Figure 3. Paired-pulse facilitation is not affected by atracurium. (A) Graph showing the changes in slope of the first (a,b) and second EPSPs (c,d) evoked by orthodromic paired activation of a group of Schaffer collaterals at 50-ms intervals. Data are expressed as percent of baseline values for the first EPSP. They are mean +/- SEM of five experiments. Inset traces are representative field potentials recorded before (a,c) and during (b,d) atracurium application. (B) Ratio of facilitation (calculated as the ratio of slopes of the second over the first EPSP).