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Channer B, Matt SM, Nickoloff-Bybel EA, Pappa V, Agarwal Y, Wickman J, Gaskill PJ. Dopamine, Immunity, and Disease. Pharmacol Rev 2023; 75:62-158. [PMID: 36757901 PMCID: PMC9832385 DOI: 10.1124/pharmrev.122.000618] [Citation(s) in RCA: 75] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 08/02/2022] [Accepted: 08/04/2022] [Indexed: 12/14/2022] Open
Abstract
The neurotransmitter dopamine is a key factor in central nervous system (CNS) function, regulating many processes including reward, movement, and cognition. Dopamine also regulates critical functions in peripheral organs, such as blood pressure, renal activity, and intestinal motility. Beyond these functions, a growing body of evidence indicates that dopamine is an important immunoregulatory factor. Most types of immune cells express dopamine receptors and other dopaminergic proteins, and many immune cells take up, produce, store, and/or release dopamine, suggesting that dopaminergic immunomodulation is important for immune function. Targeting these pathways could be a promising avenue for the treatment of inflammation and disease, but despite increasing research in this area, data on the specific effects of dopamine on many immune cells and disease processes remain inconsistent and poorly understood. Therefore, this review integrates the current knowledge of the role of dopamine in immune cell function and inflammatory signaling across systems. We also discuss the current understanding of dopaminergic regulation of immune signaling in the CNS and peripheral tissues, highlighting the role of dopaminergic immunomodulation in diseases such as Parkinson's disease, several neuropsychiatric conditions, neurologic human immunodeficiency virus, inflammatory bowel disease, rheumatoid arthritis, and others. Careful consideration is given to the influence of experimental design on results, and we note a number of areas in need of further research. Overall, this review integrates our knowledge of dopaminergic immunology at the cellular, tissue, and disease level and prompts the development of therapeutics and strategies targeted toward ameliorating disease through dopaminergic regulation of immunity. SIGNIFICANCE STATEMENT: Canonically, dopamine is recognized as a neurotransmitter involved in the regulation of movement, cognition, and reward. However, dopamine also acts as an immune modulator in the central nervous system and periphery. This review comprehensively assesses the current knowledge of dopaminergic immunomodulation and the role of dopamine in disease pathogenesis at the cellular and tissue level. This will provide broad access to this information across fields, identify areas in need of further investigation, and drive the development of dopaminergic therapeutic strategies.
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Affiliation(s)
- Breana Channer
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (B.C., S.M.M., E.A.N-B., Y.A., J.W., P.J.G.); and The Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania (V.P.)
| | - Stephanie M Matt
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (B.C., S.M.M., E.A.N-B., Y.A., J.W., P.J.G.); and The Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania (V.P.)
| | - Emily A Nickoloff-Bybel
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (B.C., S.M.M., E.A.N-B., Y.A., J.W., P.J.G.); and The Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania (V.P.)
| | - Vasiliki Pappa
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (B.C., S.M.M., E.A.N-B., Y.A., J.W., P.J.G.); and The Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania (V.P.)
| | - Yash Agarwal
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (B.C., S.M.M., E.A.N-B., Y.A., J.W., P.J.G.); and The Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania (V.P.)
| | - Jason Wickman
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (B.C., S.M.M., E.A.N-B., Y.A., J.W., P.J.G.); and The Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania (V.P.)
| | - Peter J Gaskill
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania (B.C., S.M.M., E.A.N-B., Y.A., J.W., P.J.G.); and The Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania (V.P.)
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Interactions between the intrarenal dopaminergic and the renin-angiotensin systems in the control of systemic arterial pressure. Clin Sci (Lond) 2022; 136:1205-1227. [PMID: 35979889 DOI: 10.1042/cs20220338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 07/31/2022] [Accepted: 08/03/2022] [Indexed: 11/17/2022]
Abstract
Systemic arterial hypertension is one of the leading causes of morbidity and mortality in the general population, being a risk factor for many cardiovascular diseases. Although its pathogenesis is complex and still poorly understood, some systems appear to play major roles in its development. This review aims to update the current knowledge on the interaction of the intrarenal renin-angiotensin system (RAS) and dopaminergic system in the development of hypertension, focusing on recent scientific hallmarks in the field. The intrarenal RAS, composed of several peptides and receptors, has a critical role in the regulation of blood pressure (BP) and, consequently, the development of hypertension. The RAS is divided into two main intercommunicating axes: the classical axis, composed of angiotensin-converting enzyme, angiotensin II, and angiotensin type 1 receptor, and the ACE2/angiotensin-(1-7)/Mas axis, which appears to modulate the effects of the classical axis. Dopamine and its receptors are also increasingly showing an important role in the pathogenesis of hypertension, as abnormalities in the intrarenal dopaminergic system impair the regulation of renal sodium transport, regardless of the affected dopamine receptor subtype. There are five dopamine receptors, which are divided into two major subtypes: the D1-like (D1R and D5R) and D2-like (D2R, D3R, and D4R) receptors. Mice deficient in any of the five dopamine receptor subtypes have increased BP. Intrarenal RAS and the dopaminergic system have complex interactions. The balance between both systems is essential to regulate the BP homeostasis, as alterations in the control of both can lead to hypertension.
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Sokoloff P, Le Foll B. A Historical Perspective on the Dopamine D3 Receptor. Curr Top Behav Neurosci 2022; 60:1-28. [PMID: 35467293 DOI: 10.1007/7854_2022_315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Before 1990, the multiplicity of dopamine receptors beyond D1 and D2 had remained a controversial concept, despite its substantial clinical implications, at a time when it was widely accepted that dopamine interacted with only two receptor subtypes, termed D1 and D2, differing one from the other by their pharmacological specificity and opposite effects on adenylyl cyclase. It was also generally admitted that the therapeutic efficacy of antipsychotics resulted from blockade of D2 receptors. Thanks to molecular biology techniques, the D3 receptor could be characterized as a distinct molecular entity having a restricted anatomical gene expression and different signaling, which could imply peculiar functions in controlling cognitive and emotional behaviors. Due to the structural similarities of D2 and D3 receptors, the search for D3-selective compounds proved to be difficult, but nevertheless led to the identification of fairly potent and in vitro and in vivo selective compounds. The latter permitted to confirm a role of D3 receptors in motor functions, addiction, cognition, and schizophrenia, which paved the way for the development of new drugs for the treatment of psychiatric disorders.
