HEK293 cells plated for 48 hours and then transfected with rat Slo27 for 24 hours. Currents from whole-cell recordings, with 1 µM Ca2+ in the electrode solution. Cells voltage-clamped at -80 mV, with currents activated by 500 ms depolarization to +20 mV. Concentration-inhibition relationship produces an IC50 of 412 pM.(Number of experimental determinations shown in brackets).