| Figure 1. |
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| Illustration of the effects of the local application of DA on both IA and IK observed in DA neurons maintained in primary culture. The whole-cell current traces were obtained from cells under control conditions (CONTROL), after the pretreatment with pertussis toxin (PERTUSSIS TOXIN), and after the intracellular application of a polyclonal antibody selective for the a subunit of Go (Goa ANTIBODY). It can be seen that under control conditions the application of DA (100 mM in the pressure ejection pipette) readily increased the magnitude of IA and IK. In contrast, the other two treatments completely blocked these responses to DA autoreceptor stimulation. Both currents were measured under whole-cell patch recording conditions. To measure IA, the membrane was held at -40 mV and then stepped to -90 mV for 200 msec before jumping to the test membrane potential of 30 mV. To measure IK, the membrane was held at -60 mV and jumped to a test potential of 30 mV. (See ref. 42 for complete discussion.) |
published 2000