Figure 5. Accelerated currents are sensitive to block by dihydropyridine antagonist.

A, control currents (no prepulse) recorded in the absence (left) and presence (middle) of nifedipine (3 μM). DHP-sensitive control currents (right) exhibited slow activation kinetics typical of skeletal L-currents. B, accelerated currents (60 s +40 mV, 10 s repriming to -80 mV) recorded in the absence (left) and presence (middle) of nifedipine (3 μM). DHP-sensitive currents (right) exhibited accelerated activation kinetics following brief recovery (10 s at -80 mV) from prolonged depolarization.