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Zatz R, De Nucci G. Endothelium-Derived Dopamine and 6-Nitrodopamine in the Cardiovascular System. Physiology (Bethesda) 2024; 39:44-59. [PMID: 37874898 PMCID: PMC11283902 DOI: 10.1152/physiol.00020.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 10/09/2023] [Accepted: 10/20/2023] [Indexed: 10/26/2023] Open
Abstract
The review deals with the release of endothelium-derived dopamine and 6-nitrodopamine (6-ND) and its effects on isolated vascular tissues and isolated hearts. Basal release of both dopamine and 6-ND is present in human isolated umbilical cord vessels, human popliteal vessels, nonhuman primate vessels, and reptilia aortas. The 6-ND basal release was significantly reduced when the tissues were treated with Nω-nitro-l-arginine methyl ester and virtually abolished when the endothelium was mechanically removed. 6-Nitrodopamine is a potent vasodilator, and the mechanism of action responsible for this effect is the antagonism of dopamine D2-like receptors. As a vasodilator, 6-ND constitutes a novel mechanism by which nitric oxide modulates vascular tone. The basal release of 6-ND was substantially decreased in endothelial nitric oxide synthase knockout (eNOS-/-) mice and not altered in neuronal nitric oxide synthase knockout (nNOS-/-) mice, indicating a nonneurogenic source for 6-ND in the heart. Indeed, in rat isolated right atrium, the release of 6-ND was not affected when the atria were treated with tetrodotoxin. In the rat isolated right atrium, 6-ND is the most potent endogenous positive chronotropic agent, and in Langendorff's heart preparation, it is the most potent endogenous positive inotropic agent. The positive chronotropic and inotropic effects of 6-ND are antagonized by β1-adrenoceptor antagonists at concentrations that do not affect the effects induced by noradrenaline, adrenaline, and dopamine, indicating that blockade of the 6-ND receptor is the major modulator of heart chronotropism and inotropism. The review proposes that endothelium-derived catecholamines may constitute a major mechanism for control of vascular tone and heart functions, in contrast to the overrated role attributed to the autonomic nervous system.
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Affiliation(s)
- Roberto Zatz
- Renal Division, Department of Clinical Medicine, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | - Gilberto De Nucci
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo (ICB-USP), São Paulo, Brazil
- Department of Pharmacology, Faculty of Medicine, São Leopoldo Mandic, Campinas, São Paulo, Brazil
- Department of Pharmacology, Faculty of Medicine, Metropolitan University of Santos, Santos, São Paulo, Brazil
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2
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Drury ER, Wu J, Gigliotti JC, Le TH. Sex differences in blood pressure regulation and hypertension: renal, hemodynamic, and hormonal mechanisms. Physiol Rev 2024; 104:199-251. [PMID: 37477622 PMCID: PMC11281816 DOI: 10.1152/physrev.00041.2022] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 06/06/2023] [Accepted: 07/16/2023] [Indexed: 07/22/2023] Open
Abstract
The teleology of sex differences has been argued since at least as early as Aristotle's controversial Generation of Animals more than 300 years BC, which reflects the sex bias of the time to contemporary readers. Although the question "why are the sexes different" remains a topic of debate in the present day in metaphysics, the recent emphasis on sex comparison in research studies has led to the question "how are the sexes different" being addressed in health science through numerous observational studies in both health and disease susceptibility, including blood pressure regulation and hypertension. These efforts have resulted in better understanding of differences in males and females at the molecular level that partially explain their differences in vascular function and renal sodium handling and hence blood pressure and the consequential cardiovascular and kidney disease risks in hypertension. This review focuses on clinical studies comparing differences between men and women in blood pressure over the life span and response to dietary sodium and highlights experimental models investigating sexual dimorphism in the renin-angiotensin-aldosterone, vascular, sympathetic nervous, and immune systems, endothelin, the major renal sodium transporters/exchangers/channels, and the impact of sex hormones on these systems in blood pressure homeostasis. Understanding the mechanisms governing sex differences in blood pressure regulation could guide novel therapeutic approaches in a sex-specific manner to lower cardiovascular risks in hypertension and advance personalized medicine.
