(a) Representative ICa,L recorded from ventricular myocytes isolated from WT, ACV KO, and ACVI KO, respectively. Current traces were elicited using a voltage step of 0 mV for 500 ms from a holding potential of -55 mV at baseline (blue) and after 20 minutes of ISO (red). The corresponding currentvoltage (IV) relations elicited using a family of voltage steps from -40 to +60 mV from a holding potential of -55 mV are shown to the right. (b) Schematic representation of the known regulation of ICa,L by β-AR stimulation. (c) Summary data of ICa,L density (in pA/pF) from the three groups of mice (n=8 for each group, *P<0.05).