Introduction to Dopaminergic Receptors

Despite extensive knowledge on genetic variability of dopaminergic receptors (DR), few studies have addressed their relevance as possible influencers of clinical heterogeneity in PD patients.

Furthermore, the possible roles of adrenergic and dopaminergic receptors were also studied.

D1R antagonist SCH23390 and D2R antagonist sulpiride partially alleviated the aberrances of locomotion and heart rate, indicating dopaminergic receptors were involved in the bidirectional dosage-dependent pattern of NEP-induced performance.

Limited experimental studies have revealed that pharmacological agents of dopaminergic receptors can significantly modulate the electrically-induced long-term potentiation/depression (LTP/LTD) of the hippocampal Schaffer collateral CA1 pyramidal (SC-CA1) synapses, a cellular model of learning and memory, in a time and dose dependent manner.

Thus, the efficiency of D2‐like agonists may reflect the involvement of other dopaminergic receptors or normalisation of motor circuit abnormalities downstream from defects caused by MEIS1 dysfunction.

Tardive dyskinesia (TD) is a movement disorder that appears after chronic use of drugs that block dopaminergic receptors such as antipsychotics.

The identified compound 8 behaved as a potent α2A/5-HT7 receptor antagonist and displayed moderate-to-high selectivity over α1-adrenoceptor subtypes and selected serotonin and dopaminergic receptors.

Although previous studies have shown that modafinil-induced arousal depends on the dopaminergic receptors and transporters, the specific dopaminergic population underlying this mechanism remained unclear.

The cerebellum receives dopaminergic innervation and expresses the five types of described dopaminergic receptors.

Conclusion These findings suggest that the antidepressant-like activity exhibited by morin might be mediated via interactions with 5-HTergic, noradrenergic, and dopaminergic receptors, while the memory-enhancing effect might involve interaction with both 5-HTergic and cholinergic receptors.

After assessing the affinity for serotonergic and dopaminergic receptors, and serotonin transporter, we determined intrinsic activity of the compound at the 5-HT1A and D2 receptors.

OBJECTIVE To investigate the direct effect of D1-like dopaminergic receptors antagonist on Th17-cells function in multiple sclerosis (MS) in vitro.

For example, alterations in the expression of the dopaminergic receptors D1 and D2, reactive oxygen species (ROS) and the c-Fos protein in the cortex have been observed.

Decades of research have highlighted the importance of optimal stimulation of cortical dopaminergic receptors, particularly the D1R receptor (D1R), for prefrontal-mediated cognition.

That was partly explained by Brugger and colleagues [4], through different mechanisms, including enhanced neurodegeneration by peripheral inflammation, downregulation of dopaminergic receptors, altered transport of dopaminergic drugs through the blood–brain barrier, altered presynaptic reuptake of L-dopa and dopamine, respectively, and impaired packaging of neurotransmitters into vesicles, among other explanations.

Here, we examined the protein levels of dopaminergic receptors (D1R and D2R) in different phases of the experimental autoimmune encephalomyelitis (EAE) model.

The present study assessed the effects of blocking noradrenergic and dopaminergic receptors on nicotine and cocaine unconditioned and conditioned memory modulation.

OBJECTIVE: So, the aim of the current study was to determine anti-nociceptive activity of the testosterone and its interaction with opioidergic, GABAergic and dopaminergic receptors in sciatic nerve ligated male rat.

Recent studies show that by acting on the dopaminergic receptors, it is possible to modulate Th17-immune response, which play a crucial role in the pathogenesis of multiple sclerosis.

The reduction in calyx sodium current in response to dopamine suggests efferent signaling through D2 dopaminergic receptors may occur via common mechanisms to decrease excitability in inner ear afferents.

Also, the dentate gyrus (DG) of the hippocampus expresses various receptors, including dopaminergic receptors.

Acute activation of dopaminergic receptors failed to rescue the impaired intrinsic excitability of M1 PTNs in parkinsonian mice.

Some pharmacogenetic markers of therapy safety have been established: single nucleotide variants/polymorphisms of candidate genes for dopaminergic receptors D2 and D3 (DRD2 (rs1799732 (-141C Ins/Del)), DRD3 (rs6280 (Ser9Gly)), laforine phosphatase (EPM2A (rs1415744 (C/T)).

Therefore, we provide evidence that corroborates the idea that D1-like dopaminergic receptors, by activation of the PKA pathway, are involved in the effects of acute physical exercise on memory.

This locally-produced pancreatic DA signals via both α- and β-cell adrenergic and dopaminergic receptors with different affinities to regulate glucagon and insulin release.

