Figure 3
Homosynaptic postburst depression is associated with a decreased pool of primed vesicles. A, One experiment illustrating the effect of a 3-impulse, 50 Hz, conditioning on a 10-impulse, 50 Hz, test stimuli ("3+10"), calibration bar 100 ms, 50 pA. B, One experiment illustrating the effect of a 10-impulse, 50 Hz, conditioning on a 10-impulse, 50 Hz, test stimuli ("10+10"), calibration bar 100 ms, 50 pA. C, The amount of depression as a function of stimulus number in the 10-impulse, 50 Hz, test train following 3-impulse (grey line) and 10-impulse (black line) conditioning. D, Cumulative EPSC magnitude as a function of stimulus number in a 10-impulse, 50 Hz, train. The cumulative responses during a control train (black) is compared to the cumulative responses during a train evoked 500 ms after a 3-impulse, 50 Hz, conditioning burst (red). EPSCs were normalized with respect to the magnitude of the 1st EPSC in the control train. A linear fit was applied to the last four data points in the cumulative train response and that line was extrapolated to the first stimulus (dashed lines). E, Cumulative EPSC magnitude as a function of stimulus number in 10-impulse, 50 Hz, train. The responses during a control train (black) is compared to the responses during a train evoked 500 ms after a 10-impulse, 50 Hz, conditioning train (red). EPSCs were normalized with respect to the magnitude of the 1st EPSC in the control train. A linear fit was applied as above (dashed lines).