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Affiliation(s)
- Erika R Drury
- Division of Nephrology, Department of Medicine, University of Rochester Medical Center, Rochester, New York, United States
| | - Jing Wu
- Division of Nephrology, Department of Medicine, University of Rochester Medical Center, Rochester, New York, United States
- Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, New York, United States
| | - Joseph C Gigliotti
- Department of Integrative Physiology and Pharmacology, Liberty University College of Osteopathic Medicine, Lynchburg, Virginia, United States
| | - Thu H Le
- Division of Nephrology, Department of Medicine, University of Rochester Medical Center, Rochester, New York, United States
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3
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Renal sympathetic activity: A key modulator of pressure natriuresis in hypertension. Biochem Pharmacol 2023; 208:115386. [PMID: 36535529 DOI: 10.1016/j.bcp.2022.115386] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 12/11/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022]
Abstract
Hypertension is a complex disorder ensuing necessarily from alterations in the pressure-natriuresis relationship, the main determinant of long-term control of blood pressure. This mechanism sets natriuresis to the level of blood pressure, so that increasing pressure translates into higher osmotically driven diuresis to reduce volemia and control blood pressure. External factors affecting the renal handling of sodium regulate the pressure-natriuresis relationship so that more or less natriuresis is attained for each level of blood pressure. Hypertension can thus only develop following primary alterations in the pressure to natriuresis balance, or by abnormal activity of the regulation network. On the other hand, increased sympathetic tone is a very frequent finding in most forms of hypertension, long regarded as a key element in the pathophysiological scenario. In this article, we critically analyze the interplay of the renal component of the sympathetic nervous system and the pressure-natriuresis mechanism in the development of hypertension. A special focus is placed on discussing recent findings supporting a role of baroreceptors as a component, along with the afference of reno-renal reflex, of the input to the nucleus tractus solitarius, the central structure governing the long-term regulation of renal sympathetic efferent tone.
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Liu XY, Li J, Zhang Y, Fan L, Xia Y, Wu Y, Chen J, Zhao X, Gao Q, Xu B, Nie C, Li Z, Tong A, Wang W, Cai J. Kidney microbiota dysbiosis contributes to the development of hypertension. Gut Microbes 2022; 14:2143220. [PMID: 36369946 PMCID: PMC9662196 DOI: 10.1080/19490976.2022.2143220] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Gut microbiota dysbiosis promotes metabolic syndromes (e.g., hypertension); however, the patterns that drive hypertensive pathology and could be targeted for therapeutic intervention are unclear. We hypothesized that gut microbes might translocate to the kidney to trigger hypertension. We aimed to uncover their method of colonization, and thereby how to maintain blood pressure homeostasis. Using combined approaches based on fluorescence in situ hybridization (FISH) and immunofluorescence staining, electron microscopy analysis, bacterial cultures, species identification, and RNA-sequencing-based meta-transcriptomics, we first demonstrated the presence of bacteria within the kidney of spontaneously hypertensive rats (SHRs) and its normotensive counterpart, Wistar-Kyoto rats (WKYs), and patients with hypertension. Translocated renal bacteria were coated with secretory IgA (sIgA) or remained dormant in the L-form. Klebsiella pneumoniae (K.pn) was identified in the kidneys of germ-free (GF) mice following intestinal transplantation, which suggested an influx of gut bacteria into the kidneys. Renal bacterial taxa and their function are associated with hypertension. Hypertensive hosts showed increased richness in the pathobionts of their kidneys, which were partly derived from the gastrointestinal tract. We also demonstrated the indispensable role of bacterial IgA proteases in the translocation of live microbes. Furthermore, Tartary buckwheat dietary intervention reduced blood pressure and modulated the core renal flora-host ecosystem to near-normal states. Taken together, the unique patterns of viable and dormant bacteria in the kidney provide insight into the pathogenesis of non-communicable chronic diseases and cardiometabolic diseases (e.g., hypertension), and may lead to potential novel microbiota-targeted dietary therapies.
