Figure 3.

Effects of OM, EMD and Levo on the kinetics of cardiomyocyte contractions and relaxations. The durations of contractions (A) were progressively prolonged by increasing OM concentrations but remained unchanged during EMD or Levo administrations. The kinetics of contractions (B) were slowed down by higher OM concentrations (0.3 and 1 μM). Relaxation speeds of (E) were also greatly diminished by these high OM concentrations (C). Intracellular Ca²⁺ transient durations (D) were unaffected by all treatments. The kinetics of the upstrokes of intracellular Ca²⁺ transients (E) did not change during the treatments. Intracellular Ca²⁺ concentration transient decays (represented by the rate constant, K) (F) remained also unaltered during drug treatments. Significant differences are indicated by asterisks when P < 0.05 vs. before treatment. EMD, EMD‐53998; FI, fluorescence intensity; Levo, levosimendan; OM, omecamtiv mecarbil.