Fig. 3.
The D2R regulates phosphatase activity. A: mouse RPTCs were treated with vehicle or with the PP2A inhibitor okadaic acid (2 nM). Phosphatase activity was assayed using a fluorogenic substrate as described in materials and methods. Protein expression of Akt, p-Akt, GSK3β, and p-GSK3β was quantified by immunoblotting. Inset: 1 set of immunnoblots. Results are expressed as percentage of vehicle. *P < 0.05 vs. vehicle; n = 5/group. B: mouse RPTCs transfected with NS siRNA or D2R siRNA were treated with quinpirole (1 μM) or vehicle for the indicated time periods. Phosphatase activity was determined as above. Results are expressed as percentage of NS siRNA at time 0. *P < 0.05 vs. basal 0; n = 4/group.