Figure 6.

Dopamine does not modulate frequency-dependent depression of backpropagating APs. A, Trains of antidromic APs (10, 20, 50, and 100 Hz) recorded in the apical dendrite (250 μm from the soma) before (black) and during (gray; offset) bath application of 10 μm dopamine. B, Plot of AP amplitude versus timing for the four trains shown in A. C, Ratio of the amplitude of the tenth versus first AP during 50 Hz trains as a function of distance from the soma in control (black) and dopamine (gray) conditions.