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Affiliation(s)
| | - Bernard Le Foll
- Translational Addiction Research Laboratory, Centre for Addiction and Mental Health, Toronto, ON, Canada. .,Campbell Family Mental Health Research Institute, CAMH, Toronto, ON, Canada. .,Department of Psychiatry, Faculty of Medicine, University of Toronto, Toronto, ON, Canada. .,Departments of Family and Community Medicine, University of Toronto, Toronto, ON, Canada. .,Institute of Medical Science, University of Toronto, Toronto, ON, Canada. .,Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada. .,Waypoint Research Institute, Waypoint Centre for Mental Health Care, 5, Penetanguishene, ON, Canada.
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Dopamine Receptors and the Kidney: An Overview of Health- and Pharmacological-Targeted Implications. Biomolecules 2021; 11:biom11020254. [PMID: 33578816 PMCID: PMC7916607 DOI: 10.3390/biom11020254] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 02/05/2021] [Accepted: 02/06/2021] [Indexed: 12/21/2022] Open
Abstract
The dopaminergic system can adapt to the different physiological or pathological situations to which the kidneys are subjected throughout life, maintaining homeostasis of natriuresis, extracellular volume, and blood pressure levels. The role of renal dopamine receptor dysfunction is clearly established in the pathogenesis of essential hypertension. Its associations with other pathological states such as insulin resistance and redox balance have also been associated with dysfunction of the dopaminergic system. The different dopamine receptors (D1-D5) show a protective effect against hypertension and kidney disorders. It is essential to take into account the various interactions of the dopaminergic system with other elements, such as adrenergic receptors. The approach to therapeutic strategies for essential hypertension must go through the blocking of those elements that lead to renal vasoconstriction or the restoration of the normal functioning of dopamine receptors. D1-like receptors are fundamental in this role, and new therapeutic efforts should be directed to the restoration of their functioning in many patients. More studies will be needed to allow the development of drugs that can be targeted to renal dopamine receptors in the treatment of hypertension.
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Tutunea-Fatan E, Lee JC, Denker BM, Gunaratnam L. Heterotrimeric Gα 12/13 proteins in kidney injury and disease. Am J Physiol Renal Physiol 2020; 318:F660-F672. [PMID: 31984793 DOI: 10.1152/ajprenal.00453.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Gα12 and Gα13 are ubiquitous members of the heterotrimeric guanine nucleotide-binding protein (G protein) family that play central and integrative roles in the regulation of signal transduction cascades within various cell types in the kidney. Gα12/Gα13 proteins enable the kidney to adapt to an ever-changing environment by transducing stimuli from cell surface receptors and accessory proteins to effector systems. Therefore, perturbations in Gα12/Gα13 levels or their activity can contribute to the pathogenesis of various renal diseases, including renal cancer. This review will highlight and discuss the complex and expanding roles of Gα12/Gα13 proteins on distinct renal pathologies, with emphasis on more recently reported findings. Deciphering how the different Gα12/Gα13 interaction networks participate in the onset and development of renal diseases may lead to the discovery of new therapeutic strategies.
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Affiliation(s)
- Elena Tutunea-Fatan
- Matthew Mailing Centre for Translational Transplant Studies, Lawson Health Research Institute, London, Ontario, Canada
| | - Jasper C Lee
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Bradley M Denker
- Beth Israel Deaconess Medical Center and Department of Medicine, Harvard Medical School, Boston, Massachusetts
| | - Lakshman Gunaratnam
- Matthew Mailing Centre for Translational Transplant Studies, Lawson Health Research Institute, London, Ontario, Canada.,Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada.,Division of Nephrology, Department of Medicine, University of Western Ontario, London, Ontario, Canada
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Jordan CJ, Humburg BA, Thorndike EB, Shaik AB, Xi ZX, Baumann MH, Newman AH, Schindler CW. Newly Developed Dopamine D 3 Receptor Antagonists, R-VK4-40 and R-VK4-116, Do Not Potentiate Cardiovascular Effects of Cocaine or Oxycodone in Rats. J Pharmacol Exp Ther 2019; 371:602-614. [PMID: 31562201 PMCID: PMC6863462 DOI: 10.1124/jpet.119.259390] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 09/23/2019] [Indexed: 12/24/2022] Open
Abstract
Opioid and cocaine abuse are major public health burdens. Existing medications for opioid use disorder are limited by abuse liability and side effects, whereas no treatments are currently approved in the United States for cocaine use disorder. Dopamine D3 receptor (D3R) antagonists have shown promise in attenuating opioid and cocaine reward and mitigating relapse in preclinical models. However, translation of D3R antagonists to the clinic has been hampered by reports that the D3R antagonists GSK598,809 (5-(5-((3-((1S,5R)-1-(2-fluoro-4-(trifluoromethyl)phenyl)-3-azabicyclo[3.1.0]hexan-3-yl)propyl)thio)-4-methyl-4H-1,2,4-triazol-3-yl)-4-methyloxazole) and SB-277,011A (2-(2-((1r,4r)-4-(2-oxo-2-(quinolin-4-yl)ethyl)cyclohexyl)ethyl)-1,2,3,4-tetrahydroisoquinoline-6-carbonitrile) have adverse cardiovascular effects in the presence of cocaine. Recently, we developed two structurally novel D3R antagonists, R-VK4-40 and R-VK4-116, which are highly selective for D3R and display translational potential for treatment of opioid use disorder. Here, we tested whether R-VK4-40 ((R)-N-(4-(4-(2-Chloro-3-ethylphenyl)piperazin-1-yl)-3-hydroxybutyl)-1H-indole-2-carboxamide) and R-VK4-116 ((R)-N-(4-(4-(3-Chloro-5-ethyl-2-methoxyphenyl)piperazin-1-yl)-3-hydroxybutyl)-1H-indole-2-carboxamide) have unwanted cardiovascular effects in the presence of oxycodone, a prescription opioid, or cocaine in freely moving rats fitted with surgically implanted telemetry transmitters. We also examined cardiovascular effects of the D3R antagonist, SB-277,011A, and L-741,626 (1-((1H-indol-3-yl)methyl)-4-(4-chlorophenyl)piperidin-4-ol), a dopamine D2 receptor-selective antagonist, for comparison. Consistent with prior reports, SB-277,011A increased blood pressure, heart rate, and locomotor activity alone and in the presence of cocaine. L-741,626 increased blood pressure and heart rate. In contrast, R-VK4-40 alone dose-dependently reduced blood pressure and heart rate and attenuated oxycodone-induced increases in blood pressure and oxycodone or cocaine-induced increases in heart rate. Similarly, R-VK4-116 alone dose-dependently reduced cocaine-induced increases in blood pressure and heart rate. These results highlight the safety of new D3R antagonists and support the continued development of R-VK4-40 and R-VK4-116 for the treatment of opioid and cocaine use disorders. SIGNIFICANCE STATEMENT: Opioid and cocaine abuse are major public health challenges and new treatments that do not adversely impact the cardiovascular system are needed. Here, we show that two structurally novel dopamine D3 receptor antagonists, R-VK4-40 and R-VK4-116, do not potentiate, and may even protect against, oxycodone- or cocaine-induced changes in blood pressure and heart rate, supporting their further development for the treatment of opioid and/or cocaine use disorders.