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Affiliation(s)
- Xin-Yu Liu
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, China,CONTACT Xin-Yu Liu State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Jing Li
- Hypertension Center, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China,Heart Center & Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Yamei Zhang
- Clinical Genetics Laboratory, Affiliated Hospital &Clinical Medical College of Chengdu University, Chengdu, P.R. China,School of Food and Biological Engineering, Chengdu University, Chengdu, China
| | - Luyun Fan
- Hypertension Center, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yanli Xia
- Clinical Genetics Laboratory, Affiliated Hospital &Clinical Medical College of Chengdu University, Chengdu, P.R. China,School of Food and Biological Engineering, Chengdu University, Chengdu, China
| | - Yongyang Wu
- Department of Urology, Affiliated Sanming First Hospital, Fujian Medical University, Sanming, China
| | - Junru Chen
- Reproductive and Genetic Hospital of CITIC‐Xiangya, Changsha, China
| | - Xinyu Zhao
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Qiannan Gao
- Hypertension Center, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Bing Xu
- Department of Proctology, University of Chinese Academy of Sciences-Shenzhen Hospital (Guang Ming), Shenzhen, China
| | - Chunlai Nie
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Zhengyu Li
- Department of Obstetrics and Gynecology, Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Aiping Tong
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Wenjie Wang
- Hypertension Center, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jun Cai
- Hypertension Center, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China,Jun Cai Hypertension Center, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, China
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5
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Wang ZB, Jiang SL, Liu SB, Peng JB, Hu S, Wang X, Zhuo W, Liu T, Guo JW, Zhou HH, Yang ZQ, Mao XY, Liu ZQ. Metabolomics of Artichoke Bud Extract in Spontaneously Hypertensive Rats. ACS OMEGA 2021; 6:18610-18622. [PMID: 34337201 PMCID: PMC8319930 DOI: 10.1021/acsomega.1c01135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 07/05/2021] [Indexed: 05/10/2023]
Abstract
Hypertension adversely affects the quality of life in humans across modern society. Studies have attributed increased reactive oxygen species production to the pathophysiology of hypertension. So far, a specific drug to control the disease perfectly has not been developed. However, artichoke, an edible vegetable, plays an essential role in treating many diseases due to its potent antioxidant activities. The objective of this study is to evaluate the effect of artichoke bud extract (ABE) on heart tissue metabolomics of hypertensive rats. Spontaneously hypertensive rats and Wistar-Kyoto (WKY) rats were divided into six groups, then exposed to different doses comprising ABE, Enalapril Maleate, or 1% carboxylmethyl cellulose for 4 weeks. Their blood pressures were recorded at 0, 2, 3, and 4 weeks after the start of the test period. Thereafter, all rats were anesthetized, and blood was collected from their cardiac apexes. Then, we measured the levels for 15 kinds of serum biochemical parameters. An established orthogonal partial least square-discriminant analysis model completed the metabolomic analysis. Hypertensive rats in the ABE group exhibited well-controlled blood pressure, relative to those in the model group. Specifically, artichoke significantly lowered serum levels for total protein (TP), albumin (ALB), and uric acid (UA) in the hypertensive rats. This effect involved the action of eight metabolites, including guanine, 1-methylnicotinamide, p-aminobenzoic acid, NAD, NADH, uridine 5'-monophosphate, adenosine monophosphate, and methylmalonic acid. Collectively, these findings suggest that ABE may play a role in affecting oxidative stress and purine, nicotinate, and nicotinamide metabolism.
