Fig. 1. Sensitivity of K+ currents to TEA and 4-AP. (A, C, E) Current responses to 200 ms voltage steps before, during and after application of 10 mM TEA and/or 4 mM 4-AP. Voltage steps from -104 to +36 mV in 10 mV increments, from a holding potential of -84 mV. External solution contained TTX (1 μM), CdCl2 (200 μM), ZD7288 (50 μM), and CNQX (10 µM). (B, D, F) Current voltage relations with and without TEA and/or 4-AP (mean±S.D.) after leak subtraction. Current amplitudes were measured at the time marked by vertical dotted lines (20 or 195 ms into the voltage steps). (G) The TEA sensitive current was calculated as the difference of currents measured in control and TEA as shown in B. (H) The 4-AP sensitive current was calculated as the difference of currents measured in control and 4-AP as shown in D. (I) The 4-AP sensitive and the 4-AP resistant and TEA sensitive currents were calculated as the difference of currents measured in control, 4-AP, and 4-AP + TEA as shown in F. A change in the steepness of the functions in B and G (arrows) suggests two components of TEA sensitive current. *Significant difference between control vs. TEA or control vs 4-AP. #Significant difference between 4-AP vs. 4-AP+TEA.
© Exp Neurobiol
