Fig. 2

Statistical analysis of peptidome results of 4-AP treated and control samples. A Mean abundance distribution of binned data. B Square root of coefficient of variation (sqrtCV) distribution shows equal variations from high to low abundance peptides. C Sequence logo for all detected peptides show higher frequency for basic amino acids around the cleavage site. D Samples show higher correlation coefficients within experimental groups (Spearman’s correlation). E Length distribution of all, downregulated and upregulated peptides shows that upregulated peptides are shorter than downregulated one. F Volcano plot of detected peptides shows a high number of altered peptides in microdialysate upon 4-AP treatment. G Hierarchical clustering separated control and 4-AP treatment groups except for one sample. (n = 11, paired t-test; α = 0.05)