The role of dopamine receptors in the modulation of nucleus accumbens noradrenaline release was investigated in superfused rat brain slices. At concentrations of </=1 microM, dopamine enhanced, whereas at higher concentrations dopamine inhibited electrically evoked [3H]noradrenaline release. The D1 receptor agonist SKF-38393 increased, whereas the D2 agonist quinpirole inhibited evoked [3H]nora...

Renal dopamine has been proposed to be involved in the regulation of glomerular filtration rate (GFR). Because inhibition of dopamine D2 receptors abolishes the renal hyperfiltration due to amino acid load, we tested the hypothesis that pharmacological activation of D2-like receptors mimicked this renal response. In anesthetized rats, quinpirole (0.3 microgram . 100 g-1 . min-1), an agonist for...

Agonists of dopamine receptors can lower blood pressure by vasodilation through action on dopamine1 receptors, inhibition of sympathetic nerve activity by action on dopamine2 receptors, or actions in the central nervous system. Fenoldopam, a selective dopamine1 agonist, piribedil, a selective dopamine2 agonist, and dipropyl dopamine, a mixed dopamine1 and dopamine2 agonist, were injected intrav...

Aripiprazole, a dopamine D(2) receptor partial agonist, is used to treat schizophrenia. Although aripiprazole has been reported to protect non-dopaminergic neurons, its effect on dopaminergic neurons has yet to be investigated. In the present study, we examined whether aripiprazole protected dopaminergic neurons against glutamate-induced cytotoxicity in rat mesencephalic cultures. Pretreatment ...

In mammalian retina, the rod bipolar cells synapse on the AII amacrine cells, which are therefore the third-order neurons in the rod-signal pathway. The AII amacrine cells are connected by gap junctions, both to each other and to fourth-order, On-center cone bipolar cells. They also receive synaptic input from the dopaminergic amacrine cells, and in this study, we investigated whether dopamine ...

The current study assessed the olfactory sensitivity of the goldfish (Carassius auratus L.) to the catecholamines, their immediate precursors and metabolites by use of the electro-olfactogram (EOG). The olfactory system of the goldfish was found to be sensitive to both adrenaline and dopamine with thresholds of detection of 10(-7.8) and 10(-7.9) M respectively, but less so to noradrenaline (thr...

Positron emission tomography and in vivo microdialysis were used to study serotonin's role in modulating striatal dopamine. Serial PET studies were performed in adult female baboons at baseline and following drug treatment, using the dopamine (D2) selective radiotracer, 11C-raclopride. The serotonergic system was manipulated by administration of the selective 5-HT reuptake inhibitor, citalopram...

Dopamine and dopamine-receptor function are often implicated in behavioral inhibition, and deficiencies within behavioral inhibition processes linked to attention deficit/hyperactivity disorder (ADHD), schizophrenia, obsessive-compulsive disorder, and drug addiction. In the stop-signal task, which measures the speed of the process of inhibition [stop-signal reaction time (SSRT)], psychostimulan...

Hedonic overconsumption contributing to obesity involves altered activation within the mesolimbic dopamine system. Dysregulation of dopamine signaling in the nucleus accumbens shell (NAS) has been implicated in reward-seeking behaviors, such as binge eating, which contributes to treatment resistance in obesity (Wise, 2012). Direct modulation of the NAS with deep brain stimulation (DBS), a surgi...

The cellular localization of DARPP-32, a dopamine- and cAMP-regulated phosphoprotein of Mr 32,000 that appears to mediate certain actions of dopamine in the mammalian brain by acting as an inhibitor of protein phosphatase 1, was studied in the kidney of several species. DARPP-32 mRNA and DARPP-32-like immunoreactivity were found in the cytoplasm of cells in the thick ascending limb of the loop ...