Figure 1.

Effects of K_v7-acting drugs on oxygen and glucose deprivation (OGD)-induced dopamine (DA) efflux. (A) Representative experiments showing dopamine efflux elicited by OGD in the presence of vehicle (top trace) and 1 μmol/L retigabine (bottom trace); the arrow indicates the onset of dopamine efflux. The inset shows the cyclic voltammogram obtained by plotting the faradaic current against the input voltage. Faradaic currents are obtained by subtracting the signal recorded at the carbon fiber electrode in the absence of dopamine from the signal in the presence of dopamine. Peaks due to the oxidation (OX) and reduction (RED) of dopamine are indicated. (B and C) Effects of K_v7 activators (B: retigabine, ICA27243 and NS15370) and blockers (C: XE-991 and linopirdine) on time to onset, time to peak, maximum extracellular dopamine concentration, and mean rate of dopamine efflux. (D) Effects of 1 μmol/L retigabine alone (black columns) or coincubated with 10 μmol/L linopirdine (white columns) on dopamine efflux parameters. Data are expressed as percentage of DMSO-treated slices (controls, represented by the dashed line). Values are mean±s.e.m. of 5 to 9 slices from 5 to 6 rats. *P<0.05.