Fig. 7. Xenon affected neither the mean amplitudes nor the mean frequency of miniature inhibitory postsynaptic currents (IPSCs) in the spinal lamina IX neurons. Continuous chart recording of miniature IPSCs at 0 mV in the presence of Tetrodotoxin (TTX) (1 μM) during the action of xenon (upper trace ) (A ). Five consecutive traces of miniature IPSCs are shown on an expanded time scale (lower traces ). Cumulative distributions of the amplitude (left ) and interevent interval (right ) of miniature IPSCs before (continuous line ) and during (dotted line ) the action of xenon. Xenon had little effect on the distributions both of the amplitude and interevent interval, as determined using the Kolmogorov-Smirnov test (B ). HP = holding potential.