points that images shown in A were taken. Traces represent averaged responses of selected cells in the same field of view. c Summary of glutamate-induced [Ca2+] elevations in CA1 pyramidal neurons of juvenile mice (P8 ~ P15). WT, n = 31 cells from 4 mice and L100P, n = 25 cells from 3 mice, * P < 0.05, unpaired t-test. d Summary of glutamate-induced [Ca2+] elevations in DG granule cells of juvenile mice (P8 ~ P15). WT, n = 22 cells from 4 mice and L100P, n = 15 cells from 3 mice, **P < 0.01, unpaired t-test. Data were averaged during 200–300 s after the onset of perfusion with glutamate, and normalized by the mean fluorescence intensity obtained during the baseline period (0–100 s) before glutamate perfusion for each cell. All data are shown as means ± SEM.