Figure 6. MyBP‐C phospho‐ablation blunts the adrenergic mediated enhancement of diastolic relaxation .

A, ventricular pressure relaxation in WT and TnI^PKA− mice is accelerated by β‐adrenergic activation, although this acceleration is blunted in MyBPC^PKA‐ and DBL^PKA− mice. Black traces represent baseline LV developed pressure during diastolic relaxation, whereas grey traces represent post‐dobutamine pressure relaxation. MyBP‐C phospho‐ablation also blunts the β‐adrenergic mediated acceleration of the relaxation time constant (Tau, B), the decrease in the slope of the pressure trace from 50% to 25% of maximal pressure (C) and the peak filling rate (PFR, normalized to end diastolic volume) (D). All values in (B) to (D) are represented as the values at the peak dobutamine response minus baseline values. Values are expressed as the mean ± SEM from seven to 10 mice per line. *Significantly different from WT (P < 0.05).