Figure 7.
Normal DA transporter and DA receptor number and function in α6L9′S and α4KO/α6L9′S mice. A–C, Normal DA-related pharmacological parameters in α6L9′S and α4KO/α6L9′S mice as determined by DAT and DA receptor ligand binding. Brain regions (OT and ST) from WT, α6L9′S, α4KO, and α4KO/α6L9′S mice were dissected and labeled with the indicated ligand followed by washout and quantification by scintillation counting. Raw binding values are indicated as fmol/mg protein for mazindol (DAT ligand), SCH23390 (D1 receptor ligand), and raclopride (D2 receptor ligand). D, E, Normal DA transporter function in α6L9′S and α4KO/α6L9′S mice. Synaptosomes were prepared as in Figure 2, but [3H]dopamine uptake was assayed at 50 nm (D) or 1 μm (E) [DA]o for all genotypes. F, Ratio of DAT activity at 1 μm (“high”) versus 50 nm (“low”) [DA]o. Data are ratios of the values in D and E. Data are expressed as mean ± SEM. The number of mice in each group was as follows: n = 9; α6L9′S, n = 9; α4KO, n = 8; α4KO/α6L9′S, n = 8. All statistically significant comparisons are indicated. *p < 0.05.