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Tyrosinase-Based Biosensors for Selective Dopamine Detection. SENSORS 2017; 17:s17061314. [PMID: 28590453 PMCID: PMC5492229 DOI: 10.3390/s17061314] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 05/30/2017] [Accepted: 06/01/2017] [Indexed: 11/17/2022]
Abstract
A novel tyrosinase-based biosensor was developed for the detection of dopamine (DA). For increased selectivity, gold electrodes were previously modified with cobalt (II)-porphyrin (CoP) film with electrocatalytic activity, to act both as an electrochemical mediator and an enzyme support, upon which the enzyme tyrosinase (Tyr) was cross-linked. Differential pulse voltammetry was used for electrochemical detection and the reduction current of dopamine-quinone was measured as a function of dopamine concentration. Our experiments demonstrated that the presence of CoP improves the selectivity of the electrode towards dopamine in the presence of ascorbic acid (AA), with a linear trend of concentration dependence in the range of 2–30 µM. By optimizing the conditioning parameters, a separation of 130 mV between the peak potentials for ascorbic acid AA and DA was obtained, allowing the selective detection of DA. The biosensor had a sensitivity of 1.22 ± 0.02 µA·cm−2·µM−1 and a detection limit of 0.43 µM. Biosensor performances were tested in the presence of dopamine medication, with satisfactory results in terms of recovery (96%), and relative standard deviation values below 5%. These results confirmed the applicability of the biosensors in real samples such as human urine and blood serum.
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Barati MT, Ketchem CJ, Merchant ML, Kusiak WB, Jose PA, Weinman EJ, LeBlanc AJ, Lederer ED, Khundmiri SJ. Loss of NHERF-1 expression prevents dopamine-mediated Na-K-ATPase regulation in renal proximal tubule cells from rat models of hypertension: aged F344 rats and spontaneously hypertensive rats. Am J Physiol Cell Physiol 2017; 313:C197-C206. [PMID: 28515088 DOI: 10.1152/ajpcell.00219.2016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 05/08/2017] [Accepted: 05/08/2017] [Indexed: 01/11/2023]
Abstract
Dopamine decreases Na-K-ATPase (NKA) activity by PKC-dependent phosphorylation and endocytosis of the NKA α1. Dopamine-mediated regulation of NKA is impaired in aging and some forms of hypertension. Using opossum (OK) proximal tubule cells (PTCs), we demonstrated that sodium-hydrogen exchanger regulatory factor-1 (NHERF-1) associates with NKA α1 and dopamine-1 receptor (D1R). This association is required for the dopamine-mediated regulation of NKA. In OK cells, dopamine decreases NHERF-1 association with NKA α1 but increases its association with D1R. However, it is not known whether NHERF-1 plays a role in dopamine-mediated NKA regulation in animal models of hypertension. We hypothesized that defective dopamine-mediated regulation of NKA results from the decrease in NHERF-1 expression in rat renal PTCs isolated from animal models of hypertension [spontaneously hypertensive rats (SHRs) and aged F344 rats]. To test this hypothesis, we isolated and cultured renal PTCs from 22-mo-old F344 rats and their controls, normotensive 4-mo-old F344 rats, and SHRs and their controls, normotensive Wistar-Kyoto (WKY) rats. The results demonstrate that in both hypertensive models (SHR and aged F344), NHERF-1 expression, dopamine-mediated phosphorylation of NKA, and ouabain-inhibitable K+ transport are reduced. Transfection of NHERF-1 into PTCs from aged F344 and SHRs restored dopamine-mediated inhibition of NKA. These results suggest that decreased renal NHERF-1 expression contributes to the impaired dopamine-mediated inhibition of NKA in PTCs from animal models of hypertension.
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Affiliation(s)
- Michelle T Barati
- Department of Medicine, Nephrology and Hypertension, University of Louisville, Louisville, Kentucky
| | - Corey J Ketchem
- Department of Medicine, Nephrology and Hypertension, University of Louisville, Louisville, Kentucky
| | - Michael L Merchant
- Department of Medicine, Nephrology and Hypertension, University of Louisville, Louisville, Kentucky
| | - Walter B Kusiak
- Department of Medicine, Nephrology and Hypertension, University of Louisville, Louisville, Kentucky
| | - Pedro A Jose
- Department of Medicine, Division of Renal Diseases and Hypertension, and Department of Pharmacology and Physiology, The George Washington University, Washington, District of Columbia
| | - Edward J Weinman
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Amanda J LeBlanc
- Department of Physiology, University of Louisville, Louisville, Kentucky
| | - Eleanor D Lederer
- Department of Medicine, Nephrology and Hypertension, University of Louisville, Louisville, Kentucky.,Department of Physiology, University of Louisville, Louisville, Kentucky.,Robley Rex VA Medical Center, Louisville, Kentucky; and
| | - Syed J Khundmiri
- Department of Physiology and Biophysics, Howard University College of Medicine, Washington, District of Columbia
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Jiang X, Zhang Y, Yang Y, Yang J, Asico LD, Chen W, Felder RA, Armando I, Jose PA, Yang Z. Gastrin stimulates renal dopamine production by increasing the renal tubular uptake of l-DOPA. Am J Physiol Endocrinol Metab 2017; 312:E1-E10. [PMID: 27780818 PMCID: PMC5283882 DOI: 10.1152/ajpendo.00116.2016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 10/18/2016] [Accepted: 10/23/2016] [Indexed: 01/02/2023]
Abstract
Gastrin is a peptide hormone that is involved in the regulation of sodium balance and blood pressure. Dopamine, which is also involved in the regulation of sodium balance and blood pressure, directly or indirectly interacts with other blood pressure-regulating hormones, including gastrin. This study aimed to determine the mechanisms of the interaction between gastrin and dopamine and tested the hypothesis that gastrin produced in the kidney increases renal dopamine production to keep blood pressure within the normal range. We show that in human and mouse renal proximal tubule cells (hRPTCs and mRPTCs, respectively), gastrin stimulates renal dopamine production by increasing the cellular uptake of l-DOPA via the l-type amino acid transporter (LAT) at the plasma membrane. The uptake of l-DOPA in RPTCs from C57Bl/6J mice is lower than in RPTCs from normotensive humans. l-DOPA uptake in renal cortical slices is also lower in salt-sensitive C57Bl/6J than in salt-resistant BALB/c mice. The deficient renal cortical uptake of l-DOPA in C57Bl/6J mice may be due to decreased LAT-1 activity that is related to its decreased expression at the plasma membrane, relative to BALB/c mice. We also show that renal-selective silencing of Gast by the renal subcapsular injection of Gast siRNA in BALB/c mice decreases renal dopamine production and increases blood pressure. These results highlight the importance of renal gastrin in stimulating renal dopamine production, which may give a new perspective in the prevention and treatment of hypertension.
