Figure 4.

Efsevin Reduces Intracellular Ca²⁺ Spark Frequency, Amplitude, and Cytosolic Ca²⁺ Clearance Leading to a Restriction of Individual Ca²⁺ Sparks

(A) Representative line scan confocal images from RyR2^R4496C/WT cardiomyocytes show spontaneous Ca²⁺ sparks. (B) Treatment with ISO induced a higher spark frequency and amplitude and accelerated cytosolic Ca²⁺ removal (tau_decay) leading to narrower (full width) and shorter (full duration) sparks. Administration of efsevin reduced Ca²⁺ spark frequency (p = 0.049, Kruskal Wallis test) and amplitude (p < 0.001, Kruskal Wallis test) and limited spatial (p < 0.001, Kruskal Wallis test) and temporal (p = 0.002, Kruskal Wallis test) expansion of Ca²⁺ sparks. *p < 0.05; **p < 0.01; ***p < 0.001. Abbreviations as in Figure 1.