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Affiliation(s)
- Chloe J Jordan
- Molecular Targets and Medications Discovery Branch (C.J.J., B.A.H., A.B.S., Z.-X.X., A.H.N.), Designer Drug Research Unit (M.H.B., C.W.S.), and Preclinical Pharmacology Section (E.B.T., C.W.S.), Intramural Research Program, National Institute on Drug Abuse, Baltimore, Maryland
| | - Bree A Humburg
- Molecular Targets and Medications Discovery Branch (C.J.J., B.A.H., A.B.S., Z.-X.X., A.H.N.), Designer Drug Research Unit (M.H.B., C.W.S.), and Preclinical Pharmacology Section (E.B.T., C.W.S.), Intramural Research Program, National Institute on Drug Abuse, Baltimore, Maryland
| | - Eric B Thorndike
- Molecular Targets and Medications Discovery Branch (C.J.J., B.A.H., A.B.S., Z.-X.X., A.H.N.), Designer Drug Research Unit (M.H.B., C.W.S.), and Preclinical Pharmacology Section (E.B.T., C.W.S.), Intramural Research Program, National Institute on Drug Abuse, Baltimore, Maryland
| | - Anver Basha Shaik
- Molecular Targets and Medications Discovery Branch (C.J.J., B.A.H., A.B.S., Z.-X.X., A.H.N.), Designer Drug Research Unit (M.H.B., C.W.S.), and Preclinical Pharmacology Section (E.B.T., C.W.S.), Intramural Research Program, National Institute on Drug Abuse, Baltimore, Maryland
| | - Zheng-Xiong Xi
- Molecular Targets and Medications Discovery Branch (C.J.J., B.A.H., A.B.S., Z.-X.X., A.H.N.), Designer Drug Research Unit (M.H.B., C.W.S.), and Preclinical Pharmacology Section (E.B.T., C.W.S.), Intramural Research Program, National Institute on Drug Abuse, Baltimore, Maryland
| | - Michael H Baumann
- Molecular Targets and Medications Discovery Branch (C.J.J., B.A.H., A.B.S., Z.-X.X., A.H.N.), Designer Drug Research Unit (M.H.B., C.W.S.), and Preclinical Pharmacology Section (E.B.T., C.W.S.), Intramural Research Program, National Institute on Drug Abuse, Baltimore, Maryland
| | - Amy Hauck Newman
- Molecular Targets and Medications Discovery Branch (C.J.J., B.A.H., A.B.S., Z.-X.X., A.H.N.), Designer Drug Research Unit (M.H.B., C.W.S.), and Preclinical Pharmacology Section (E.B.T., C.W.S.), Intramural Research Program, National Institute on Drug Abuse, Baltimore, Maryland
| | - Charles W Schindler
- Molecular Targets and Medications Discovery Branch (C.J.J., B.A.H., A.B.S., Z.-X.X., A.H.N.), Designer Drug Research Unit (M.H.B., C.W.S.), and Preclinical Pharmacology Section (E.B.T., C.W.S.), Intramural Research Program, National Institute on Drug Abuse, Baltimore, Maryland
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NHA2 is expressed in distal nephron and regulated by dietary sodium. J Physiol Biochem 2016; 73:199-205. [PMID: 27909897 DOI: 10.1007/s13105-016-0539-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 11/22/2016] [Indexed: 01/02/2023]
Abstract
Increased renal reabsorption of sodium is a significant risk factor in hypertension. An established clinical marker for essential hypertension is elevated sodium lithium countertransport (SLC) activity. NHA2 is a newly identified Na+(Li+)/H+ antiporter with potential genetic links to hypertension, which has been shown to mediate SLC activity and H+-coupled Na+(Li+) efflux in kidney-derived MDCK cells. To evaluate a putative role in sodium homeostasis, we determined the effect of dietary salt on NHA2. In murine kidney sections, NHA2 localized apically to distal convoluted (both DCT1 and 2) and connecting tubules, partially overlapping in distribution with V-ATPase, AQP2, and NCC1 transporters. Mice fed a diet high in sodium chloride showed elevated transcripts and expression of NHA2 protein. We propose a model in which NHA2 plays a dual role in salt reabsorption or secretion, depending on the coupling ion (sodium or protons). The identified novel regulation of Na+/H+ antiporter in the kidney suggests new roles in salt homeostasis and disease.