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Affiliation(s)
- Zhi-Bin Wang
- Department
of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics,
and National Clinical Research Center for Geriatric Disorders, Xiangya
Hospital, Central South University, Changsha 410008, P. R. China
- Institute
of Clinical Pharmacology, Engineering Research Center for Applied
Technology of Pharmacogenomics of Ministry of Education, Central South University, Changsha 410078, P. R. China
| | - Shi-Long Jiang
- Department
of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics,
and National Clinical Research Center for Geriatric Disorders, Xiangya
Hospital, Central South University, Changsha 410008, P. R. China
- Institute
of Clinical Pharmacology, Engineering Research Center for Applied
Technology of Pharmacogenomics of Ministry of Education, Central South University, Changsha 410078, P. R. China
| | - Shao-Bo Liu
- Department
of Pharmacy, Xiangya Hospital, Central South
University, Changsha 410008, P. R. China
| | - Jing-Bo Peng
- Department
of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics,
and National Clinical Research Center for Geriatric Disorders, Xiangya
Hospital, Central South University, Changsha 410008, P. R. China
- Institute
of Clinical Pharmacology, Engineering Research Center for Applied
Technology of Pharmacogenomics of Ministry of Education, Central South University, Changsha 410078, P. R. China
| | - Shuo Hu
- Department
of Nuclear Medicine and Key Laboratory of Biological Nanotechnology
of National Health Commission, Xiangya Hospital, Central South University, Changsha 410008, P. R. China
| | - Xu Wang
- Department
of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics,
and National Clinical Research Center for Geriatric Disorders, Xiangya
Hospital, Central South University, Changsha 410008, P. R. China
- Institute
of Clinical Pharmacology, Engineering Research Center for Applied
Technology of Pharmacogenomics of Ministry of Education, Central South University, Changsha 410078, P. R. China
| | - Wei Zhuo
- Department
of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics,
and National Clinical Research Center for Geriatric Disorders, Xiangya
Hospital, Central South University, Changsha 410008, P. R. China
- Institute
of Clinical Pharmacology, Engineering Research Center for Applied
Technology of Pharmacogenomics of Ministry of Education, Central South University, Changsha 410078, P. R. China
| | - Tong Liu
- Department
of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics,
and National Clinical Research Center for Geriatric Disorders, Xiangya
Hospital, Central South University, Changsha 410008, P. R. China
- Institute
of Clinical Pharmacology, Engineering Research Center for Applied
Technology of Pharmacogenomics of Ministry of Education, Central South University, Changsha 410078, P. R. China
| | - Ji-Wei Guo
- Department
of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics,
and National Clinical Research Center for Geriatric Disorders, Xiangya
Hospital, Central South University, Changsha 410008, P. R. China
- Institute
of Clinical Pharmacology, Engineering Research Center for Applied
Technology of Pharmacogenomics of Ministry of Education, Central South University, Changsha 410078, P. R. China
| | - Hong-Hao Zhou
- Department
of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics,
and National Clinical Research Center for Geriatric Disorders, Xiangya
Hospital, Central South University, Changsha 410008, P. R. China
- Institute
of Clinical Pharmacology, Engineering Research Center for Applied
Technology of Pharmacogenomics of Ministry of Education, Central South University, Changsha 410078, P. R. China
| | - Zhi-Quan Yang
- Department
of Neurosurgery, Xiangya Hospital, Central
South University, Changsha 410008, P. R. China
- . Phone: +86 731 89753845. Fax: +86 731 82354476
| | - Xiao-Yuan Mao
- Department
of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics,
and National Clinical Research Center for Geriatric Disorders, Xiangya
Hospital, Central South University, Changsha 410008, P. R. China
- Institute
of Clinical Pharmacology, Engineering Research Center for Applied
Technology of Pharmacogenomics of Ministry of Education, Central South University, Changsha 410078, P. R. China
| | - Zhao-Qian Liu
- Department
of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics,
and National Clinical Research Center for Geriatric Disorders, Xiangya
