Figure 2.

In vitro effects of cocaine on synaptosomes from wild-type (wt) and Go2α^−/− mice. A) Synaptosomes from wt or Go2α^−/− mouse brains were loaded with [³H]dopamine for 10 min at 37°C, either in the absence or presence of 5 μM cocaine. Nonspecific uptake using 20 μM GBR 12909, a specific inhibitor of DAT, was subtracted. As expected, cocaine completely blocked uptake into synaptosomes with no difference between the genotypes. *P < 0.05. B) Synaptosomes from both wild-type and Go2α^−/− mice were permeabilized by SLO, and vesicular uptake was determined in the absence or presence of 5 μM cocaine. Nonspecific uptake in the presence of reserpine was subtracted. Vesicular uptake was not affected by cocaine, and there was no difference between the genotypes. Data represent means ± sd of 3 determinations.