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Abstract
PURPOSE OF REVIEW The kidney mediates the excretion or conservation of water and electrolytes in the face of changing fluid and salt intake and losses. To ultrafilter and reabsorb the exact quantities of free water and salts to maintain euvolemia a range of endocrine, paracrine, and hormonal signaling systems have evolved linking the tubules, capillaries, glomeruli, arterioles, and other intrinsic cells of the kidney. Our understanding of these systems remains incomplete. RECENT FINDINGS Recent work has provided new insights into the workings of the communication pathways between tubular segments and the glomeruli and vasculature, with novel therapeutic agents in development. Particular progress has also been made in the visualization of tubuloglomerular feedback. SUMMARY The review summarizes our current understanding of pathway functions in health and disease, as well as future therapeutic options to protect the healthy and injured kidney.
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Affiliation(s)
- David A. Ferenbach
- Department of Medicine, Renal Division and Biomedical Engineering Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Centre for Inflammation Research, Queen’s Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Joseph V. Bonventre
- Department of Medicine, Renal Division and Biomedical Engineering Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Harvard-Massachusetts Institute of Technology, Division of Health Sciences and Technology, Cambridge, Massachusetts, USA
- Harvard Stem Cell Institute, Cambridge, Massachusetts, USA
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Renal dopamine receptors, oxidative stress, and hypertension. Int J Mol Sci 2013; 14:17553-72. [PMID: 23985827 PMCID: PMC3794741 DOI: 10.3390/ijms140917553] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 08/09/2013] [Accepted: 08/12/2013] [Indexed: 12/22/2022] Open
Abstract
Dopamine, which is synthesized in the kidney, independent of renal nerves, plays an important role in the regulation of fluid and electrolyte balance and systemic blood pressure. Lack of any of the five dopamine receptor subtypes (D1R, D2R, D3R, D4R, and D5R) results in hypertension. D1R, D2R, and D5R have been reported to be important in the maintenance of a normal redox balance. In the kidney, the antioxidant effects of these receptors are caused by direct and indirect inhibition of pro-oxidant enzymes, specifically, nicotinamide adenine dinucleotide phosphate, reduced form (NADPH) oxidase, and stimulation of anti-oxidant enzymes, which can also indirectly inhibit NADPH oxidase activity. Thus, stimulation of the D2R increases the expression of endogenous anti-oxidants, such as Parkinson protein 7 (PARK7 or DJ-1), paraoxonase 2 (PON2), and heme oxygenase 2 (HO-2), all of which can inhibit NADPH oxidase activity. The D5R decreases NADPH oxidase activity, via the inhibition of phospholipase D2, and increases the expression of HO-1, another antioxidant. D1R inhibits NADPH oxidase activity via protein kinase A and protein kinase C cross-talk. In this review, we provide an overview of the protective roles of a specific dopamine receptor subtype on renal oxidative stress, the different mechanisms involved in this effect, and the role of oxidative stress and impairment of dopamine receptor function in the hypertension that arises from the genetic ablation of a specific dopamine receptor gene in mice.
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Iijima K, Okudaira N, Tamura M, Doi A, Saito Y, Shimura M, Goto M, Matsunaga A, Kawamura YI, Otsubo T, Dohi T, Hoshino S, Kano S, Hagiwara S, Tanuma J, Gatanaga H, Baba M, Iguchi T, Yanagita M, Oka S, Okamura T, Ishizaka Y. Viral protein R of human immunodeficiency virus type-1 induces retrotransposition of long interspersed element-1. Retrovirology 2013; 10:83. [PMID: 23915234 PMCID: PMC3751050 DOI: 10.1186/1742-4690-10-83] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Accepted: 07/18/2013] [Indexed: 01/04/2023] Open
Abstract
Background Viral protein R (Vpr), a protein of human immunodeficiency virus type-1 (HIV-1) with various biological functions, was shown to be present in the blood of HIV-1-positive patients. However, it remained unclear whether circulating Vpr in patients’ blood is biologically active. Here, we examined the activity of blood Vpr using an assay system by which retrotransposition of long interspersed element-1 (L1-RTP) was detected. We also investigated the in vivo effects of recombinant Vpr (rVpr) by administrating it to transgenic mice harboring human L1 as a transgene (hL1-Tg mice). Based on our data, we discuss the involvement of blood Vpr in the clinical symptoms of acquired immunodeficiency syndrome (AIDS). Results We first discovered that rVpr was active in induction of L1-RTP. Biochemical analyses revealed that rVpr-induced L1-RTP depended on the aryl hydrocarbon receptor, mitogen-activated protein kinases, and CCAAT/enhancer-binding protein β. By using a sensitive L1-RTP assay system, we showed that 6 of the 15 blood samples from HIV-1 patients examined were positive for induction of L1-RTP. Of note, the L1-RTP-inducing activity was blocked by a monoclonal antibody specific for Vpr. Moreover, L1-RTP was reproducibly induced in various organs, including the kidney, when rVpr was administered to hL1-Tg mice. Conclusions Blood Vpr is biologically active, suggesting that its monitoring is worthwhile for clarification of the roles of Vpr in the pathogenesis of AIDS. This is the first report to demonstrate a soluble factor in patients’ blood active for L1-RTP activity, and implies the involvement of L1-RTP in the development of human diseases.
