Figure 1.

AMPA receptors do not contribute to unitary postsynaptic currents evoked in CA3 principal cells by minimal stimulation of granule cells in the dentate gyrus. A, Unitary synaptic currents evoked in a CA3 pyramidal cell at P4 with different stimulation intensities before (Control) and during application of GYKI 52466 (30 μm). Each trace is the average of 15–20 responses (including failures). B, Peak amplitudes of synaptic currents represented in A are plotted as a function of stimulus intensities. The bars are SEM, and the dashed lines are the averaged amplitude of GPSCs. Latency (C) and rise time (D) distributions of individual currents evoked in a CA3 pyramidal cell by minimal stimulation of granule cells in the dentate gyrus in the absence (Control) and in the presence of GYKI 52466. Note that, in the presence of GYKI 52466, the unimodal distribution of latencies and rise times of individual responses did not change.