Figure 2.

Steady-state stimulation with the CHF AP increased Ca²⁺ entry, SR Ca²⁺ content, and Ca²⁺ transient magnitude, and maintained Ca²⁺ release synchrony. (A) Normal cardiomyocytes were stimulated with trains of identical APs. (Lower panels) Representative spatially averaged Ca²⁺ transients. (B) Line-scan images of Ca²⁺ transients and mean dyssynchrony index measurements. (C) Representative I_LCC and mean integrated currents elicited by the SHAM and CHF APs. (D) Estimation of SR Ca²⁺ content based on the magnitude of caffeine-elicited Ca²⁺ transients. For panels B–D, n = 7, 9, 25; P < 0.05 versus SHAM AP.