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Affiliation(s)
- Kenta Iijima
- Department of Intractable Diseases, Research Institute, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan
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Abstract
The kidney plays a fundamental role in maintaining body salt and fluid balance and blood pressure homeostasis through the actions of its proximal and distal tubular segments of nephrons. However, proximal tubules are well recognized to exert a more prominent role than distal counterparts. Proximal tubules are responsible for reabsorbing approximately 65% of filtered load and most, if not all, of filtered amino acids, glucose, solutes, and low molecular weight proteins. Proximal tubules also play a key role in regulating acid-base balance by reabsorbing approximately 80% of filtered bicarbonate. The purpose of this review article is to provide a comprehensive overview of new insights and perspectives into current understanding of proximal tubules of nephrons, with an emphasis on the ultrastructure, molecular biology, cellular and integrative physiology, and the underlying signaling transduction mechanisms. The review is divided into three closely related sections. The first section focuses on the classification of nephrons and recent perspectives on the potential role of nephron numbers in human health and diseases. The second section reviews recent research on the structural and biochemical basis of proximal tubular function. The final section provides a comprehensive overview of new insights and perspectives in the physiological regulation of proximal tubular transport by vasoactive hormones. In the latter section, attention is particularly paid to new insights and perspectives learnt from recent cloning of transporters, development of transgenic animals with knockout or knockin of a particular gene of interest, and mapping of signaling pathways using microarrays and/or physiological proteomic approaches.
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Affiliation(s)
- Jia L Zhuo
- Laboratory of Receptor and Signal Transduction, Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi, USA.
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Wang X, Escano CS, Asico L, Jones JE, Barte A, Lau YS, Jose PA, Armando I. Upregulation of renal D5 dopamine receptor ameliorates the hypertension in D3 dopamine receptor-deficient mice. Hypertension 2013; 62:295-301. [PMID: 23753418 DOI: 10.1161/hypertensionaha.113.01483] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
D3 dopamine receptor (D3R)-deficient mice have renin-dependent hypertension associated with sodium retention, but the hypertension is mild. To determine whether any compensatory mechanisms in the kidney are involved in the regulation of blood pressure with disruption of Drd3, we measured the renal protein expression of all dopamine receptor subtypes (D1R, D2R, D4R, and D5R) in D3R homozygous (D3(-/-)) and heterozygous (D3(+/-)) knockout mice and their wild-type (D3(+/+)) littermates. The renal immunohistochemistry and protein expression of D5R were increased (n=5/group) in D3(-/-) mice; renal D4R protein expression was decreased, whereas renal protein expressions of D1R and D2R were similar in both groups. Renal D5R protein expression was also increased in D3(+/-) (n=5/group) relative to D3(+/+) mice, whereas D1R, D2R, and D4R protein expressions were similar in D3(+/-) and D3(+/+) mice. The increase in renal D5R protein expression was abolished when D3(-/-) mice were fed a high-salt diet. Treatment with the D1-like receptor antagonist, SCH23390, increased the blood pressure in anesthetized D3(-/-) but not D3(+/+) mice (n=4/group), suggesting that the renal upregulation of D5R may have minimized the hypertension in D3(-/-) mice. The renal D5R protein upregulation was not caused by increased transcription because renal mRNA expression of D5R was similar in D3(-/-) and D3(+/+) mice. Our findings suggest that the renal upregulation of D5R may have minimized the hypertension that developed in D3(-/-) mice.
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Affiliation(s)
- Xiaoyan Wang
- Department of Medicine, University of Maryland, School of Medicine, 20 Penn St, Baltimore, MD 21201, USA.
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Rico EP, Rosemberg DB, Seibt KJ, Capiotti KM, Da Silva RS, Bonan CD. Zebrafish neurotransmitter systems as potential pharmacological and toxicological targets. Neurotoxicol Teratol 2011; 33:608-17. [PMID: 21907791 DOI: 10.1016/j.ntt.2011.07.007] [Citation(s) in RCA: 147] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Revised: 05/20/2011] [Accepted: 07/20/2011] [Indexed: 01/23/2023]
Abstract
Recent advances in neurobiology have emphasized the study of brain structure and function and its association with numerous pathological and toxicological events. Neurotransmitters are substances that relay, amplify, and modulate electrical signals between neurons and other cells. Neurotransmitter signaling mediates rapid intercellular communication by interacting with cell surface receptors, activating second messenger systems and regulating the activity of ion channels. Changes in the functional balance of neurotransmitters have been implicated in the failure of central nervous system function. In addition, abnormalities in neurotransmitter production or functioning can be induced by several toxicological compounds, many of which are found in the environment. The zebrafish has been increasingly used as an animal model for biomedical research, primarily due to its genetic tractability and ease of maintenance. These features make this species a versatile tool for pre-clinical drug discovery and toxicological investigations. Here, we present a review regarding the role of different excitatory and inhibitory neurotransmitter systems in zebrafish, such as dopaminergic, serotoninergic, cholinergic, purinergic, histaminergic, nitrergic, glutamatergic, glycinergic, and GABAergic systems, and emphasizing their features as pharmacological and toxicological targets. The increase in the global knowledge of neurotransmitter systems in zebrafish and the elucidation of their pharmacological and toxicological aspects may lead to new strategies and appropriate research priorities to offer insights for biomedical and environmental research.
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Affiliation(s)
- E P Rico
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2600-Anexo, Porto Alegre, RS, Brazil
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14
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Abstract
Dopamine is an important regulator of systemic blood pressure via multiple mechanisms. It affects fluid and electrolyte balance by its actions on renal hemodynamics and epithelial ion and water transport and by regulation of hormones and humoral agents. The kidney synthesizes dopamine from circulating or filtered L-DOPA independently from innervation. The major determinants of the renal tubular synthesis/release of dopamine are probably sodium intake and intracellular sodium. Dopamine exerts its actions via two families of cell surface receptors, D1-like receptors comprising D1R and D5R, and D2-like receptors comprising D2R, D3R, and D4R, and by interactions with other G protein-coupled receptors. D1-like receptors are linked to vasodilation, while the effect of D2-like receptors on the vasculature is variable and probably dependent upon the state of nerve activity. Dopamine secreted into the tubular lumen acts mainly via D1-like receptors in an autocrine/paracrine manner to regulate ion transport in the proximal and distal nephron. These effects are mediated mainly by tubular mechanisms and augmented by hemodynamic mechanisms. The natriuretic effect of D1-like receptors is caused by inhibition of ion transport in the apical and basolateral membranes. D2-like receptors participate in the inhibition of ion transport during conditions of euvolemia and moderate volume expansion. Dopamine also controls ion transport and blood pressure by regulating the production of reactive oxygen species and the inflammatory response. Essential hypertension is associated with abnormalities in dopamine production, receptor number, and/or posttranslational modification.
