Fig. 2.

Within-session tolerance in animal M103 determined with the same microdialysis perfusion rate (5 μl/min) throughout, indicating the validity of the results for this animal in Figure 1. (Fig. 1, top left, shows data from studies with different flow rates for the first and second infusions.)Solidcircles represent the first injection; opencircles represent the second injection (n = 4 trials). Basal DA levels were as follows: first infusion, 1.42 ± 0.53 fmol/μl; second infusion, 1.78 ± 0.60 fmol/μl;t₍₆₎ = −0.45, NS.