查看文章

Mice with a genetic disruption of the dopamine transporter (DAT^–/–) exhibit locomotor hyperactivity and profound alterations in the homeostasis of the nigrostriatal system, e.g. a dramatic increase in the extracellular dopamine level. Here, we investigated the adaptive changes in dopamine D1, D2 and D3 receptor gene expression in the caudate putamen and nucleus accumbens of DAT^–/– mice. We used quantitative in situ hybridization and found that the constitutive hyperdopaminergia results in opposite regulations in the gene expression for the dopamine receptors. In DAT^–/– mice, we observed increased mRNA levels encoding the D3 receptor (caudate putamen, +60–85%; nucleus accumbens, +40–107%), and decreased mRNA levels for both D1 (caudate putamen, −34%; nucleus accumbens, −45%) and D2 receptors (caudate putamen, −36%; nucleus accumbens, −33%). Furthermore, we assessed the …