Fig. 5.

Quantification of synaptic protein levels using Western Blot. a, b Representative Western Blot of 2-7-week old WT and TgCRND8 slices probed for RT97 (phosphorylated neurofilament), Tuj1, Synaptophysin (SYP) and VAMP2 (a) or PSD95 and Tuj1 (b). c Synaptophysin levels (normalised to Tuj1) are decreased in TgCRND8 relative to WT (two way ANOVA p < 0.0001). There is a trend to this difference increasing with culture age (two way ANOVA p = 0.054), with 6 and 7-week old TgCRND8 cultures showing the greatest deficiency in synaptophysin (two way ANOVA multiple comparisons p < 0.05). d VAMP2 is also decreased in TgCRND8 cultures (two way ANOVA p = 0.0017) although the relationship with age is not clear (p = 0.23). There is no alteration in the levels of phosphorylated neurofilament (p = 0.91) (e) or PSD95 (p = 0.53) (f) demonstrating the losses seen are likely specific to presynaptic compartments. The large bar at the top of each graph displays tabular results from the two way ANOVA whilst individual bars on the graph show significant multiple comparisons. N numbers are written in the base of each bar, and represent the number of individual membranes (consisting of 3 slices extracted together and run in a single gel lane) from different mice