Fig. 2

Liraglutide (100 nM) enhanced sIPSC frequency and amplitude in a subpopulation of CA3 pyramidal neurons. Liraglutide significantly enhanced the frequency of sIPSCs only at 100 nM (c, n = 23) but not 1 nM (a, n = 8), 10 nM (b, n = 6) or 1 μM (d, n = 12) (Wilcoxon matched-pairs signed rank test: *p < 0.05). Data are presented as • for control and ■ for drug application, and each connecting line indicates an individual cell. Cumulative probability histograms revealed no significant change of sIPSC amplitudes before (solid lines) and after (dash lines) the application of 1 nM (e, n = 8), 10 nM (f, n = 6), 100 nM (g, n = 23) and 1 μM (h, n = 12) liraglutide. (i) The normalized frequency of sIPSCs in control for each liraglutide concentration is shown by the horizontal dash line and the effects of the different concentration as a scatter dot plot (○) with a mean and a box-and-whiskers plot with median values plotted by Tukey method for detecting the outliers (•) above or below the box-and-whiskers plot. Statistical analyses were performed after outlier exclusion. One-way ANOVA Bonferroni post hoc test, multiple comparisons versus control group, *p < 0.05 for 100 nM liraglutide. Neurons in 100 nM liraglutide were grouped according to increase in frequency after liraglutide application, (j) > 20%, (k) < 20%, Wilcoxon matched-pairs signed rank test: *p < 0.05, n = 13. (l), (m) Cumulative probability histograms of sIPSC amplitudes of the corresponding subgroups of neurons from (j) and (k) exposed to100 nM liraglutide application. Solid and dash lines indicate cumulative probability histogram of sIPSCs before and after application of 100 nM liraglutide, respectively. Wilcoxon matched-pairs signed rank test: *p < 0.05, n = 13