We have analyzed the role of N-linked glycosylation in functional cell surface expression of the D1 and D5 dopamine receptor subtypes. Treatment of transfected HEK 293 cells with tunicamycin, an inhibitor of N-linked oligosaccharide addition, was found to prevent localization of D5 receptors in the plasma membrane. In contrast, tunicamycin treatment had no effect on the plasma membrane localiza...

Dopaminergic signaling within the basal ganglia has classically been thought to occur within two distinct neuronal pathways; the direct striatonigral pathway which contains the dopamine D1 receptor and the neuropeptides dynorphin (DYN) and substance P, and the indirect striatopallidal pathway which expresses the dopamine D2 receptor and enkephalin (ENK). A number of studies have also shown, how...

The enzyme phosphodiesterase 10A (PDE10A) regulates the activity of striatal, medium spiny neurons (MSNs), which are divided into a behaviorally stimulating, Gs-coupled D1 receptor-expressing "direct" pathway and a behaviorally suppressant, Gi-coupled D2 receptor-expressing "indirect" pathway. Activating both pathways, PDE10A inhibitors (PDE10AIs) combine functional characteristics of D2 antago...

Impaired working memory is a common feature of neuropsychiatric disorders. It is dependent on control of the medial prefrontal cortex (mPFC) neurons by dopamine. The purpose of this study was to test the effects of a D1/5-type dopamine receptor agonist (SKF 38393, 10 microM) on the membrane potential and on voltage-dependent fast-inactivating Na+ currents in mPFC pyramidal neurons obtained from...

Interactions between the basal ganglia and the cerebral cortex are critical for normal goal-directed behavior. In the present study, we used immediate-early genes (c-fos, zif 268) as functional markers to investigated how basal ganglia output altered by stimulation/blockade of D1 dopamine receptors in the striatum affects cortical function. Systemic administration of the mixed D1/D2 receptor ag...

Dopamine receptors are abundant along the central nigrostriatal tract and expressed as 5 subtypes in two receptor families. In PD, compensatory changes dopamine emerge a consequence of loss nerve terminals or dopaminergic pharmacotherapy. We performed systematic review meta-analysis available PET single-photon emission computed tomography studies that have investigated PSP MSA. The inclusion cr...

The striatum is the main recipient of dopaminergic innervation. Striatal projection neurons are controlled by cholinergic and GABAergic interneurons. The effects of dopamine on projection neurons and cholinergic interneurons have been described. Its action on GABAergic interneurons, however, is still unknown. We studied the effects of dopamine on fast-spiking (FS) GABAergic interneurons in vitr...

GABA neurons in the substantia nigra pars reticulata receive input from GABAergic fibers originating in the forebrain. The role of dopaminergic D1 receptors located on these fibers was investigated using tight-seal whole-cell recordings from visually identified pars reticulata neurons of rat substantia nigra slices. Nondopaminergic pars reticulata neurons were characterized by their electrophys...

Dopamine receptors have been found to be of at least two types, and interest has focused on the possible differential role played by each in the control of behavior. The recent finding that SCH 23390 selectively blocks D1 receptors has provided a new tool. To examine the contribution of D1 receptors to locomotor activity and rearing, rats were injected SC with doses of 0.01, 0.1 and 1.0 mg/kg a...

The serine/threonine kinase Akt is a downstream target of dopamine receptor signaling that is inhibited/dephosphorylated in response to direct and indirect dopamine receptor agonists. Although pharmacological studies uncovered the involvement of D2-class dopamine receptors in Akt regulation, they did not identify the role of individual receptor subtypes in this process. Here we used knock-out m...