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Affiliation(s)
- Ines Armando
- Children’s National Medical Center—Center for Molecular Physiology Research, Washington, District of Columbia
| | - Van Anthony M. Villar
- Children’s National Medical Center—Center for Molecular Physiology Research, Washington, District of Columbia
| | - Pedro A. Jose
- Children’s National Medical Center—Center for Molecular Physiology Research, Washington, District of Columbia
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15
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Role of Gα(12)- and Gα(13)-protein subunit linkage of D(3) dopamine receptors in the natriuretic effect of D(3) dopamine receptor in kidney. Hypertens Res 2011; 34:1011-6. [PMID: 21633357 DOI: 10.1038/hr.2011.70] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The D(3) dopamine receptor is the major D(2)-like receptor that regulates sodium transport in the renal proximal tubule (RPT) and helps maintain blood pressure in the normal range. In Wistar-Kyoto (WKY) rats chronically fed high-salt diet, the intrarenal arterial infusion of a D(3) receptor agonist, PD128907, increased absolute and fractional sodium excretion. We have reported that Gα(12) and Gα(13), which participate in the signal transduction of the D(5) receptor, are expressed in RPTs. As the D(3) receptor is also expressed in RPTs, we hypothesized that it may also interact with Gα(12)/Gα(13) in RPTs from WKY rats. There were co-localization and co-immunoprecipitation of D(3) receptor and Gα(12)/Gα(13) in renal brush border membranes (BBMs) and RPT cells. The intrarenal infusion of PD128907 (1 μg kg(-1) min(-1)) that increased sodium excretion also increased the co-immunoprecipitations of D(3)/Gα(12) and D(3)/Gα(13) in renal BBMs; their co-immunoprecipitation was confirmed in RPT cells. As Gα(12) and Gα(13) increase sodium pump and transporter activity (for example, Na(+)-K(+)-ATPase, NHE3), an increased association of D(3) receptors with Gα(12)/Gα(13) receptors after D(3) receptor activation may be a mechanism to prevent Gα(12)/Gα(13)-mediated stimulation of sodium transport (and thus enhance natriuresis). We conclude that a D(3) receptor interaction with Gα(12)/Gα(13) that increases sodium excretion may have a role in the regulation of blood pressure.
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16
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Villar VAM, Jones JE, Armando I, Palmes-Saloma C, Yu P, Pascua AM, Keever L, Arnaldo FB, Wang Z, Luo Y, Felder RA, Jose PA. G protein-coupled receptor kinase 4 (GRK4) regulates the phosphorylation and function of the dopamine D3 receptor. J Biol Chem 2009; 284:21425-34. [PMID: 19520868 DOI: 10.1074/jbc.m109.003665] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
During conditions of moderate sodium excess, the dopaminergic system regulates blood pressure and water and electrolyte balance by engendering natriuresis. Dopamine exerts its effects on dopamine receptors, including the dopamine D(3) receptor. G protein-coupled receptor kinase 4 (GRK4), whose gene locus (4p16.3) is linked to essential hypertension, desensitizes the D(1) receptor, another dopamine receptor. This study evaluated the role of GRK4 on D(3) receptor function in human proximal tubule cells. D(3) receptor co-segregated in lipid rafts and co-immunoprecipitated and co-localized in human proximal tubule cells and in proximal and distal tubules and glomeruli of kidneys of Wistar Kyoto rats. Bimolecular fluorescence complementation and confocal microscopy revealed that agonist activation of the receptor initiated the interaction between D(3) receptor and GRK4 at the cell membrane and promoted it intracellularly, presumably en route to endosomal trafficking. Of the four GRK4 splice variants, GRK4-gamma and GRK4-alpha mediated a 3- and 2-fold increase in the phosphorylation of agonist-activated D(3) receptor, respectively. Inhibition of GRK activity with heparin or knockdown of GRK4 expression via RNA interference completely abolished p44/42 phosphorylation and mitogenesis induced by D(3) receptor stimulation. These data demonstrate that GRK4, specifically the GRK4-gamma and GRK4-alpha isoforms, phosphorylates the D(3) receptor and is crucial for its signaling in human proximal tubule cells.
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Affiliation(s)
- Van Anthony M Villar
- National Institute of Molecular Biology and Biotechnology, University of the Philippines, Diliman, Quezon City 1101, Philippines.
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17
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Wang X, Villar VAM, Armando I, Eisner GM, Felder RA, Jose PA. Dopamine, kidney, and hypertension: studies in dopamine receptor knockout mice. Pediatr Nephrol 2008; 23:2131-46. [PMID: 18615257 PMCID: PMC3724362 DOI: 10.1007/s00467-008-0901-3] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Revised: 04/18/2008] [Accepted: 05/07/2008] [Indexed: 02/06/2023]
Abstract
Dopamine is important in the pathogenesis of hypertension because of abnormalities in receptor-mediated regulation of renal sodium transport. Dopamine receptors are classified into D(1)-like (D(1), D(5)) and D(2)-like (D(2), D(3), D(4)) subtypes, all of which are expressed in the kidney. Mice deficient in specific dopamine receptors have been generated to provide holistic assessment on the varying physiological roles of each receptor subtype. This review examines recent studies on these mutant mouse models and evaluates the impact of individual dopamine receptor subtypes on blood pressure regulation.