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MESH Headings
- Amino Acid Transport System y+L/drug effects
- Amino Acid Transport System y+L/metabolism
- Animals
- Blood Pressure/drug effects
- Blood Pressure/physiology
- Cells, Cultured
- Dopamine/biosynthesis
- Dopamine/urine
- Down-Regulation
- Gastrins/genetics
- Gastrins/metabolism
- Gastrins/pharmacology
- Gene Silencing
- Humans
- Immunoblotting
- Kidney/drug effects
- Kidney/metabolism
- Kidney Cortex/drug effects
- Kidney Cortex/metabolism
- Kidney Tubules, Proximal/cytology
- Kidney Tubules, Proximal/drug effects
- Kidney Tubules, Proximal/metabolism
- Levodopa/metabolism
- Male
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- RNA, Messenger/drug effects
- RNA, Messenger/metabolism
- RNA, Small Interfering
- Real-Time Polymerase Chain Reaction
- Receptor, Cholecystokinin B/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
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Affiliation(s)
- Xiaoliang Jiang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) and Comparative Medicine Centre, Peking Union Medical, Beijing, China
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Yanrong Zhang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) and Comparative Medicine Centre, Peking Union Medical, Beijing, China
| | - Yu Yang
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland;
- Department of Pathology, The University of Texas Medical Branch, Galveston, Texas
| | - Jian Yang
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland;
- Department of Cardiology, Daping Hospital, The Third Military Medical University and Chongqing Institute of Cardiology, Chongqing, China
| | - Laureano D Asico
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Wei Chen
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) and Comparative Medicine Centre, Peking Union Medical, Beijing, China
| | - Robin A Felder
- Department of Pathology, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Ines Armando
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Pedro A Jose
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
- Department of Medicine, Division of Kidney Disease and Hypertension, The George Washington University School of Medicine and Health Sciences, Washington, DC; and
- Department of Pharmacology and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC
| | - Zhiwei Yang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) and Comparative Medicine Centre, Peking Union Medical, Beijing, China;
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Huang H, Li X, Zheng S, Chen Y, Chen C, Wang J, Tong H, Zhou L, Yang J, Zeng C. Downregulation of Renal G Protein-Coupled Receptor Kinase Type 4 Expression via Ultrasound-Targeted Microbubble Destruction Lowers Blood Pressure in Spontaneously Hypertensive Rats. J Am Heart Assoc 2016; 5:e004028. [PMID: 27792639 PMCID: PMC5121504 DOI: 10.1161/jaha.116.004028] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 09/01/2016] [Indexed: 12/18/2022]
Abstract
BACKGROUND G protein-coupled receptor kinase type 4 (GRK4) plays a vital role in the long-term control of blood pressure (BP) and sodium excretion by regulating renal G protein-coupled receptor phosphorylation, including dopamine type 1 receptor (D1R). Ultrasound-targeted microbubble destruction (UTMD) is a promising method for gene delivery. Whether this method can deliver GRK4 small interfering RNA (siRNA) and lower BP is not known. METHODS AND RESULTS BP, 24-hour sodium excretion, and urine volume were measured after UTMD-targeted GRK4 siRNA delivery to the kidney in spontaneously hypertensive rats. The expression levels of GRK4 and D1R were determined by immunoblotting. The phosphorylation of D1R was investigated using immunoprecipitation. The present study revealed that UTMD-mediated renal GRK4 siRNA delivery efficiently reduced GRK4 expression and lowered BP in spontaneously hypertensive rats, accompanied by increased sodium excretion. The increased sodium excretion might be accounted for by the UTMD regulation of D1R phosphorylation and function in spontaneously hypertensive rats. Further analysis showed that, although UTMD had no effect on D1R expression, it reduced D1R phosphorylation in spontaneously hypertensive rats kidneys and consequently increased D1R-mediated natriuresis and diuresis. CONCLUSIONS Taken together, these study results indicate that UTMD-targeted GRK4 siRNA delivery to the kidney effectively reduces D1R phosphorylation by inhibiting renal GRK4 expression, improving D1R-mediated natriuresis and diuresis, and lowering BP, which may provide a promising novel strategy for gene therapy for hypertension.
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Affiliation(s)
- Hefei Huang
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China Chongqing Institute of Cardiology & Chongqing Cardiovascular Clinical Research Center, Chongqing, China
| | - Xiaolong Li
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China Chongqing Institute of Cardiology & Chongqing Cardiovascular Clinical Research Center, Chongqing, China Department of Cardiology, The First Affiliated Hospital, Shantou Medical College, Shantou, China
| | - Shuo Zheng
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China Chongqing Institute of Cardiology & Chongqing Cardiovascular Clinical Research Center, Chongqing, China
| | - Yue Chen
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China Chongqing Institute of Cardiology & Chongqing Cardiovascular Clinical Research Center, Chongqing, China
| | - Caiyu Chen
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China Chongqing Institute of Cardiology & Chongqing Cardiovascular Clinical Research Center, Chongqing, China
| | - Jialiang Wang
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China Chongqing Institute of Cardiology & Chongqing Cardiovascular Clinical Research Center, Chongqing, China
| | - Haipeng Tong
- Department of Radiology, Daping Hospital, The Third Military Medical University, Chongqing, China
| | - Lin Zhou
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China Chongqing Institute of Cardiology & Chongqing Cardiovascular Clinical Research Center, Chongqing, China
| | - Jian Yang
- Department of Nutrition, Daping Hospital, The Third Military Medical University, Chongqing, China
| | - Chunyu Zeng
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, China Chongqing Institute of Cardiology & Chongqing Cardiovascular Clinical Research Center, Chongqing, China
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Wehrwein EA, Orer HS, Barman SM. Overview of the Anatomy, Physiology, and Pharmacology of the Autonomic Nervous System. Compr Physiol 2016; 6:1239-78. [PMID: 27347892 DOI: 10.1002/cphy.c150037] [Citation(s) in RCA: 235] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Comprised of the sympathetic nervous system, parasympathetic nervous system, and enteric nervous system, the autonomic nervous system (ANS) provides the neural control of all parts of the body except for skeletal muscles. The ANS has the major responsibility to ensure that the physiological integrity of cells, tissues, and organs throughout the entire body is maintained (homeostasis) in the face of perturbations exerted by both the external and internal environments. Many commonly prescribed drugs, over-the-counter drugs, toxins, and toxicants function by altering transmission within the ANS. Autonomic dysfunction is a signature of many neurological diseases or disorders. Despite the physiological relevance of the ANS, most neuroscience textbooks offer very limited coverage of this portion of the nervous system. This review article provides both historical and current information about the anatomy, physiology, and pharmacology of the sympathetic and parasympathetic divisions of the ANS. The ultimate aim is for this article to be a valuable resource for those interested in learning the basics of these two components of the ANS and to appreciate its importance in both health and disease. Other resources should be consulted for a thorough understanding of the third division of the ANS, the enteric nervous system. © 2016 American Physiological Society. Compr Physiol 6:1239-1278, 2016.
