Fig. 3.
Nociceptin inhibited evoked GABAergic IPSCs in a subpopulation of PAG neurons. Evoked IPSCs were produced by local stimulation in the presence of CNQX (10 μm). Shown is time course of the amplitude of evoked IPSCs (eIPSC) during the application of nociceptin (Noc; 300 nm) and then baclofen (Bacl; 10 μm) for PAG neurons in which nociceptin did (A) and did not (B) inhibit synaptic transmission. IPSCs were evoked every 30 sec. C, D, Averaged traces (n = 4) of evoked IPSCs before and then during application of nociceptin (Noc; 300 nm) and baclofen (Bacl; 10 μm) for the time plots of A and B, respectively.E, F, Histograms of the inhibition of the evoked IPSC produced by (E) nociceptin and (F) baclofen in all neurons. Neurons were clamped to a potential of −74 mV.