Fig. 4. F6 affects inhibitory postsynaptic current (IPSC) amplitude indirectly. (  A ) A time series plot of averaged normalized IPSC amplitudes and 10–90% rise times from three experiments. Upon perfusion with F6 containing solution, the IPSC rise time increased and there was a concomitant decrease in amplitude. (  B ) IPSC amplitudes varied with changes in rise time. Normalized IPSC amplitudes are plotted against normalized rise times, data from the cells shown in (  A ). Note the linear correlation of the two parameters (correlation coefficient =0.84). For these cells, the concentration of F6 had reached 30–40 μm after 15 min of application.