Figure 7.
GNa-dependent effects on EPSPs are exerted at the single-neuron level. A, When QX-314 (5 mm) was included in the postsynaptic recording pipette, the EPSP was not affected by TTX (500 nm). B, C, Summary data illustrating that TTX did not affect EPSP amplitude (B; n = 5) or AII VM (C; n = 12) in the presence of internal QX-314. D, TTX effects on AII amacrines are abolished when QX-314 is present in the recording pipette: a slow current ramp from −75 to +75 pA in 2 s (top) induced voltage changes in an AII loaded with QX-314. For comparison, note Figure 1, D and E. E, As in Figure 3C, fluctuations in membrane potential, isolated by subtracting a smoothed curve from the trace illustrated, are plotted against VM (VREST of −50 mV).