Figure 2.

Currents through T-type Ca²⁺ channels in fusion-competent myoblasts. Ba²⁺ (10 mM) was used as a charge carrier. (A) The cell was held steadily at −90 mV and stepped to values between −70 mV and +30 mV for 80 ms. Peak T-currents were plotted in the absence (squares) and in the presence of 300 μM amiloride (circles). Leak current was estimated by adding 1 mM Cd²⁺ and was subtracted. (Inset) Voltage step to −20 mV. (B) Another cell. Voltage step to −10 mV. Ni²⁺ (50 μM) also blocks T-channels.