Figure 5: Deletion of Rer1 resulted in severe impairment of spontaneous action potential generation and decreased amplitude of resurgent currents in Purkinje cells.

(a) PCs in cerebellar slices of 6–7 weeks old control (ctrl) and Rer1^ΔPC mice were patch-clamped in the loose cell-attached mode and high frequency firing was recorded. n, number of cells from 5 ctrl and 4 Rer1^ΔPC animals as indicated. Typical recordings for control and Rer1^ΔPC cells are shown, respectively. (b) Percentage of spontaneously firing PCs from recordings from a). (c) Mean firing frequency from recordings of PCs from a) including non-spiking cells (+) or excluding them (−). Non-spiking cells were defined as PCs identified by their morphology and typical low membrane resistance measured by establishment of whole cell configuration after cell attached recordings. Displayed is the mean frequency ±SD, Student’s t-test: p = 0.042; n = 20/11. Ctrl refers to Rer^fl/fl/cre^−/− littermates. (d) Representative voltage clamp traces of resurgent sodium currents after subtraction of recordings with tetrodotoxin from recordings without tetrodotoxin recorded from PCs in cerebellar slices of 7–8 weeks old control and Rer1^ΔPC mice. (e) Current-voltage relationship of resurgent sodium currents from (d). n, number of cells from 5 ctrl and 5 Rer1^ΔPC mice; two way ANOVA, p < 0.05.