Drugs of abuse modulate the phosphorylation of ARPP-21, a cyclic AMP-regulated phosphoprotein enriched in the basal ganglia

Academic Article


  • ARPP-21 is a cyclic AMP-regulated phosphoprotein of M(r) 21 kDa that is enriched in the cell bodies and terminals of medium-sized spiny neurons in the basal ganglia. Using a new phosphorylation state-specific antibody selective for the detection of ARPP-21 phosphorylated on Ser55, we have demonstrated that activation of dopamine D1 receptors increased the level of ARPP-21 phosphorylation in mouse striatal slices. Conversely, activation of D2 receptors caused a large decrease in ARPP-21 phosphorylation. Treatment of mice with either methamphetamine or cocaine resulted in increased ARPP-21 phosphorylation in vivo. Studies using specific inhibitors of protein phosphatases and experiments in mice bearing a targeted deletion of the gene for DARPP-32, a dopamine-activated inhibitor of protein phosphatase-1, indicated that protein phosphatase-2A is primarily responsible for dephosphorylation of ARPP-21 in mouse striatum. These results demonstrate that phosphorylation and dephosphorylation of ARPP-21 are tightly regulated in the striatum. We speculate that ARPP-21 might mediate some of the physiologic effects of dopamine and certain drugs of abuse in the basal ganglia. Copyright (C) 2000 Elsevier Science Ltd.
  • Authors

    Published In

  • Neuropharmacology  Journal
  • Digital Object Identifier (doi)

    Author List

  • Caporaso GL; Bibb JA; Snyder GL; Valle C; Rakhilin S; Fienberg AA; Hemmings HC; Nairn AC; Greengard P
  • Start Page

  • 1637
  • End Page

  • 1644
  • Volume

  • 39
  • Issue

  • 9