Table 1.
Effect of CyPPA on selected ion channels
| Ion channel | Cell type | Result (μM) |
|---|---|---|
| KCa1.1 (BK) | HEK293 | IC50=5.5±1.3 (n=6) |
| Kv7.2+7.3 (KCNQ2+3) | HEK293 | No effect at 30 (n=3) |
| Kv11.3 (hERG) | HEK293 | No effect at 10 (n=4) |
| Nav1.2 | HEK293 | IC50=10±1.9 (n=3) |
| Voltage-dependent K+ | DRG | IC50=68±8.8 (n=5) |
| Voltage-dependent Na+ | DRG | IC50=11±0.48 (n=3) |
| Voltage-dependent Ca2+ | DRG | No effect at 10 (n=3) |
Abbreviations: BK, large conductance Ca2+-activated K+ channel; CyPPA, cyclohexyl-[2-(3,5-dimethyl-pyrazol-1-yl)-6-methyl-pyrimidin-4-yl]-amine; DRG, dorsal root ganglion; HEK, human embryonic kidney; hERG, human ether-a-go-go-related gene; IC50, half-maximal inhibitory concentration.
CyPPA was tested in whole-cell voltage-clamp experiments using standard experimental protocols using recombinant ion channels stably expressed in HEK293 cells or endogeneously expressed channels in isolated DRG neurons. IC50 values were calculated from the blocker kinetics, assuming that IC50=Kd=(koff) (kon)−1, as described in Strøbæk et al. (2006).