Hospital, Central South University, Changsha 410008, P. R. China
- Institute
of Clinical Pharmacology, Engineering Research Center for Applied
Technology of Pharmacogenomics of Ministry of Education, Central South University, Changsha 410078, P. R. China
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6
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Giani JF, Veiras LC, Shen JZY, Bernstein EA, Cao D, Okwan-Duodu D, Khan Z, Gonzalez-Villalobos RA, Bernstein KE. Novel roles of the renal angiotensin-converting enzyme. Mol Cell Endocrinol 2021; 529:111257. [PMID: 33781839 PMCID: PMC8127398 DOI: 10.1016/j.mce.2021.111257] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 02/03/2021] [Accepted: 03/20/2021] [Indexed: 12/14/2022]
Abstract
The observation that all components of the renin angiotensin system (RAS) are expressed in the kidney and the fact that intratubular angiotensin (Ang) II levels greatly exceed the plasma concentration suggest that the synthesis of renal Ang II occurs independently of the circulating RAS. One of the main components of this so-called intrarenal RAS is angiotensin-converting enzyme (ACE). Although the role of ACE in renal disease is demonstrated by the therapeutic effectiveness of ACE inhibitors in treating several conditions, the exact contribution of intrarenal versus systemic ACE in renal disease remains unknown. Using genetically modified mouse models, our group demonstrated that renal ACE plays a key role in the development of several forms of hypertension. Specifically, although ACE is expressed in different cell types within the kidney, its expression in renal proximal tubular cells is essential for the development of high blood pressure. Besides hypertension, ACE is involved in several other renal diseases such as diabetic kidney disease, or acute kidney injury even when blood pressure is normal. In addition, studies suggest that ACE might mediate at least part of its effect through mechanisms that are independent of the Ang I conversion into Ang II and involve other substrates such as N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP), Ang-(1-7), and bradykinin, among others. In this review, we summarize the recent advances in understanding the contribution of intrarenal ACE to different pathological conditions and provide insight into the many roles of ACE besides the well-known synthesis of Ang II.
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Affiliation(s)
- Jorge F Giani
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
| | - Luciana C Veiras
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Justin Z Y Shen
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Ellen A Bernstein
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - DuoYao Cao
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Derick Okwan-Duodu
- Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Zakir Khan
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | | | - Kenneth E Bernstein
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
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Mabillard H, Sayer JA. The Molecular Genetics of Gordon Syndrome. Genes (Basel) 2019; 10:genes10120986. [PMID: 31795491 PMCID: PMC6947027 DOI: 10.3390/genes10120986] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 11/22/2019] [Accepted: 11/25/2019] [Indexed: 12/12/2022] Open
Abstract
Gordon syndrome is a rare inherited monogenic form of hypertension, which is associated with hyperkalaemia and metabolic acidosis. Since the recognition of this predominantly autosomal dominant condition in the 1960s, the study of families with Gordon syndrome has revealed four genes WNK1, WNK4, KLHL3, and CUL3 to be implicated in its pathogenesis after a phenotype–genotype correlation was realised. The encoded proteins Kelch-like 3 and Cullin 3 interact to form a ring-like complex to ubiquitinate WNK-kinase 4, which, in normal circumstances, interacts with the sodium chloride co-symporter (NCC), the epithelial sodium channel (ENaC), and the renal outer medullary potassium channel (ROMK) in an inhibitory manner to maintain normokalaemia and normotension. WNK-kinase 1 has an inhibitory action on WNK-kinase 4. Mutations in WNK1, WNK4, KLHL3, and CUL3 all result in the accumulation of WNK-kinase 4 and subsequent hypertension, hyperkalaemia, and metabolic acidosis. This review explains the clinical aspects, disease mechanisms, and molecular genetics of Gordon syndrome.