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Affiliation(s)
- Erica A Wehrwein
- Department of Physiology, Michigan State University, East Lansing, Michigan, USA
| | - Hakan S Orer
- Department of Pharmacology, Koc University School of Medicine, Istanbul, Turkey
| | - Susan M Barman
- Department of Pharmacology &Toxicology, Michigan State University, East Lansing, Michigan, USA
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56
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Affiliation(s)
- Pedro A Jose
- From the Departments of Medicine and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC (P.A.J.); Department of Pathology, The University of Virginia, Charlottesville (R.A.F.); Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Centre, Peking Union Medical College, Beijing, P.R. China (Z.Y.); Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, P.R. China (C.Z.); and Department of Medicine, Georgetown University Medical Center, Washington, DC (G.M.E.).
| | - Robin A Felder
- From the Departments of Medicine and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC (P.A.J.); Department of Pathology, The University of Virginia, Charlottesville (R.A.F.); Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Centre, Peking Union Medical College, Beijing, P.R. China (Z.Y.); Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, P.R. China (C.Z.); and Department of Medicine, Georgetown University Medical Center, Washington, DC (G.M.E.)
| | - Zhiwei Yang
- From the Departments of Medicine and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC (P.A.J.); Department of Pathology, The University of Virginia, Charlottesville (R.A.F.); Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Centre, Peking Union Medical College, Beijing, P.R. China (Z.Y.); Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, P.R. China (C.Z.); and Department of Medicine, Georgetown University Medical Center, Washington, DC (G.M.E.)
| | - Chunyu Zeng
- From the Departments of Medicine and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC (P.A.J.); Department of Pathology, The University of Virginia, Charlottesville (R.A.F.); Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Centre, Peking Union Medical College, Beijing, P.R. China (Z.Y.); Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, P.R. China (C.Z.); and Department of Medicine, Georgetown University Medical Center, Washington, DC (G.M.E.)
| | - Gilbert M Eisner
- From the Departments of Medicine and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC (P.A.J.); Department of Pathology, The University of Virginia, Charlottesville (R.A.F.); Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Centre, Peking Union Medical College, Beijing, P.R. China (Z.Y.); Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing, P.R. China (C.Z.); and Department of Medicine, Georgetown University Medical Center, Washington, DC (G.M.E.)
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Jose PA, Yang Z, Zeng C, Felder RA. The importance of the gastrorenal axis in the control of body sodium homeostasis. Exp Physiol 2016; 101:465-70. [PMID: 26854262 DOI: 10.1113/ep085286] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 02/01/2016] [Indexed: 12/27/2022]
Abstract
NEW FINDINGS What is the topic of this review? Sensing the amount of ingested sodium is one mechanism by which sodium balance is regulated. This review describes the role of gastrin in the cross-talk between the stomach and the kidney following the ingestion of sodium. What advances does it highlight? Neural mechanisms and several gut hormones, including cholecystokinin and uroguanylin, have been suggested to mediate the natriuresis after an oral sodium load. It is proposed that gastrin produced by G-cells via its receptor, cholecystokinin B receptor, interacts with renal D1 -like dopamine receptors to increase renal sodium excretion. Hypertension develops with chronically increased sodium intake when sodium that accumulates in the body can no longer be sequestered, extracellular fluid volume is expanded, and compensatory neural, hormonal and pressure-natriuresis mechanisms fail. Sensing the amount of ingested sodium, by the stomach, is one mechanism by which sodium balance is regulated. The natriuresis following the ingestion of a certain amount of sodium may be due to an enterokine, gastrin, secreted by G-cells in the stomach and duodenum and released into the circulation. Circulating gastrin levels are 10- to 20-fold higher than those for cholecystokinin. Of all the gut hormones circulating in the plasma, gastrin is the one that is reabsorbed to the greatest extent by renal tubules. Gastrin, via its receptor, the cholecystokinin type B receptor (CCKBR), is natriuretic in mammals, including humans, by inhibition of renal sodium transport. Germline deletion of gastrin (Gast) or Cckbr gene in mice causes salt-sensitive hypertension. Selective silencing of Gast in the stomach and duodenum impairs the ability to excrete an oral sodium load and also increases blood pressure. Thus, the gastrorenal axis, mediated by gastrin, can complement pronatriuretic hormones, such as dopamine, to increase sodium excretion after an oral sodium load. These studies in mice may be translatable to humans because the chromosomal loci of CCKBR and GAST are linked to human essential hypertension. Understanding the role of genes in the regulation of renal function and blood pressure may lead to the tailoring of antihypertensive treatment based on genetic make-up.
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Affiliation(s)
- Pedro A Jose
- Department of Medicine, The George Washington University School of Medicine, Washington, DC, USA.,Department of Physiology, The George Washington University School of Medicine, Washington, DC, USA
| | - Zhiwei Yang
- Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences & Comparative Medicine Centre, Peking Union Medical College, Beijing, PR China
| | - Chunyu Zeng
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing Institute of Cardiology, Chongqing 400042, PR China
| | - Robin A Felder
- Department of Pathology, The University of Virginia, Charlottesville, VA, USA
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Zhang Y, Jiang X, Qin C, Cuevas S, Jose PA, Armando I. Dopamine D2 receptors' effects on renal inflammation are mediated by regulation of PP2A function. Am J Physiol Renal Physiol 2016; 310:F128-34. [PMID: 26290374 PMCID: PMC4719046 DOI: 10.1152/ajprenal.00453.2014] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 06/15/2015] [Indexed: 01/11/2023] Open
Abstract
Lack or downregulation of the dopamine D2 receptor (D2R) results in increased renal expression of injury markers and proinflammatory factors that is independent of a blood pressure increase. This study aimed to determine the mechanisms involved in the regulation of renal inflammation by D2Rs. Silencing D2Rs in mouse renal proximal tubule cells increased the expression of the proinflammatory TNF-α, monocyte chemoattractant protein-1 (MCP-1), and IL-6. D2R downregulation also increased Akt phosphorylation and activity, and glycogen synthase kinase-3β (GSK3β) phosphorylation and cyclin D1 expression, downstream targets of Akt; however. phosphatidylinositol 3-kinase (PI3K) activity was not affected. Conversely, D2R stimulation decreased Akt and GSK3β phosphorylation and cyclin D1 expression. Increased phospho-Akt, in the absence of increased PI3K activity, may result from decreased Akt dephosphorylation. Inhibition of protein phosphatase 2A (PP2A) with okadaic acid reproduced the effects of D2R downregulation on Akt, GSK3β, and cyclin D1. The PP2A catalytic subunit and regulatory subunit PPP2R2C coimmunoprecipitated with the D2R. Basal phosphatase activity and the expression of PPP2R2C were decreased by D2R silencing that also blunted the increase in phosphatase activity induced by D2R stimulation. Similarly, silencing PPP2R2C also increased the phosphorylation of Akt and GSK3β. Moreover, downregulation of PPP2R2C resulted in increased expression of TNF-α, MCP-1, and IL-6, indicating that decreased phosphatase activity may be responsible for the D2R effect on inflammatory factors. Indeed, the increase in NF-κB reporter activity induced by D2R silencing was blunted by increasing PP2A activity with protamine. Our results show that D2R controls renal inflammation, at least in part, by modulation of the Akt pathway through effects on PP2A activity/expression.
