Figure 7.

Acute application of dopamine, but not isoproterenol, completely restores firing pattern in sucrose prepared slices. Experimental conditions as in Figure 5. APs were recorded in current clamp in the absence/presence of dopamine (DA) or isoproterenol (ISO). (A) After 6–10 min application of DA (20 μM), or 10 μM ISO the AP frequency of neurons in sucrose prepared slices was either completely (DA) or partially (ISO) decreased, back to levels observed in ACSF prepared slices (*p < 0.05). Typical original traces are shown as insets. (B) Representative original traces for rise times and latency changes in response to 120 pA current injection. First and last interspike intervals were prolonged after acute application of DA (but not ISO) to a comparable level as observed in ACSF prepared slices [(C,D), *p < 0.05]. The prolonged rise times typical for neurons after sucrose preparation were reduced by acute application of DA or ISO [(E), **p < 0.01]. (F) The first AP was generated significantly later after application of DA compared to sucrose preparation. ISO had no effect on spike latency. All measurements were performed with APs induced by 120 pA current injection (*p < 0.05, multiple comparisons were performed by ANOVA).