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Affiliation(s)
- Xiaoyan Wang
- Department of Pediatrics, Georgetown University Medical Center, Washington, DC, USA
| | | | - Ines Armando
- Department of Pediatrics, Georgetown University Medical Center, Washington, DC, USA
| | - Gilbert M. Eisner
- Department of Medicine, Georgetown University Medical Center, Washington, DC, USA
| | - Robin A. Felder
- Department of Pathology, University of Virginia Health Sciences Center, Charlottesville, VA, USA
| | - Pedro A. Jose
- Department of Pediatrics, Georgetown University Medical Center, Washington, DC, USA
- Department of Physiology and Biophysics, Georgetown University Medical Center, Washington, DC, USA
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18
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Zeng C, Asico LD, Yu C, Villar VAM, Shi W, Luo Y, Wang Z, He D, Liu Y, Huang L, Yang C, Wang X, Hopfer U, Eisner GM, Jose PA. Renal D3 dopamine receptor stimulation induces natriuresis by endothelin B receptor interactions. Kidney Int 2008; 74:750-9. [PMID: 18547994 DOI: 10.1038/ki.2008.247] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Dopaminergic and endothelin systems participate in the control blood pressure by regulating sodium transport in the renal proximal tubule. Disruption of either the endothelin B receptor (ETB) or D(3) dopamine receptor gene in mice produces hypertension. To examine whether these two receptors interact we studied the Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats by selectively infusing reagents into the right kidney of anesthetized rats. The D(3) receptor agonist (PD128907) caused natriuresis in WKY rats which was partially blocked by the ETB receptor antagonist. In contrast, PD128907 blunted sodium excretion in the SHRs. We found using laser confocal microscopy that the ETB receptor was mainly located in the cell membrane in control WKY cells. Treatment with the D(3) receptor antagonist caused its internalization into intracellular compartments that contained the D(3) receptors. Combined use of D(3) and ETB antagonists failed to internalize ETB receptors in cells from WKY rats. In contrast in SHR cells, ETB receptors were found mainly in internal compartments under basal condition and thus were likely prevented from interacting with the agonist-stimulated, membrane-bound D(3) receptors. Our studies suggest that D(3) receptors physically interact with proximal tubule ETB receptors and that the blunted natriuretic effect of dopamine in SHRs may be explained, in part, by abnormal D(3)/ETB receptor interactions.
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Affiliation(s)
- Chunyu Zeng
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, PR China
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19
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Banday AA, Lau YS, Lokhandwala MF. Oxidative Stress Causes Renal Dopamine D1 Receptor Dysfunction and Salt-Sensitive Hypertension in Sprague-Dawley Rats. Hypertension 2008; 51:367-75. [DOI: 10.1161/hypertensionaha.107.102111] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Renal dopamine plays an important role in maintaining sodium homeostasis and blood pressure (BP) during increased sodium intake. The present study was carried out to determine whether renal dopamine D1 receptor (D1R) dysfunction contributes to increase in salt sensitivity during oxidative stress. Male Sprague-Dawley rats, divided into various groups, received tap water (vehicle); 1% NaCl (high salt [HS]);
l
-buthionine sulfoximine (BSO), an oxidant; and HS plus BSO with or without Tempol, an antioxidant, for 12 days. Compared with vehicle, HS intake increased urinary dopamine production and decreased basal renal Na/K-ATPase activity but did not affect BP. BSO-treated rats exhibited oxidative stress and a mild increase in BP. In these rats, D1R expression and G protein coupling were reduced, and SKF38393, a D1R agonist, failed to inhibit Na/K-ATPase activity and promote sodium excretion. Concomitant administration of BSO and HS caused oxidative stress, D1R dysfunction, and a marked increase in BP. Although renal dopamine production was increased, it failed to reduce the basal Na/K-ATPase activity in these animals. Treatment of BSO plus HS rats with Tempol decreased oxidative stress and restored endogenous, as well as exogenous, D1R agonist-mediated Na/K-ATPase inhibition and normalized BP. In conclusion, during HS intake, the increased dopamine production via Na/K-ATPase inhibition prevents an increase in BP. During oxidative stress, D1R function is defective, and there is mild hypertension. However, in the presence of oxidative stress, HS intake causes marked elevation in BP, which results from a defective renal D1R function leading to the failure of dopamine to inhibit Na/K-ATPase and promote sodium excretion.
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Affiliation(s)
- Anees A. Banday
- From the Heart and Kidney Institute, College of Pharmacy, University of Houston, Tex
| | - Yuen-Sum Lau
- From the Heart and Kidney Institute, College of Pharmacy, University of Houston, Tex
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20
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Zeng C, Armando I, Luo Y, Eisner GM, Felder RA, Jose PA. Dysregulation of dopamine-dependent mechanisms as a determinant of hypertension: studies in dopamine receptor knockout mice. Am J Physiol Heart Circ Physiol 2008; 294:H551-69. [PMID: 18083900 PMCID: PMC4029502 DOI: 10.1152/ajpheart.01036.2007] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Dopamine plays an important role in the pathogenesis of hypertension by regulating epithelial sodium transport and by interacting with vasoactive hormones/humoral factors, such as aldosterone, angiotensin, catecholamines, endothelin, oxytocin, prolactin pro-opiomelancortin, reactive oxygen species, renin, and vasopressin. Dopamine receptors are classified into D(1)-like (D(1) and D(5)) and D(2)-like (D(2), D(3), and D(4)) subtypes based on their structure and pharmacology. In recent years, mice deficient in one or more of the five dopamine receptor subtypes have been generated, leading to a better understanding of the physiological role of each of the dopamine receptor subtypes. This review summarizes the results from studies of various dopamine receptor mutant mice on the role of individual dopamine receptor subtypes and their interactions with other G protein-coupled receptors in the regulation of blood pressure.
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MESH Headings
- Animals
- Blood Pressure/genetics
- Blood Pressure/physiology
- Dopamine/physiology
- Hypertension/genetics
- Hypertension/physiopathology
- Mice
- Mice, Knockout
- Receptors, Dopamine/genetics
- Receptors, Dopamine/physiology
- Receptors, Dopamine D1/genetics
- Receptors, Dopamine D1/physiology
- Receptors, Dopamine D2/genetics
- Receptors, Dopamine D2/physiology
- Receptors, Dopamine D3/genetics
- Receptors, Dopamine D3/physiology
- Receptors, Dopamine D4/genetics
- Receptors, Dopamine D4/physiology
- Receptors, Dopamine D5/genetics
- Receptors, Dopamine D5/physiology
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Affiliation(s)
- Chunyu Zeng
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing City 400042, People's Republic of China.