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Affiliation(s)
- Yanrong Zhang
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland; Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) and Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China; and
| | - Xiaoliang Jiang
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland; Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) and Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China; and
| | - Chuan Qin
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland; Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences (CAMS) and Comparative Medicine Centre, Peking Union Medical Collage (PUMC), Beijing, P. R. China; and
| | - Santiago Cuevas
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Pedro A Jose
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland; Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Ines Armando
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
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Abstract
PURPOSE OF REVIEW This review will highlight recent findings concerning the regulation and signalling of the intrarenal dopaminergic system and the emerging evidence for its importance in blood pressure regulation. RECENT FINDINGS There is an increasing evidence that the intrarenal dopaminergic system plays an important role in the regulation of blood pressure, and defects in dopamine signalling appear to be involved in the development of hypertension. Recent experimental models have definitively demonstrated that abnormalities in intrarenal dopamine production or receptor signalling can predispose to salt-sensitive hypertension and a dysregulated renin-angiotensin system. There are also new results indicating the importance of dopamine receptor mediated regulation of salt and water homeostasis along the nephron, and new studies indicating the role that the intrarenal dopaminergic system plays to mitigate the production of reactive oxygen species and progression of chronic renal disease. SUMMARY New studies underscore the importance of the intrarenal dopaminergic system in the regulation of renal function and indicate how alterations in dopamine production or signalling may underlie the development of hypertension and kidney injury.
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60
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Appel NM, Li SH, Holmes TH, Acri JB. Dopamine D3 Receptor Antagonist (GSK598809) Potentiates the Hypertensive Effects of Cocaine in Conscious, Freely-Moving Dogs. J Pharmacol Exp Ther 2015; 354:484-92. [PMID: 26177654 DOI: 10.1124/jpet.115.224121] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 07/14/2015] [Indexed: 12/12/2022] Open
Abstract
The chronic and relapsing nature of addiction presents unique challenges for ensuring the safety of a potential medication. A patient may use cocaine, for example, while taking the medication or take more medication than prescribed. Thus, a potential medication must be safe and not exacerbate the effects of cocaine. Multiple published studies support antagonism of brain dopamine D3 receptor function as a potential mechanism of action for an anti-addiction medication. Dopamine D3 receptors are widely distributed outside the central nervous system, however; for example, dopamine D3 receptors in the kidneys are implicated in regulating blood pressure. The selective dopamine D3 receptor antagonist GSK598809 [1-(2-fluoro-4-trifluoromethyl-phenyl)-3-{3-[4-methyl-5-(4-methyl-oxazol-5-yl)-4H-[1,2,4]triazol-3-ylsulfanyl]-propyl}-3-aza-bicyclo[3.1.0]hexane] has been proposed as a medication to treat cocaine and other substance use disorders. The US Food and Drug Administration has established guidelines recommending safety studies to investigate potential undesirable pharmacodynamic effects of a substance in relation to exposure in the therapeutic range and above. Hence, we assessed the interaction between this selective dopamine D3 receptor antagonist and cocaine on hemodynamics and cardiac function in freely-moving, telemetered dogs before conducting a clinical trial. GSK598809 increased the hemodynamic effect of cocaine in this model. Thus, the increase in blood pressure after intravenous cocaine was greater in animals that had been pretreated with GSK598809 compared with vehicle. This finding suggests that GSK598809 in particular, and perhaps dopamine D3 receptor antagonists as a class, may produce unacceptable cardiovascular risks as medications to treat cocaine use disorder.
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Affiliation(s)
- Nathan M Appel
- Division of Pharmacotherapies and Medical Consequences of Drug Abuse, National Institute on Drug Abuse, National Institutes of Health, Bethesda, Maryland (N.M.A., S.-H.L., J.B.A.); and Stanford Center for Sleep Sciences and Medicine, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California (T.H.H.)
| | - Shou-Hua Li
- Division of Pharmacotherapies and Medical Consequences of Drug Abuse, National Institute on Drug Abuse, National Institutes of Health, Bethesda, Maryland (N.M.A., S.-H.L., J.B.A.); and Stanford Center for Sleep Sciences and Medicine, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California (T.H.H.)
| | - Tyson H Holmes
- Division of Pharmacotherapies and Medical Consequences of Drug Abuse, National Institute on Drug Abuse, National Institutes of Health, Bethesda, Maryland (N.M.A., S.-H.L., J.B.A.); and Stanford Center for Sleep Sciences and Medicine, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California (T.H.H.)
| | - Jane B Acri
- Division of Pharmacotherapies and Medical Consequences of Drug Abuse, National Institute on Drug Abuse, National Institutes of Health, Bethesda, Maryland (N.M.A., S.-H.L., J.B.A.); and Stanford Center for Sleep Sciences and Medicine, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California (T.H.H.)
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Abstract
Acute cardiorenal syndrome, also known as cardiorenal syndrome type 1, is defined as an abrupt worsening of cardiac function that occurs in at least 30 % of patients with acute decompensated heart failure and can lead to the development of acute kidney injury. The changes in renal function that occur in this setting have variable prognostic implications, as both poorer and better outcomes have been reported when renal function worsens during treatment of heart failure decompensation. Furthermore, it remains unclear when worsening renal function is actually a manifestation of true acute kidney injury or simply an indicator of hemoconcentration. Given these gaps in the understanding of the significance of renal function changes in the setting of decompensated heart failure, it is not surprising that studies on the effects of available therapies, including diuretics, vasoactive drugs, and mechanical fluid removal have yielded inconsistent results. The purpose of this review is to analyze critically the current knowledge on the pathophysiology, epidemiology, prognosis, and treatment of acute cardiorenal syndrome.
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Li F, Yang J, Jones JE, Villar VAM, Yu P, Armando I, Felder RA, Jose PA. Sorting nexin 5 and dopamine d1 receptor regulate the expression of the insulin receptor in human renal proximal tubule cells. Endocrinology 2015; 156:2211-21. [PMID: 25825816 PMCID: PMC4430625 DOI: 10.1210/en.2014-1638] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Sorting nexin 5 (SNX5) belongs to the SNX family, which is composed of a diverse group of proteins that mediate trafficking of plasma membrane proteins, receptors, and transporters. SNX5 is important in the resensitization of the dopamine D1-like receptor (D1R). D1R is uncoupled from its effector proteins in hypertension and diabetes, and treatment of diabetes restores D1R function and insulin receptor (IR) expression. We tested the hypothesis that the D1R and SNX5 regulate IR by studying the expression, distribution, dynamics, and functional consequences of their interaction in human renal proximal tubule cells (hRPTCs). D1R, SNX5, and IR were expressed and colocalized in the brush border of RPTs. Insulin promoted the colocalization of SNX5 and IR at the perinuclear area of hRPTCs. Unlike SNX5, the D1R colocalized and coimmunoprecipitated with IR, and this interaction was enhanced by insulin. To evaluate the role of SNX5 and D1R on IR signaling, we silenced via RNA interference the endogenous expression of SNX5 or the D1R gene DRD1 in hRPTCs. We observed a decrease in IR expression and abundance of phosphorylated IR substrate and phosphorylated protein kinase B, which are crucial components of the IR signal transduction pathway. Our data indicate that SNX5 and D1R are necessary for normal IR expression and activity. It is conceivable that D1R and SNX5 may interact to increase the sensitivity to insulin via a positive regulation of IR and insulin signaling.
