BDS-1 (1 µM) reversibly inhibited UV-activated K+ currents in HCLE cells exposed to 80 mJ/cm2 UV-B. From a holding potential of −80mV, voltage steps of 250 ms duration were given in +10 mV intervals. UV-activated K+ currents were substantially larger than control currents within a minute after UV-B exposure. A. Current traces of a representative cell before UV-B exposure, 5 minutes after UV-B exposure before BDS-1 application, during BDS-1 application and after BDS-1 washout. B. Current-voltage (I-V) relationship of the same cell showing average currents before UV-B exposure (black), after UV-B exposure prior to drug application (violet), during BDS-1 (red), and during washout (blue).