Figure 2.

ISO Reduces cBIN1 and Disrupts cBIN1-Microfolds, Which Is Normalized by AAV9-cBIN1

(A) Western blots of cBIN1 and GAPDH from heart lysates and immunoprecipitated heart lysates from GFP+PBS, GFP+ISO, cBIN1+PBS, and cBIN1+ISO hearts. Quantification in the bar graph to the right (N = 6–7 hearts per group). (B) Representative cardiomyocyte images with Di-8-ANNEPs labeling (top panel) (Scale bar, 10 μm) and power spectrum (bottom panel) of the corresponding boxed region of interest above. Quantification of peak power density is included in the bar graph to the left (N = 26 to 31 cells from 3 to 4 hearts per group). Data are presented as mean ± SEM. Two-way ANOVA was used followed by Fisher LSD test for multiple comparison. ∗p < 0.05 and ∗∗p < 0.01 for PBS vs. ISO comparison within each AAV9 treatment group; #p < 0.05 and ##p < 0.01 for GFP vs. cBIN1 comparison within each drug infusion group. (C) Transmission electron microscopy imaging of t-tubule (TT) microfolds from myocardial tissue from all 4 groups (scale bar, 1 μm). Quantitation of the degree of contour of TTs from each group is included in the bar graphs to the left (N = 232 to 305 TTs from 60 to 100 images of 5 to 6 myocardial sections and 2 to 3 hearts from each group). Chi-square test was used to compare TT contour between groups, p < 0.001 for comparison of GFP+PBS vs. GFP+ISO, GFP+ISO vs. cBIN1+ISO, and cBIN1+PBS vs. other groups. Di-8-ANNEPs = 4-[2-[6-(Dioctylamino)-2-naphthalenyl]ethenyl]-1-(3-sulfopropyl)-pyridinium, inner salt; GAPDH = glyceraldehyde 3-phosphate dehydrogenase; TTs = t-tubules; other abbreviations as in Figure 1.