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Affiliation(s)
- Fengmin Li
- Department of Physiology and Biophysics (F.L., P.A.J.), Georgetown University Medical Center, Washington, DC 20057; Liver Disease Branch (F.L.), National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892; Department of Nutrition (J.Y.), Daping Hospital, The Third Military Medical University, Chongqing 400042, People's Republic of China; Division of Nephrology (J.Y.J.E.J., V.A.M.V., P.Y., I.A., P.A.J.), Department of Medicine, and Department of Physiology (P.A.J.), University of Maryland School of Medicine, Baltimore, Maryland 21201; and University of Virginia Health Sciences Center (R.A.F.), Charlottesville, Virginia 22908
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Cuevas S, Yang Y, Konkalmatt P, Asico LD, Feranil J, Jones J, Villar VA, Armando I, Jose PA. Role of nuclear factor erythroid 2-related factor 2 in the oxidative stress-dependent hypertension associated with the depletion of DJ-1. Hypertension 2015; 65:1251-7. [PMID: 25895590 DOI: 10.1161/hypertensionaha.114.04525] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 03/26/2015] [Indexed: 01/11/2023]
Abstract
Renal dopamine 2 receptor dysfunction is associated with oxidative stress and high blood pressure (BP). We have reported that DJ-1, an oxidative stress response protein, is positively regulated by dopamine 2 receptor in the kidney. The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) regulates the expression of several antioxidant genes. We tested the hypothesis that Nrf2 is involved in the renal DJ-1-mediated inhibition of reactive oxygen species production. We have reported that silencing dopamine 2 receptor in mouse renal proximal tubule cells decreases the expression of DJ-1. We now report that silencing DJ-1 or dopamine 2 receptor in mouse proximal tubule cells and mouse kidneys decreases Nrf2 expression and activity and increases reactive oxygen species production; BP is also increased in mice in which renal DJ-1 or dopamine 2 receptor is silenced. DJ-1(-/-) mice have decreased renal Nrf2 expression and activity and increased nitro-tyrosine levels and BP. Silencing Nrf2 in mouse proximal tubule cells does not alter the expression of DJ-1 or dopamine 2 receptor, indicating that Nrf2 is downstream of dopamine 2 receptor and DJ-1. An Nrf2 inducer, bardoxolone, normalizes the systolic BP and renal malondialdehyde levels in DJ-1(-/-) mice without affecting them in their wild-type littermates. Because Nrf2 ubiquitination is increased in DJ-1(-/-) mice, we conclude that the protective effect of DJ-1 on renal oxidative stress is mediated, in part, by preventing Nrf2 degradation. Moreover, renal dopamine 2 receptor and DJ-1 are necessary for normal Nrf2 activity to keep a normal redox balance and BP.
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Affiliation(s)
- Santiago Cuevas
- From the Department of Medicine, Division of Nephrology (S.C., Y.Y., P.K., L.D.A., J.F., J.J., V.A.V., I.A., P.A.J.) and Department of Physiology (P.A.J.), University of Maryland School of Medicine, Baltimore.
| | - Yu Yang
- From the Department of Medicine, Division of Nephrology (S.C., Y.Y., P.K., L.D.A., J.F., J.J., V.A.V., I.A., P.A.J.) and Department of Physiology (P.A.J.), University of Maryland School of Medicine, Baltimore
| | - Prasad Konkalmatt
- From the Department of Medicine, Division of Nephrology (S.C., Y.Y., P.K., L.D.A., J.F., J.J., V.A.V., I.A., P.A.J.) and Department of Physiology (P.A.J.), University of Maryland School of Medicine, Baltimore
| | - Laureano D Asico
- From the Department of Medicine, Division of Nephrology (S.C., Y.Y., P.K., L.D.A., J.F., J.J., V.A.V., I.A., P.A.J.) and Department of Physiology (P.A.J.), University of Maryland School of Medicine, Baltimore
| | - Jun Feranil
- From the Department of Medicine, Division of Nephrology (S.C., Y.Y., P.K., L.D.A., J.F., J.J., V.A.V., I.A., P.A.J.) and Department of Physiology (P.A.J.), University of Maryland School of Medicine, Baltimore
| | - John Jones
- From the Department of Medicine, Division of Nephrology (S.C., Y.Y., P.K., L.D.A., J.F., J.J., V.A.V., I.A., P.A.J.) and Department of Physiology (P.A.J.), University of Maryland School of Medicine, Baltimore
| | - Van Anthony Villar
- From the Department of Medicine, Division of Nephrology (S.C., Y.Y., P.K., L.D.A., J.F., J.J., V.A.V., I.A., P.A.J.) and Department of Physiology (P.A.J.), University of Maryland School of Medicine, Baltimore
| | - Ines Armando
- From the Department of Medicine, Division of Nephrology (S.C., Y.Y., P.K., L.D.A., J.F., J.J., V.A.V., I.A., P.A.J.) and Department of Physiology (P.A.J.), University of Maryland School of Medicine, Baltimore
| | - Pedro A Jose
- From the Department of Medicine, Division of Nephrology (S.C., Y.Y., P.K., L.D.A., J.F., J.J., V.A.V., I.A., P.A.J.) and Department of Physiology (P.A.J.), University of Maryland School of Medicine, Baltimore
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Keck TM, John WS, Czoty PW, Nader MA, Newman AH. Identifying Medication Targets for Psychostimulant Addiction: Unraveling the Dopamine D3 Receptor Hypothesis. J Med Chem 2015; 58:5361-80. [PMID: 25826710 PMCID: PMC4516313 DOI: 10.1021/jm501512b] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The dopamine D3 receptor (D3R) is a target for developing medications to treat substance use disorders. D3R-selective compounds with high affinity and varying efficacies have been discovered, providing critical research tools for cell-based studies that have been translated to in vivo models of drug abuse. D3R antagonists and partial agonists have shown especially promising results in rodent models of relapse-like behavior, including stress-, drug-, and cue-induced reinstatement of drug seeking. However, to date, translation to human studies has been limited. Herein, we present an overview and illustrate some of the pitfalls and challenges of developing novel D3R-selective compounds toward clinical utility, especially for treatment of cocaine abuse. Future research and development of D3R-selective antagonists and partial agonists for substance abuse remains critically important but will also require further evaluation and development of translational animal models to determine the best time in the addiction cycle to target D3Rs for optimal therapeutic efficacy.