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Affiliation(s)
- Holly Mabillard
- Renal Services, The Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne NE7 7DN, UK;
| | - John A. Sayer
- Renal Services, The Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne NE7 7DN, UK;
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Institute of Genetic Medicine, Newcastle University, International Centre for Life, Central Parkway, Newcastle upon Tyne NE1 3BZ, UK
- NIHR Newcastle Biomedical Research Centre, Newcastle University, Newcastle upon Tyne NE4 5PL, UK
- Correspondence: ; Tel.: +44-191-2418608
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Sethna CB, Kee D, Casado P, Murphy M, Palmer LS, Ghorayeb SR, Morganstern B. Renal sonographic changes in heterogeneity index and echogenicity in children with hypertension: a novel assessment. ACTA ACUST UNITED AC 2018; 12:e77-e83. [PMID: 30502313 DOI: 10.1016/j.jash.2018.11.002] [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: 08/13/2018] [Revised: 10/18/2018] [Accepted: 11/09/2018] [Indexed: 11/17/2022]
Abstract
The kidneys are thought to contribute to the pathogenesis of primary hypertension, but hypertension is also known to cause target organ damage in the kidney. Noninvasive methods to capture possible changes in the kidney related to hypertension are limited. A new program that has been used to quantify the heterogeneity and percent echogenicity in renal ultrasound images was implemented to assess patients with hypertension. Children and adolescents <21 years with primary hypertension diagnosed by ambulatory blood pressure monitoring were compared with normotensive age- and sex-matched controls. Renal ultrasound images were evaluated by a technique that measured pixels of gray-scale images and transformed them into a binary map, which was converted to a heterogeneity index (HI) and percent echogenicity score. This study included 99 children with hypertension and 99 control subjects. Body mass index (BMI) was greater in the hypertension group. Average HI for hypertension was significantly higher than in controls (1.37 ± 0.19 vs. 1.2 ± 0.23, P = .001), while echogenicity scores were not different (26.6 ± 8.9 vs. 25.9 ± 10, P = .8). In regression analysis adjusting for BMI z-score and race, hypertension was associated with greater HI compared with controls (β = 0.11, 95% confidence interval 0.03-0.18, P = .005). In a model adjusted for age, sex, and BMI z-score in the hypertension group only, no ambulatory blood pressure monitoring measures were associated with HI or echogenicity scores (P > .05).HI was significantly greater in the hypertension group compared with normotensive controls. HI may be a novel method to detect changes in the kidney related to hypertension.
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Affiliation(s)
- Christine B Sethna
- Division of Pediatric Nephrology, Cohen Children's Medical Center, New Hyde Park, NY, USA; Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA; Feinstein Institute for Medical Research, Manhasset, NY, USA.
| | - Dustin Kee
- Division of Pediatric Nephrology, Cohen Children's Medical Center, New Hyde Park, NY, USA
| | - Pablo Casado
- Ultrasound Research Lab, DeMatteis School of Engineering and Applied Sciences, Hofstra University, Hempstead, NY, USA
| | - Megan Murphy
- Ultrasound Research Lab, DeMatteis School of Engineering and Applied Sciences, Hofstra University, Hempstead, NY, USA
| | - Lane S Palmer
- Division of Pediatric Urology, Cohen Children's Medical Center, New Hyde Park, NY, USA; Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
| | - Sleiman R Ghorayeb
- Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA; Feinstein Institute for Medical Research, Manhasset, NY, USA; Ultrasound Research Lab, DeMatteis School of Engineering and Applied Sciences, Hofstra University, Hempstead, NY, USA
| | - Bradley Morganstern
- Division of Pediatric Urology, Cohen Children's Medical Center, New Hyde Park, NY, USA
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9
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Blagonravov ML, Medvedeva EV, Bryk AA, Goryachev VA, Azova MM, Velichko EV. Specific Features of Electrolyte Excretion at the Early Stages of Arterial Hypertension in SHR Rats. Bull Exp Biol Med 2017; 164:15-17. [PMID: 29119397 DOI: 10.1007/s10517-017-3915-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Indexed: 11/28/2022]
Abstract
Daytime and nighttime systolic and diastolic BP was recorded in 23-week-old SHR and Wistar rats by telemetric monitoring. Urine concentrations of sodium, potassium, and calcium were determined in SHR rats during of light (07.00-19.00 h) and dark hours (19.00-07.00 h) at the age of 18, 19, 20, 21, 22, and 23 week; 23-week-old Wistar rats were used as the control. At early stages of the experiment, urine sodium concentration was elevated in SHR rats both at daytime and at night. Thereafter, this value declined and by 22-23 week was significantly lower than in normotensive Wistar rats, but only during daytime. Daytime potassium concentration significantly surpassed the control level during weeks 18-19 of the experiment, but later, a tendency to a decrease in this parameter was observed. Daytime calcium content in SHR rats did not significantly differ from the control throughout the experiment. At night, this value exceeded the control level by more than 2 times during weeks 18-19, but then returned to the level observed in normotensive animals.
