Fig. 1.  Effects of gabazine on γ-aminobutyric acid (GABA)ergic inhibitory synaptic and extrasynaptic currents in the substantia gelatinosa neurons. (A ) In the presence of strychnine (2 μm), bath application of gabazine (1 μm) completely abolished inhibitory postsynaptic currents (boxes a  and b ) without any changes in baseline current. In contrast, the application of bicuculline (20 μm) evoked a slow inward current (box c ). The holding membrane potential was 0 mV. (B ) Two consecutive traces in the expanded time scale in boxes a  (control) and b  (gabazine), indicating the suppression of inhibitory postsynaptic currents by gabazine (1 μm). (C ) Baseline currents in 30 s of box a  (control), box b  (gabazine), and box c  (gabazine with bicuculline) in fig. 1A. The dashed lines  indicate the averages of the each baseline current. Corresponding all-points histograms are shown (d ). (D ) Relative baseline shifts produced by gabazine (−1.5 ± 1.3 pA) and bicuculline (−9.5 ± 3.2 pA, n = 6, *P < 0.05).