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21
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Draper I, Kurshan PT, McBride E, Jackson FR, Kopin AS. Locomotor activity is regulated by D2-like receptors in Drosophila: an anatomic and functional analysis. Dev Neurobiol 2007; 67:378-93. [PMID: 17443795 DOI: 10.1002/dneu.20355] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In mammals, dopamine 2-like receptors are expressed in distinct pathways within the central nervous system, as well as in peripheral tissues. Selected neuronal D2-like receptors play a critical role in modulating locomotor activity and, as such, represent an important therapeutic target (e.g. in Parkinson's disease). Previous studies have established that proteins required for dopamine (DA) neurotransmission are highly conserved between mammals and the fruit fly Drosophila melanogaster. These include a fly dopamine 2-like receptor (DD2R; Hearn et al. PNAS 2002 99(22):14554) that has structural and pharmacologic similarity to the human D2-like (D2R). In the current study, we define the spatial expression pattern of DD2R, and functionally characterize flies with reduced DD2 receptor levels. We show that DD2R is expressed in the larval and adult nervous systems, in cell groups that include the Ap-let cohort of peptidergic neurons, as well as in peripheral tissues including the gut and Malpighian tubules. To examine DD2R function in vivo, we generated RNA-interference (RNAi) flies with reduced DD2R expression. Behavioral analysis revealed that these flies show significantly decreased locomotor activity, similar to the phenotype observed in mammals with reduced D2R expression. The fly RNAi phenotype can be rescued by administration of the DD2R synthetic agonist bromocriptine, indicating specificity for the RNAi effect. These results suggest Drosophila as a useful system for future studies aimed at identifying modifiers of dopaminergic signaling/locomotor function.
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Affiliation(s)
- Isabelle Draper
- Molecular Cardiology Research Institute, Tufts-New England Medical Center, Boston, Massachusetts, USA.
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22
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Abstract
Dopamine plays an important role in the pathogenesis of hypertension by regulating epithelial sodium transport, vascular smooth muscle contractility and production of reactive oxygen species and by interacting with the renin–angiotensin and sympathetic nervous systems. Dopamine receptors are classified into D1-like (D1 and D5) and D2-like (D2, D3 and D4) subtypes based on their structure and pharmacology. Each of the dopamine receptor subtypes participates in the regulation of blood pressure by mechanisms specific for the subtype. Some receptors regulate blood pressure by influencing the central and/or peripheral nervous system; others influence epithelial transport and regulate the secretion and receptors of several humoral agents. This review summarizes the physiology of the different dopamine receptors in the regulation of blood pressure, and the relationship between dopamine receptor subtypes and hypertension.
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MESH Headings
- Blood Pressure/physiology
- Dopamine/metabolism
- Gastrointestinal Tract/metabolism
- Gastrointestinal Tract/physiopathology
- Humans
- Hypertension/metabolism
- Hypertension/physiopathology
- Kidney/metabolism
- Kidney/physiopathology
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/physiopathology
- Receptors, Dopamine/metabolism
- Receptors, Dopamine/physiology
- Receptors, Dopamine D1/metabolism
- Receptors, Dopamine D1/physiology
- Receptors, Dopamine D2/metabolism
- Receptors, Dopamine D2/physiology
- Receptors, Dopamine D3/metabolism
- Receptors, Dopamine D3/physiology
- Receptors, Dopamine D4/metabolism
- Receptors, Dopamine D4/physiology
- Receptors, Dopamine D5/metabolism
- Receptors, Dopamine D5/physiology
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Affiliation(s)
- Chunyu Zeng
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing City, People's Republic of China.
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23
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Luippold G, Pech B, Schneider S, Drescher K, Müller R, Gross G, Mühlbauer B. Absence of amino acid-induced glomerular hyperfiltration in dopamine D3 receptor knockout mice. Naunyn Schmiedebergs Arch Pharmacol 2005; 372:284-90. [PMID: 16372190 DOI: 10.1007/s00210-005-0020-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2005] [Accepted: 10/17/2005] [Indexed: 11/29/2022]
Abstract
Pharmacological inhibition of receptors of the dopamine D2-like family has been shown to abolish the glomerular hyperfiltration in response to amino acids. To further discriminate between the receptor subtypes within the D2-like family, we investigated the effects of amino acid infusion on renal function in dopamine D3 receptor knockout (-/-) mice. In clearance experiments pentobarbital-anesthetized D3 receptor (-/-) and wild-type (+/+) mice were infused with Ringer solution at baseline, followed by a continuous infusion of mixed amino acids (10%). Baseline glomerular filtration rate (GFR), assessed by renal clearance of [3H]-inulin, was the same in D3 receptor (-/-) mice (0.56+/-0.08 ml/min per g kidney weight) and wild-type animals (0.56+/-0.04 ml/min per g kw). During infusion of amino acids, GFR was significantly elevated by 50% in D3 receptor (+/+) mice. In contrast, this amino acid-induced response of GFR was abolished in D3 receptor (-/-) mice. Baseline urinary water and sodium excretion was not significantly different in both groups of mice. As observed in GFR, these renal excretory parameters were significantly elevated during amino acid infusion in D3 receptor (+/+) but not in D3 receptor (-/-) mice. Time controls, constantly infused with Ringer solution, did not show significant changes in GFR, renal water or sodium excretion during the entire experiment, indicating stable experimental conditions. Taken together, the data underline the involvement of dopamine D2-like receptors in the renal response to amino acid infusion and, in addition, attribute this effect to the dopamine D3 receptor subtype.
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Affiliation(s)
- Gerd Luippold
- Department of Pharmacology, University of Tübingen, Wilhelmstrasse 56, 72074, Tübingen, Germany.
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