Comparison of outward current in OBNs and HEK 293 cells. A, Inactivation kinetics of OBN outward current immediately (t = 0 min) and 10 min after (t = 10 min) achieving the whole-cell recording configuration. B, Inactivation kinetics of Kv1.3 current in a cell-attached patch on a HEK 293 cell and 10 min after detaching in the inside-out patch configuration. For both A andB, the peak currents are normalized to better visualize the inactivation kinetics. C, Plot of the normalized peak outward current amplitude in an OBN 10 min after application of the indicated concentration of MgTx to the bath. Each point represents the mean for three to four cells; currents were normalized to the initial current for each cell. D, Kv1.3 currents in a cell-attached patch on a HEK 293 cell evoked by a depolarizing voltage step from −90 to +40 mV at the indicated times after achieving a gigaohm seal. 100 pm MgTx was present in the patch electrode.