In the cerebellum and cerebral cortex, expression of genes encoding cholinergic, adrenergic, and dopaminergic receptors decreased, whereas in the hippocampus only expression of serotoninergic receptors genes was downregulated.

CONCLUSIONS The findings suggest that the ACC has an important role in acute thermal pain perception and modulates the analgesia induced by nicotine plus morphine via dopaminergic receptors.

We now evaluate whether both the blunted counterregulatory response to hypoglycemia and hypoglycemia unawareness are mediated by repeated activation of brain dopaminergic receptors.

In this study, we delineate the human monoamine oxidase (hMAO) inhibitory potential of natural Diels–Alder type adducts, mulberrofuran G (1), kuwanon G (2), and albanol B (3), from Morus alba root bark to characterize their role in Parkinson’s disease (PD) and depression, focusing on their ability to modulate dopaminergic receptors (D1R, D2LR, D3R, and D4R).

The pathophysiology of the disorder is well known, it relates to iron depletion and dopaminergic receptors in the brain, and this has aided the development of effective treatment.

We found that β-adrenergic receptors and dopaminergic receptors, dopamine β-hydroxylase, ki67, Runx2, and serotonergic receptor gene expression were significantly higher in tumour tissue than in adjacent and non-oncological bone.

Pharmacotherapy tries to compensate for the deficit of dopaminergic signaling by inhibiting dopamine metabolism (MAO-B inhibitors), by substituting dopamine (levodopa) or by directly stimulating dopaminergic receptors with agonists (Zeuner et al.

Results show that CD8+ T cells express both D1-like and D2-like dopaminergic receptors (DR), tyrosine hydroxylase (TH), the rate-limiting enzyme in the synthesis of DA, and vesicular monoamine transporter (VMAT) 2 and contain high levels of intracellular DA.

Objective: Parkinson’s disease (PD) patients are usually treated with L-dopa and/or dopaminergic agonists, which act by binding five types of dopaminergic receptors (DRD1–DRD5).

Recent studies have shown that dopamine can enhance or inhibit the functions of innate and adaptive immune system, depending on the activation of different dopaminergic receptors, and can therefore influence the course of experimental autoimmune encephalomyelitis (EAE) and MS.

These effects of Bj-PRO-7a seem to be dependent on M1R activation and dopaminergic receptors and rely on catecholaminergic pathways.

We hypothesized that repeated activation of dopaminergic receptors by agonists could lead to neuronal cell death.

Moreover, dopaminergic receptors (DR) are expressed on immune cells.

Because of its selective binding to dopaminergic receptors, side‐effects of amisulpride are rare.

Dopaminergic receptors from the renal vasculature are also stimulated by dopamine which leads to dilation of renal blood vessels and increases glomerular filtration rate, renal blood flow, sodium excretion, and urine outputGenerally, dopamine receptors are activated by low doses of dopamine (0.

However, the precise role of dopaminergic receptors in the BLA and the CeA during reward-related behaviors remains to be determined.

In this study the effects of apelin-13 were investigated on motor disorders and striatal synaptosomal expression of PSD-95, neurexin1, neuroligin, metabotropic glutamate receptor (mGlu R1) and dopaminergic receptors (DR1 and DR2) in rat parkinsonism experimental model.

CONCLUSION With the expansion of pharmacotherapy in psychotic conditions, depression and endocrine abnormalities along with a sharp increase in prevalence of type two diabetes and disturbances of glucose homeostasis as a major risk factor for many cardiovascular complications and associated mortalities; it seems a critical analysis of recent investigations on drugs which act as agonists or antagonists of dopaminergic receptors in various tissues and organs may provide better insight into how safe and efficient these medicines could be prescribed.

We therefore sought to investigate the contribution of DMS dopaminergic receptors in the regulation of cue‐elicited and innate approach‐avoidance decision‐making.

Antipsychotic drugs, known as the antagonists of dopaminergic receptors, may also affect a large spectrum of other molecular signaling pathways in the brain.

Key Points DBS of the PrL was able to disrupt consolidation of fear memories We observed demonstrated short-term changes in dopaminergic receptors, c-Fos expression, and various neurotransmitters and their metabolites in the vHPC We established a partial causal role of dopapmine 2 receptors in the effects.

Results showed that after long‐term sugar exposure, mPFC activation of &bgr;‐adrenergic receptors with clenbuterol delayed aversive memory extinction, but the blockade with propranolol or activation of dopaminergic receptors with apomorphine increased CTA latent inhibition and accelerated aversive memory extinction only after acute sugar exposure.

CONCLUSIONS Results showed that MS had antidepressant activity possibly mediated through α1-adrenergic and D2 dopaminergic receptors, without significant anxiolytic effect.