Table 1.

Electrophysiological parameters

KCNQ subunit transfectedCurrent density (pA/pF)V1/2(mV)Slope (mV)TEA block IC50(mm)*n
None6  ± 2#−3  ± 0.4##10  ± 0.21.6  ± 0.25
2L50  ± 9*,$,&−25.5  ± 5%12  ± 10.14  ± 0.039
2L/2S, 1:137  ± 4&−28  ± 412  ± 10.2  ± 0.066
2L/2S, 1:515  ± 3*,#−18  ± 313  ± 10.55  ± 0.026
2S7  ± 2#−1.8  ± 2##9.5  ± 12.2  ± 0.49
3a36  ± 4$,@−40  ± 2^^ 11  ± 2456  ± 17
3/2S, 1:113  ± 2@,#−19  ± 2^^ 15  ± 17  ± 110
3/2S, 1:514  ± 1@,#−6  ± 5^^,##10  ± 20.65  ± 0.1210
2L/3, 1:1144  ± 27^−35  ± 3**14  ± 0.734  ± 15
2L/3/2S, 1:1:1137  ± 28^−38  ± 312  ± 28.4  ± 16
2L/3/2S, 1:1:5202  ± 20^−14  ± 3**,%12  ± 11.2  ± 0.65
  • All data were derived from experiments done in HEK293 cells. IC50 values for TEA blockade of KCNQ K+currents were estimated from responses to 0.1, 0.5, 1, 5, and 20 mM concentrations of drug applied during a 1 sec depolarizing step from −70 to 40 mV. Data were fit to the Hill equation (not shown), andK1/2 (IC50) values are tabulated. For Q3 and Q2L/Q3 (1:1) 50% inhibition by TEA was not achieved; therefore, reported IC50 values are at best estimates derived from the theoretical fit. Comparisons are among results with identical symbols:

  • p > 0.05, *p < 0.05, $p > 0.05, &p > 0.05, @p < 0.001, ^ p > 0.05, **p < 0.01, %p < 0.05,

  • p > 0.05, ^^ p < 0.001.

  • a3, Q3.