Fig. 3. Effects of midazolam on γ-aminobutyric acid (GABA)ergic inhibitory extrasynaptic currents in the presence of gabazine. (A ) After inhibitory postsynaptic currents were abolished by gabazine (1 μm) and strychnine (2 μm), midazolam (5 μm) was applied for 3 min. Slow outward current was induced by midazolam (dashed boxes a and b ). The holding membrane potential was 0 mV. (B ) The baseline currents for 30 s before (a , control) and during application of midazolam (b ). The horizontal dashed lines indicate the mean amplitude of the baseline currents. Corresponding all-points histograms are shown (c ). (C ) Dose dependence of the midazolam-induced outward current. EC50(effective concentration producing half-maximal response) was 2.1 ± 0.03 μm (n = 7 at each point).