Fig. 1. Isoflurane inhibits the excitatory postsynaptic current (EPSC) dose dependently. (A ) Isoflurane at 0.35 and 1.05 mm (bars ) inhibited the EPSC to different levels. The EPSC was measured every 20 s. (B ) Sampled EPSCs (a , b , and c ) taken at times indicated in A . Stimulation artifacts are truncated. (C ) The percent inhibition of the EPSC amplitude plotted versus isoflurane concentration in the slice chamber from eight synapses. With the use of the Igor program (