Fig. 1. In acute slice preparations of the prefrontal cortex (PFC) and substantia gelatinosa (SG), xenon reversibly reduces compound synaptic transmission but has no effect on γ-aminobutyric acid type A (GABA^A) receptor–mediated inhibitory synaptic transmission. (  A and  B ) Compound postsynaptic currents, evoked upon electrical stimulation (ePSCs), were recorded from 5 (6) neurons in the PFC (SG). Application of 1.9 mm xenon diminished the ePSC amplitudes to 70.1 ± 10.3% (74.3 ± 4.2%) of control responses. Upon termination of xenon application, the ePSCs nearly recovered to control level. (  C and  D ) GABA^Areceptor–mediated inhibitory postsynaptic currents evoked upon electrical stimulation (GABA^A-eIPSCs) were isolated using specific receptor antagonists and recorded at a holding potential of −50 mV. Xenon, 1.9 mm, did not affect amplitudes of GABA^A-eIPSCs in the PFC (  C ; n = 5) or in the SG (  D ; n = 4). Each  data point represents either mean ePSC or GABA^A-eIPSC amplitude ± SEM normalized to the respective control values (5 min before start of xenon application, which is indicated by the  black bars ).  Insets show representative current traces. § Stimulation artifact.