Figure 4. Halothane depressed the native excitatory postsynaptic potential (EPSC) and its two components. (a) Native EPSCs recorded at -30 mV in 1 mM Magnesium2+. (b) Non-n-methyl-D-aspartate (non-NMDA) EPSCs recorded in another cell at -60 mV in Magnesium2+ -free saline containing 100 micro Meter aminophosphonovaleric acid (APV). (c) NMDA EPSCs recorded in another cell at -60 mV in Magnesium2+ -free saline containing 5 micro Meter 6-nitro-7-cyano-quinoxaline-2,3-dion (CNQX). In all three cases, exchanging to salines saturated with 0.9% halothane rapidly depressed the EPSCs. A steady state was achieved within 8-12 min. Reperfusion with control salines reversed the halothane depression within 8-15 min. Time calibrations in the three panels differ.