Table 1.

Effect of ET-1 on activation and inactivation of TTX-R and TTX-S sodium channels in rat DRG neurons

Activation curve*Availability curve**
E0.5(mV)ka (mV)h0.5(mV)kh (mV)
TTX-R
 Control cells (n = 6)
  Baseline−14.49 ± 1.295.59 ± 0.72−24.75 ± 0.44a4.76 ± 0.02
  10 min−16.67 ± 1.356.13 ± 0.70−25.67 ± 0.535.29 ± 0.00
  20 min−14.11 ± 0.875.95 ± 0.67
  Δ[10 min − baseline]−2.17 ± 0.421.03 ± 0.54−0.92 ± 0.090.53 ± 0.02
 ET-1 responsive cells (n = 10)
  Baseline−18.94 ± 1.425.39 ± 0.25−27.26 ± 1.485.33 ± 0.10
  ET-1−26.98 ± 1.344.64 ± 0.27−32.44 ± 1.506.02 ± 0.29
  Δ[ET-1 − baseline]−8.04 ± 0.540.75 ± 0.27−5.18 ± 0.370.69 ± 0.26
 ET-1 non-responsive cells (n = 7)
  Baseline−13.33 ± 2.205.93 ± 0.45−20.57 ± 0.35b5.33 ± 0.03
  ET-1−15.58 ± 2.344.64 ± 0.27−22.81 ± 0.385.93 ± 0.04
  Δ[ET-1 − baseline]−3.25 ± 0.180.07 ± 0.17−2.24 ± −0.030.60 ± 0.03
 BQ-123 plus ET-1-treated cells (n = 10)
  Baseline−10.27 ± 1.856.67 ± 0.36−23.55 ± 1.856.41 ± 0.34
  BQ-123−12.34 ± 1.845.94 ± 0.37−25.12 ± 2.026.51 ± 0.56
  BQ-123 plus ET-1−13.93 ± 1.906.13 ± 0.24−29.05 ± 2.116.63 ± 0.38
  Δ[BQ-123 − baseline]−2.07 ± 0.611.54 ± 0.45−1.85 ± 0.500.13 ± 0.30
  Δ[(BQ-123 + ET-1) − BQ-123]−1.54 ± 0.450.19 ± 0.17−2.90 ± 0.350.07 ± 0.26
TTX-S (n = 7)
  Baseline−14.49 ± 1.295.59 ± 0.72−24.75 ± 0.444.76 ± 0.02
  ET-1−16.67 ± 1.355.95 ± 0.67−25.67 ± 0.535.29 ± 0.01
  Δ[ET-1 − baseline]−2.17 ± 0.421.03 ± 0.54−0.92 ± 0.090.53 ± 0.02
  • All values listed are means ± SEM. *Boltzmann equation for fitting the activation curve is as follows:G/Gmax = {1 + exp[−(EE0.5)/ka]}−1. **Boltzmann equation for fitting the availability curve is as follows:I/Imax = (AmaxA0)/{1 + exp[(h0.5E)/kh]} +A0.

  • F1-a n = 4.

  • F1-b n = 4.