Slow inactivation properties in HEK cells assessed with VC (A) and alternating VC/CC (B).

<p><b>a and b</b>, Top: voltage clamp (A) and VC/CC (B) protocols, with a conditioning prepulse interval (P1) of 10–1000 ms, as indicated, and a 30-ms interval to remove fast inactivation. Bottom: typical examples of slow inactivation with a conditioning prepulse of 1000 ms. <b>c</b>, Average development of slow inactivation. Note the logarithmic time scale. Solid lines are double-exponential fits to the average data.