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Affiliation(s)
- Thomas M Keck
- †Medicinal Chemistry Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse-Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - William S John
- §Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157-1083, United States
| | - Paul W Czoty
- §Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157-1083, United States
| | - Michael A Nader
- §Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157-1083, United States
| | - Amy Hauck Newman
- †Medicinal Chemistry Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse-Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
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Yang S, Yang Y, Yu P, Yang J, Jiang X, Villar VAM, Sibley DR, Jose PA, Zeng C. Dopamine D1 and D5 receptors differentially regulate oxidative stress through paraoxonase 2 in kidney cells. Free Radic Res 2015; 49:397-410. [PMID: 25740199 DOI: 10.3109/10715762.2015.1006215] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND The renal dopaminergic system plays an important role in the pathogenesis of hypertension. Dopamine D1-like receptors (D1R and D5R) decrease reactive oxygen species (ROS) production via inhibition of pro-oxidant enzymes such as NADPH oxidase. Paraoxonase 2 (PON2) is also involved in the inhibition of NADPH oxidase activity. Therefore, we tested the hypothesis that D1R and D5R inhibit ROS production by increasing the expression of PON2, including those in membrane microdomains. METHODS AND RESULTS PON2 colocalized with D1R and D5R in mouse renal proximal tubules (RPTs), human RPT (hRPT) cells, and HEK293 cells heterologously expressing human D1R (HEK-hD1R) or D5R (HEK-hD5R). Fenoldopam, an agonist for both D1R and D5R, increased PON2 co-immunoprecipitation with D1R and D5R in HEK-hD1R and HEK-hD5R cells, respectively. Silencing PON2 increased ROS production and NADPH oxidase activity, and impaired the inhibitory effect of fenoldopam. Fenoldopam increased PON2 protein in both lipid rafts (LRs) and non-LRs in HEK-hD1R cells, but only in non-LRs in HEK-hD5R and hRPT cells. Long-term (hrs) fenoldopam stimulation increased PON2 protein in a time-dependent manner in HEK-hD5R, but not in HEK-hD1R cells. Because the effects of fenoldopam on non-LR and total PON2 expressions were similar in HEK-hD5R and hRPT cells, additional studies were performed to determine the relationship between D5R and PON2. Renal PON2 protein was decreased in D5(-/-) mice. In hRPT cells, silencing D5R decreased PON2 expression and increased ROS production. CONCLUSIONS We conclude that D1-like receptors inhibit ROS production by altering PON2 distribution in membrane microdomains in the short-term, and by increasing PON2 expression in the long-term.
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Affiliation(s)
- S Yang
- Department of Cardiology, Daping Hospital, The Third Military Medical University , Chongqing , P. R. China
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Li Y, Wang N, Chen C, He D, Yang J, Zeng C. Inhibitory effect of D3dopamine receptor on migration of vascular smooth muscle cells induced by synergistic effect of angiotensin II and aldosterone. Clin Exp Hypertens 2014; 37:288-93. [DOI: 10.3109/10641963.2014.960971] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Arystarkhova E, Ralph DL, Liu YB, Bouley R, McDonough AA, Sweadner KJ. Paradoxical activation of the sodium chloride cotransporter (NCC) without hypertension in kidney deficient in a regulatory subunit of Na,K-ATPase, FXYD2. Physiol Rep 2014; 2:2/12/e12226. [PMID: 25472608 PMCID: PMC4332208 DOI: 10.14814/phy2.12226] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Na,K‐ATPase generates the driving force for sodium reabsorption in the kidney.
Na,K‐ATPase functional properties are regulated by small proteins belonging to the FXYD
family. In kidney FXYD2 is the most abundant: it is an inhibitory subunit expressed in almost every
nephron segment. Its absence should increase sodium pump activity and promote Na+
retention, however, no obvious renal phenotype was detected in mice with global deletion of FXYD2
(Arystarkhova et al. 2013). Here, increased total cortical Na,K‐ATPase activity was
documented in the Fxyd2−/− mouse, without increased
α1β1 subunit expression. We tested the hypothesis
that adaptations occur in distal convoluted tubule (DCT), a major site of sodium adjustments.
Na,K‐ATPase immunoreactivity in DCT was unchanged, and there was no DCT hypoplasia. There was
a marked activation of thiazide‐sensitive sodium chloride cotransporter (NCC; Slc12a3) in
DCT, predicted to increase Na+ reabsorption in this segment. Specifically, NCC
total increased 30% and NCC phosphorylated at T53 and S71, associated with activation,
increased 4‐6 fold. The phosphorylation of the closely related thick ascending limb (TAL)
apical NKCC2 (Slc12a1) increased at least twofold. Abundance of the total and cleaved (activated)
forms of ENaC α‐subunit was not different between genotypes.
Nonetheless, no elevation of blood pressure was evident despite the fact that NCC and NKCC2 are in
states permissive for Na+ retention. Activation of NCC and NKCC2 may reflect an
intracellular linkage to elevated Na,K‐ATPase activity or a compensatory response to
Na+ loss proximal to the TAL and DCT. We discovered a substantial activation of renal NCC cotransporter in mice genetically depleted
for the regulatory inhibitory subunit of Na,K‐ATPase, FXYD2. Surprisingly, no significant
changes in urine output as well as elevation of blood pressure were detected suggesting compensatory
adaptation elsewhere in nephron
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Affiliation(s)
- Elena Arystarkhova
- Laboratory of Membrane Biology, Massachusetts General Hospital, Boston, Massachusetts
| | - Donna L Ralph
- Department of Cell and Neurobiology, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Yi Bessie Liu
- Laboratory of Membrane Biology, Massachusetts General Hospital, Boston, Massachusetts
| | - Richard Bouley
- MGH Center for Systems Biology, Program in Membrane Biology, Massachusetts General Hospital, Boston, Massachusetts
| | - Alicia A McDonough
- Department of Cell and Neurobiology, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Kathleen J Sweadner
- Laboratory of Membrane Biology, Massachusetts General Hospital, Boston, Massachusetts
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Ennis RC, Asico LD, Armando I, Yang J, Feranil JB, Jurgens JA, Escano CS, Yu P, Wang X, Sibley DR, Jose PA, Villar VAM. Dopamine D₁-like receptors regulate the α₁A-adrenergic receptor in human renal proximal tubule cells and D₁-like dopamine receptor knockout mice. Am J Physiol Renal Physiol 2014; 307:F1238-48. [PMID: 25339698 DOI: 10.1152/ajprenal.00119.2014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The homeostatic control of blood pressure hinges upon the delicate balance between prohypertensinogenic and antihypertensinogenic systems. D₁-like dopamine receptors [dopamine D₁ and D₅ receptors (D₁Rs and D₅Rs, respectively)] and the α₁A-adrenergic receptor (α₁A-AR) are expressed in the renal proximal tubule and engender opposing effects on Na(+) transport, i.e., natriuresis (via D₁Rs and D5Rs) or antinatriuresis (via α₁A-ARs). We tested the hypothesis that the D₁R/D₅R regulates the α₁A-AR. D₁-like dopamine receptors coimmunoprecipitated, colocalized, and cofractionated with α₁A-ARs in lipid rafts in immortalized human renal proximal tubule cells. Long-term treatment with the D₁R/D₅R agonist fenoldopam resulted in decreased D₁R and D₅R expression but increased α₁A-AR abundance in the plasma membrane. Short-term fenoldopam treatment stimulated the translocation of Na(+)-K(+)-ATPase from the plasma membrane to the cytosol that was partially reversed by an α₁A-AR agonist, which by itself induced Na(+)-K(+)-ATPase translocation from the cytosol to the plasma membrane. The α₁A-AR-specific agonist A610603 also minimized the ability of fenoldopam to inhibit Na(+)-K(+)-ATPase activity. To determine the interaction among D₁Rs, D₅Rs, and α₁A-ARs in vivo, we used phenylephrine and A610603 to decrease Na(+) excretion in several D1-like dopamine receptor knockout mouse strains. Phenylephrine and A61603 treatment resulted in a partial reduction of urinary Na(+) excretion in wild-type mice and its abolition in D1R knockout, D₅R knockout, and D₁R-D₅R double-knockout mice. Our results demonstrate the ability of the D₁-like dopamine receptors to regulate the expression and activity of α₁A-AR. Elucidating the intricacies of the interaction among these receptors is crucial for a better understanding of the crosstalk between anti- and pro-hypertensive systems.
