Figure 1.

(A,B) Effects of bepridil on the outward current of a guinea-pig ventricular myocyte. Current families in the absence (A) and presence (B) of 10 μM bepridil. (C) Current-voltage relationship of bepridil-sensitive time-dependent current. The ordinate shows the difference in the time-dependent current at the end of the depolarizing pulses (abscissa), measured between corresponding traces in panels A and B. The lack of an apparent inward-going rectification in the I–V curve suggests that bepridil blocked the slowly activating component of the delayed-rectifier K⁺ current, i.e., I_Ks. The L-type Ca²⁺ current was blocked by 1 μM D600. Temperature, 35°C.