Quantification of the cross-sectional area of CaV1.3 immunofluorescence revealed approx. 34 % smaller clusters in 1-SKOs and 24 % smaller clusters in 1/3-DKOs. (Wt n = 153/ N = 2; 1-SKO n = 102/ N = 2; 1/3-DKO n = 441/ N = 4; ***p < 0.0001; K-W and Dunn's post-hoc test). 