Figure 6.

Endogenous L-type currents from cardiomyocytes treated with AngII. (A) Representative whole-cell endogenous L-type Ca²⁺ current traces from cardiomyocytes control (upper traces) or treated with AngII (1 µM) for 1 hr (lower traces). Currents elicited by a voltage step protocol from –60 mV to + 50 mV in 10 mV increments, V_h = −80 mV. (B) Summary peak current I/V plots (mean ± sem) obtained from currents family as shown in (A), black line represents the best fit to a Bolztman equation (see methods). (C) Voltage-dependence of the activation time constant (τ_act, mean ± sem) of L-type Ca²⁺ currents (D) Graph showing the residual current after 50 ms of the depolarization pulse (R₅₀, mean ± sem) versus command voltage of L-type Ca²⁺ currents. Faster inactivation rates result in lower R₅₀ values. (E) Concentration-response curve of AngII-induced L-type calcium current reduction in rat cardiomyocytes, the line correspond to the best fit to Hill equation, mean values ± sem are shown. In every panel, control rat cardiomyocytes are represented with empty circles and rat cardiomyocytes treated with AngII with filled circles. (n = 4–10) *p < 0.01 with respect to control.