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Affiliation(s)
- M L Blagonravov
- V. A. Frolov Department of General Pathology and Pathological Physiology, Moscow, Russia.
| | - E V Medvedeva
- V. A. Frolov Department of General Pathology and Pathological Physiology, Moscow, Russia
| | - A A Bryk
- V. A. Frolov Department of General Pathology and Pathological Physiology, Moscow, Russia
| | - V A Goryachev
- V. A. Frolov Department of General Pathology and Pathological Physiology, Moscow, Russia
| | - M M Azova
- Department of Biology and General Genetics, Medical Institute, Peoples' Friendship University of Russia, Moscow, Russia
| | - E V Velichko
- V. A. Frolov Department of General Pathology and Pathological Physiology, Moscow, Russia
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10
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Affiliation(s)
- John E Hall
- From the Department of Physiology and Biophysics, Mississippi Center for Obesity Research, University of Mississippi Medical Center, Jackson.
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11
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Chen D, Stegbauer J, Sparks MA, Kohan D, Griffiths R, Herrera M, Gurley SB, Coffman TM. Impact of Angiotensin Type 1A Receptors in Principal Cells of the Collecting Duct on Blood Pressure and Hypertension. Hypertension 2016; 67:1291-7. [PMID: 27141055 DOI: 10.1161/hypertensionaha.115.06987] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 03/16/2016] [Indexed: 01/09/2023]
Abstract
The main actions of the renin-angiotensin system to control blood pressure (BP) are mediated by the angiotensin type 1 receptors (AT1Rs). The major murine AT1R isoform, AT1AR, is expressed throughout the nephron, including the collecting duct in both principal and intercalated cells. Principal cells play the major role in sodium and water reabsorption. Although aldosterone is considered to be the dominant regulator of sodium reabsorption by principal cells, recent studies suggest a role for direct actions of AT1R. To specifically examine the contributions of AT1AR in principal cells to BP regulation and the development of hypertension in vivo, we generated inbred 129/SvEv mice with deletion of AT1AR from principal cells (PCKO). At baseline, we found that BPs measured by radiotelemetry were similar between PCKOs and controls. During 1-week of low-salt diet (<0.02% NaCl), BPs fell significantly (P<0.05) and to a similar extent in both groups. On a high-salt (6% NaCl) diet, BP increased but was not different between groups. During the initial phase of angiotensin II-dependent hypertension, there was a modest but significant attenuation of hypertension in PCKOs (163±6 mm Hg) compared with controls (178±2 mm Hg; P<0.05) that was associated with enhanced natriuresis and decreased alpha epithelial sodium channel activation in the medulla of PCKOs. However, from day 9 onward, BPs were indistinguishable between groups. Although effects of AT1AR on baseline BP and adaptation to changes in dietary salt are negligible, our studies suggest that direct actions of AT1AR contribute to the initiation of hypertension and epithelial sodium channel activation.
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Affiliation(s)
- Daian Chen
- From the Division of Nephrology, Department of Medicine, Duke University, and Durham VA Medical Centers, NC (D.C., M.A.S., R.G., M.H., S.B.G., T.M.C.); Department of Nephrology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany (J.S.); School of Medicine, University of Utah Health Sciences Center, Salt Lake City (D.K.); and Cardiovascular and Metabolic Disorders Research Program, Duke-NUS Graduate Medical School, Singapore, Singapore (T.M.C.)
| | - Johannes Stegbauer
- From the Division of Nephrology, Department of Medicine, Duke University, and Durham VA Medical Centers, NC (D.C., M.A.S., R.G., M.H., S.B.G., T.M.C.); Department of Nephrology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany (J.S.); School of Medicine, University of Utah Health Sciences Center, Salt Lake City (D.K.); and Cardiovascular and Metabolic Disorders Research Program, Duke-NUS Graduate Medical School, Singapore, