Figure 1.

Dfe Was an Inhibitor of Kv2.1 Channel

SP6616 or GxTx-1E (GE) was used as a positive control.

(A) Chemical structure of Dfe.

(B) CHO-Kv2.1 cell was incubated with SP6616 (20 μM) or GxTx-1E (GE, 100 nM) and membrane potential dye for 30 min, and signal was recorded. Data were shown as area under the curve (AUC). N = 6. SP6616 versus DMSO by Student's t test: ∗∗∗p < 0.001. GE versus DMSO by Student's t test: ∗∗∗p < 0.001.

(C) CHO-Kv2.1 cell was incubated with SP6616 (20 μM) or Dfe (5, 10, 20 μM) and membrane potential dye for 30 min, and signal was recorded. Data were shown as area under the curve (AUC). N = 3. SP6616 versus DMSO by Student's t test: ∗p < 0.05. Dfe (5, 10, 20 μM) versus DMSO by one-way ANOVA with Dunnett's post hoc test: F (3, 8) = 29.5. ∗∗p < 0.01; ∗∗∗p < 0.001.

(D) Membrane potential assay in CHO cell was conducted using the similar procedure to that in CHO-Kv2.1 cell. N = 6. SP6616 versus DMSO by Student's t test: ns. Dfe (5, 10, 20 μM) versus DMSO by one-way ANOVA with Dunnett's post hoc test: F (3, 20) = 0.2102. ns.

(E) Effect of Dfe (5, 10, 20 μM) on cell viability in CHO-Kv2.1 cell was detected by MTT assay. N = 6. Dfe (5, 10, 20 μM) versus DMSO by one-way ANOVA with Dunnett's post hoc test: F (3, 20) = 0.9416. ns.

(F) The whole-cell patch-clamp technique was used to detect the inhibitory effect of different concentrations of Dfe on Kv2.1 current in different cells, and the current curve of CHO-Kv2.1 cell was recorded.

(G) The electrophysiological data of multiple concentrations of Dfe on the same cell. N = 5. Dfe (1, 3, 10 μM) versus DMSO by one-way ANOVA with Dunnett's post hoc test: F (3, 16) = 41.48. ∗∗∗p < 0.001.

(H) The 50% inhibitory concentration (IC50) of Dfe at 9.53 μM was detected by whole-cell patch-clamp technique. N = 4–9. All data were presented as means ± SEM.