Figure 1.

Na⁺ current families were recorded in Hek293t cells expressing either μ1-wild-type (A) or μ1-N434K channels (B) under reversed Na⁺ gradient conditions. Cells were dialyzed by internal solution for 10 min, and current traces were superimposed from −70 to +80 mV at 10-mV step. With 5 μM BTX in the pipette, repetitive pulses (Lower) were applied at 2 Hz and current traces of μ1-wild-type (C) or μ1-N434K channels (D) were superimposed. The pulse numbers are labeled; 30 p represents the 30 pulses applied to monitor Na⁺ currents during cell dialysis.