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Affiliation(s)
- Riley Charles Ennis
- Thomas Jefferson High School for Science and Technology, Alexandria, Virgina
| | - Laureano D Asico
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Ines Armando
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Jian Yang
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Jun B Feranil
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Julie A Jurgens
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Crisanto S Escano
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Peiying Yu
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Xiaoyan Wang
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - David R Sibley
- Molecular Neuropharmacology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland
| | - Pedro A Jose
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland; Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Van Anthony M Villar
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland;
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Atrial natriuretic peptide and renal dopaminergic system: a positive friendly relationship? BIOMED RESEARCH INTERNATIONAL 2014; 2014:710781. [PMID: 25013796 PMCID: PMC4075025 DOI: 10.1155/2014/710781] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 05/12/2014] [Accepted: 05/12/2014] [Indexed: 01/11/2023]
Abstract
Sodium metabolism by the kidney is accomplished by an intricate interaction between signals from extrarenal and intrarenal sources and between antinatriuretic and natriuretic factors. Renal dopamine plays a central role in this interactive network. The natriuretic hormones, such as the atrial natriuretic peptide, mediate some of their effects by affecting the renal dopaminergic system. Renal dopaminergic tonus can be modulated at different steps of dopamine metabolism (synthesis, uptake, release, catabolism, and receptor sensitization) which can be regulated by the atrial natriuretic peptide. At tubular level, dopamine and atrial natriuretic peptide act together in a concerted manner to promote sodium excretion, especially through the overinhibition of Na+, K+-ATPase activity. In this way, different pathological scenarios where renal sodium excretion is dysregulated, as in nephrotic syndrome or hypertension, are associated with impaired action of renal dopamine and/or atrial natriuretic peptide, or as a result of impaired interaction between these two natriuretic systems. The aim of this review is to update and comment on the most recent evidences demonstrating how the renal dopaminergic system interacts with atrial natriuretic peptide to control renal physiology and blood pressure through different regulatory pathways.
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Granda ML, Schroeder FA, Borra RHJ, Schauer N, Aisaborhale E, Guimaraes AR, Hooker JM. First D1-like receptor PET imaging of the rat and primate kidney: implications for human disease monitoring. Am J Physiol Renal Physiol 2014; 307:F116-21. [PMID: 24808534 DOI: 10.1152/ajprenal.00111.2014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The intrarenal dopamine system is important for signaling and natriuresis, and significant dysfunction is associated with hypertension and kidney disease in ex vivo studies. Dopamine receptors also modulate and are modulated by the renin-angiotensin-aldosterone system. Here, we show the first in vivo measurement of D1-like receptors in the renal cortex of Sprague-Dawley rat and Papio anubis baboon using [(11)C]NNC 112, a positron emission tomography radioligand for D1-like receptors. In addition, we show a D1-like binding potential response to angiotensin II blockade in rats using losartan. Demonstration of self-saturable binding in the rat as well as specific and saturable binding in Papio anubis validate the use of [(11)C]NNC 112 in the first in vivo measurement of renal dopamine D1-like receptors. Furthermore, [(11)C]NNC 112 is a radioligand tool already validated for use in probing human central nervous system (CNS) D1-like receptors. Our work demonstrates specific and saturable non-CNS binding in higher animals and the ability to quantify physiological response to drug treatment and provides a clear path to extend use of [(11)C]NNC 112 to study renal dopamine in humans.
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Affiliation(s)
- Michael L Granda
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts; and Eastern Virginia Medical School, Norfolk, Virginia
| | - Frederick A Schroeder
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts; and
| | - Ronald H J Borra
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts; and
| | - Nathan Schauer
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts; and
| | - Ehimen Aisaborhale
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts; and
| | - Alexander R Guimaraes
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts; and
| | - Jacob M Hooker
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts; and
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Gildea JJ, Shah IT, Van Sciver RE, Israel JA, Enzensperger C, McGrath HE, Jose PA, Felder RA. The cooperative roles of the dopamine receptors, D1R and D5R, on the regulation of renal sodium transport. Kidney Int 2014; 86:118-26. [PMID: 24552847 PMCID: PMC4077925 DOI: 10.1038/ki.2014.5] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 11/27/2013] [Accepted: 12/12/2013] [Indexed: 02/07/2023]
Abstract
Determining the individual roles of the two dopamine D1-like receptors (D1R and D5R) on sodium transport in the human renal proximal tubule has been complicated by their structural and functional similarity. Here we used a novel D5R-selective antagonist (LE-PM436) and D1R or D5R-specific gene silencing to determine second messenger coupling pathways and heterologous receptor interaction between the two receptors. D1R and D5R co-localized in renal proximal tubule cells and physically interact, as determined by co-immunoprecipitation and FRET microscopy. Stimulation of renal proximal tubule cells with fenoldopam (D1R/D5R agonist) led to both adenylyl cyclase and phospholipase C (PLC) activation using real-time FRET biosensors ICUE3 and CYPHR, respectively. Fenoldopam increased cAMP accumulation and PLC activity and inhibited both NHE3 and NaKATPase activities. LE-PM436 and D5R siRNA blocked the fenoldopam-stimulated PLC pathway but not cAMP accumulation, while D1R siRNA blocked both fenoldopam-stimulated cAMP accumulation and PLC signaling. Either D1R or D5R siRNA, or LE-PM436 blocked the fenoldopam dependent inhibition of sodium transport. Further studies using the cAMP-selective D1R/D5R agonist SKF83822 and PLC-selective D1R/D5R agonist SKF83959 confirmed the cooperative influence of the two pathways on sodium transport. Thus, D1R and D5R interact in the inhibition of NHE3 and NaKATPase activity, the D1R primarily by cAMP, while the D1R/D5R heteromer modulates the D1R effect through a PLC pathway.
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Affiliation(s)
- John J Gildea
- The University of Virginia Health System, Department of Pathology, Charlottesville, Virginia, USA
| | - Ishan T Shah
- The University of Virginia Health System, Department of Pathology, Charlottesville, Virginia, USA
| | - Robert E Van Sciver
- The University of Virginia Health System, Department of Pathology, Charlottesville, Virginia, USA
| | - Jonathan A Israel
- The University of Virginia Health System, Department of Pathology, Charlottesville, Virginia, USA
| | - Christoph Enzensperger
- Institut für Pharmazie, Lehrstuhl für Pharmazeutische/Medizinische Chemie, Friedrich-Schiller-Universität Jena, Jena, Germany
| | - Helen E McGrath
- The University of Virginia Health System, Department of Pathology, Charlottesville, Virginia, USA
| | - Pedro A Jose
- University of Maryland School of Medicine, Departments of Medicine and Physiology, Baltimore, Maryland, USA
| | - Robin A Felder
- The University of Virginia Health System, Department of Pathology, Charlottesville, Virginia, USA
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Niewinski P, Tubek S, Banasiak W, Paton JFR, Ponikowski P. Consequences of peripheral chemoreflex inhibition with low-dose dopamine in humans. J Physiol 2014; 592:1295-308. [PMID: 24396060 DOI: 10.1113/jphysiol.2013.266858] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Low-dose dopamine inhibits peripheral chemoreceptors and attenuates the hypoxic ventilatory response (HVR) in humans. However, it is unknown: (1) whether it also modulates the haemodynamic reactions to acute hypoxia, (2) whether it also modulates cardiac baroreflex sensitivity (BRS) and (3) if there is any effect of dopamine withdrawal. We performed a double-blind, placebo-controlled study on 11 healthy male volunteers. At sea level over 2 days every subject was administered low-dose dopamine (2 μg kg(-1) min(-1)) or saline infusion, during which we assessed both ventilatory and haemodynamic responses to acute hypoxia. Separately, we evaluated effects of initiation and withdrawal of each infusion and BRS. The initiation of dopamine infusion did not affect minute ventilation (MV) or mean blood pressure (MAP), but increased both heart rate (HR) and cardiac output. Concomitantly, it decreased systemic vascular resistance. Dopamine blunted the ventilatory, MAP and HR reactions (hypertension, tachycardia) to acute hypoxia. Dopamine attenuated cardiac BRS to falling blood pressure. Dopamine withdrawal evoked an increase in MV. The magnitude of the increment in MV due to dopamine withdrawal correlated with the size of the HVR and depended on the duration of dopamine administration. The ventilatory reaction to dopamine withdrawal constitutes a novel index of peripheral chemoreceptor function.
