Figure 3.

Effect of Cd^{2 +} on inward currents and on regenerative responses induced by current injection in the presence of K ⁺ channel blockers. (A) Inward currents were evoked by voltage pulses in the presence of K⁺ channel blockers from a holding potential of –70 mV in 10-mV increments in control (left) and in the same cell after addition of Cd²⁺ (right). (B) Voltage responses were obtained on the same cell under current clamp conditions using the current protocols indicated below, in the presence of a control external medium (left), and in the presence of a solution containing 20 mM TEA and 3 mM 4-AP (right). The internal potential was held at –70 mV by passing a constant negative current. The star shows the voltage response obtained after addition of 500 μM Cd²⁺ in the external solution.