Figure 2.

GYY4137 inhibits recombinant Kv2.1. (A) Families of currents evoked in a HEK293 cell stably expressing Kv2.1 before and during exposure to GYY4137 (30 μM). Currents were evoked by step-depolarizations, applied up to + 80 mV in 10 mV increments from a holding potential of -70 mV. Scale bars apply to both families of currents. (B) Mean (± s.e.m.) current–density versus voltage relationships obtained in 11 cells before (solid circles) and during (open circles) exposure to GYY4137 (30 μM). Significance: *P < 0.05; **P < 0.01 as compared with controls. (C) Example time-series plot illustrating normalized current amplitudes evoked by step-depolarizations in a Kv2.1-expressing HEK293 cell. For the period indicated by the horizontal bar, GYY4137 (30 µM) was applied via the perfusate, indicated by horizontal bar, followed by washout. Inset shows example currents under the different experimental conditions scale bars: 2 nA (vertical) and 10 ms (horizontal). (D) Mean (± s.e.m., each point taken from 3 to 5 cells) concentration–response relationship fitted to sigmoidal Boltzmann function illustrating the effects of GYY4137 on Kv2.1. Inhibition was determined using currents evoked by step-depolarizations from − 70 to + 50 mV.