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Affiliation(s)
- Piotr Niewinski
- Department of Cardiology, Centre for Heart Diseases, 4 Military Hospital, Ul. Weigla 5, 50-981, Wroclaw, Poland.
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Jiang X, Konkalmatt P, Yang Y, Gildea J, Jones JE, Cuevas S, Felder RA, Jose PA, Armando I. Single-nucleotide polymorphisms of the dopamine D2 receptor increase inflammation and fibrosis in human renal proximal tubule cells. Hypertension 2013; 63:e74-80. [PMID: 24379187 DOI: 10.1161/hypertensionaha.113.02569] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The dopamine D2 receptor (D2R) negatively regulates inflammation in mouse renal proximal tubule cells (RPTCs), and lack or downregulation of the receptor in mice increases the vulnerability to renal inflammation independent of blood pressure. Some common single-nucleotide polymorphisms (SNPs; rs6276, rs6277, and rs1800497) in the human DRD2 gene are associated with decreased D2R expression and function, as well as high blood pressure. We tested the hypothesis that human RPTCs (hRPTCs) expressing these SNPs have increased expression of inflammatory and injury markers. We studied immortalized hRPTCs carrying D2R SNPs and compared them with cells carrying no D2R SNPs. RPTCs with D2R SNPs had decreased D2R expression and function. The expressions of the proinflammatory tumor necrosis factor-α and the profibrotic transforming growth factor-β1 and its signaling targets Smad3 and Snail1 were increased in hRPTC with D2R SNPs. These cells also showed induction of epithelial mesenchymal transition and production of extracellular matrix proteins, assessed by increased vimentin, fibronectin 1, and collagen I a1. To test the specificity of these D2R SNP effects, hRPTC with D2R SNPs were transfected with a plasmid encoding wild-type DRD2. The expression of D2R was increased and that of transforming growth factor-β1, Smad3, Snail1, vimentin, fibronectin 1, and collagen I a1 was decreased in hRPTC with D2R SNPs transfected with wild-type DRD2 compared with hRPTC-D2R SNP transfected with empty vector. These data support the hypothesis that D2R function has protective effects in hRPTCs and suggest that carriers of these SNPs may be prone to chronic renal disease and high blood pressure.
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Affiliation(s)
- Xiaoliang Jiang
- University of Maryland School of Medicine, Department of Medicine, Division of Nephrology, 20 Penn St- HSFII Suite S003C, Baltimore, MD 21201.
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Zhang MZ, Wang Y, Yao B, Gewin L, Wei S, Capdevila JH, Harris RC. Role of epoxyeicosatrienoic acids (EETs) in mediation of dopamine's effects in the kidney. Am J Physiol Renal Physiol 2013; 305:F1680-6. [PMID: 24154693 DOI: 10.1152/ajprenal.00409.2013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
We have recently demonstrated that intrarenal dopamine plays an important role in preventing the development of systemic hypertension. Similarly, renal cytochrome P-450 (CYP)-epoxygenase-derived arachidonic acid metabolites, epoxyeicosatrienoic acids (EETs), also are antihypertensive through inhibiting sodium reabsorption and vasodilation. The potential interaction between renal dopamine and epoxygenase systems was investigated. Catechol-O-methyl-transferase (COMT)(-/-) mice with increased intrarenal dopamine levels and proximal tubule deletion of aromatic amino acid decarboxylase (ptAADC(-/-)) mice with renal dopamine deficiency were treated with a low-salt diet or high-salt diet for 2 wk. Wild-type or Cyp2c44(-/-) mice were treated with gludopa, which selectively increased renal dopamine levels. In low salt-treated mice, urinary EET levels were related to renal dopamine levels, being highest in COMT(-/-) mice and lowest in ptAADC(-/-) mice. In high salt-treated mice, total EET and individual EET levels in both the kidney and urine were also highest in COMT(-/-) mice and lowest in ptAADC(-/-) mice. Selective increases in renal dopamine in response to gludopa administration led to marked increases in both total and all individual EET levels in the kidney without any changes in blood levels. qRT-PCR and immunoblotting indicated that gludopa increased renal Cyp2c44 mRNA and protein levels. Gludopa induced marked increases in urine volume and urinary sodium excretion in wild-type mice. In contrast, gludopa did not induce significant increases in urine volume or urinary sodium excretion in Cyp2c44(-/-) mice. These studies demonstrate that renal EET levels are maintained by intrarenal dopamine, and Cyp2c44-derived EETs play an important role in intrarenal dopamine-induced natriuresis and diuresis.
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Affiliation(s)
- Ming-Zhi Zhang
- Div. of Nephrology, C3121 MCN, Vanderbilt Univ. School of Medicine and Nashville Veterans Affairs Hospital, Nashville, TN 37232.
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75
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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: 5.2] [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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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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Weinman EJ, Lederer ED. NHERF-1 and the regulation of renal phosphate reabsoption: a tale of three hormones. Am J Physiol Renal Physiol 2012; 303:F321-7. [PMID: 22535796 DOI: 10.1152/ajprenal.00093.2012] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The renal excretion of inorganic phosphate is regulated in large measure by three hormones, namely, parathyroid hormone, dopamine, and fibroblast growth factor-23. Recent experiments have indicated that the major sodium-dependent phosphate transporter in the renal proximal tubule, Npt2a, binds to the adaptor protein sodium-hydrogen exchanger regulatory factor-1 (NHERF-1) and in the absence of NHERF-1, the inhibitory effect of these three hormones is absent. From these observations, a new model for the hormonal regulation of renal phosphate transport was developed. The downstream signaling pathways of these hormones results in the phosphorylation of the PDZ 1 domain of NHERF-1 and the dissociation of Npt2a/NHERF-1 complexes. In turn, this dissociation facilitates the endocytosis of Npt2a with a subsequent decrease in the apical membrane abundance of the transporter and a decrease in phosphate reabsorption. The current review outlines the experimental observations supporting the operation of this unique regulatory system.
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Affiliation(s)
- Edward J Weinman
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA.
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