Electrophysiological effects of Ca_v1.2α_1C overexpression in mouse ventricular myocytes.

(A) Averaged peak current-voltage relationships demonstrate significant increase of I_Ca,L density at multiple depolarizing pulses in NFTG and FTG compared with NTG cardiomyocytes. The voltage protocol used to record I_Ca,L is shown in the inset. (B) Inactivation time constants (τ_fast and τ_slow) were determined from I_Ca,L traces depolarized to +10 mV fitted by double exponential equation: Y = Y_min+ A₁×[1−exp(−t/τ_fast)] + A₂×[1−exp(−t/τ_slow)], where Y is the fraction of recovery, A₁ and A₂ are the maximum values of the fast and slow component, and τ_fast and τ_slow are the time constants, respectively.