Figure 7.

The number of action potentials elicited by positive current steps is reduced by dopamine. (a) Traces show action potentials generated in response to 500 milliseconds duration, 60 pA current steps before and after application of 50 μM dopamine. The example shown reflects a particularly large reduction to only one action potential following application of dopamine. Action potentials are truncated. (b) Group data show a reduction in firing for both the 10 and 50 μM conditions but only the reduction in the 10 μM condition was significant.