Fig. 2.
Mice lacking the CaMKIIδ phosphorylation site on RyR2 have a blunted FFR. (A) In vivo contractility as a function of pacing frequency. Contractility represented as percentage change in dP/dtmax from baseline (WT, n = 9; S2814A, n = 8; *P < 0.05). (B) Representative left ventricular pressure traces of ex vivo contractility data from Langendorff perfused hearts paced from 400 beats/min to 550 beats/min. (C) Pooled results of ex vivo contractility study for hearts paced from baseline heart rate of 400 beats/min to 550 or 700 beats/min represented as percentage change in dP/dtmax from baseline heart rate (WT, n = 13; S2814A, n = 9; S2808A, n = 4; WT + KN-93, n = 5; asterisk over KN-93 bar indicates significant difference vs. WT; *P < 0.01; **P < 0.05).