Figure 3

K⁺ currents in Tet-free conditions were carried by the transfected channel. Currents illustrated in panels A and C were recorded from CHO cells maintained in Tet-free media for 7 days. (A) Block of wild-type Kv2.1 and the channel mutant, Kv2.1 K356G K382V, by 3 mM TEA. The two traces in 0 TEA illustrate the control and recovery currents. (B) Mean block by 3 mM TEA in the two channel types, expressed in CHO cells exposed to Tet-free media for 7 days and in HEK cells, transiently transfected with channels. (C) Currents recorded from cells containing Kv2.1 (left) or Kv2.1 K356G K382V (right), in control solution (0 external K⁺) and following addition of 10 mM external K⁺ (equimolar substitution for NMG). (D) Mean change in current magnitude, normalized to the control current, following application of 10 mM external K⁺. In the experiments utilized for panels B and D, the mean current amplitude in CHO cells in 0 mM external K⁺ was 75 ± 13 pA (n = 10); current magnitudes in HEK cells ranged from 1 – 6 nA (data from [6] and [10]).