Figure 4.

RDX reduced the frequency and amplitude of GABA_A receptor–mediated sIPSCs in the BLA; whole-cell recordings from principal neurons in the BLA were obtained in the presence of CNQX, AP-5, and SCH50911. (A) sIPSCs recorded at V_h = +40 mV. The outward currents were reduced in both frequency and amplitude by bath application of 30 μM RDX (black bar over the current trace) and recovered partially after 12-min washout of RDX. The recovered currents were completely blocked by the GABA_A receptor antagonist bicuculline (20 μM; data not shown). (B) sIPSCs recorded at V_h = −70 mV. Bath-applied RDX (30 μM) reduced both the frequency and the amplitude of the inward currents. After 12-min washout of RDX, sIPSCs recovered only partially. Bath-applied bicuculline (20 μM) blocked the spontaneous currents. The lower row illustrates example current traces at an expanded time scale from control recording (one asterisk), in RDX (two asterisks), and after washout of RDX (three asterisks). (C) Decrease in the frequency of high-amplitude events (the threshold was set at 20 pA) by RDX. (D) Decrease in amplitude of sIPSCs in the presence of RDX (bin width, 10 pA; n = 4 slices/cells).

^#p < 0.05 by paired t-test.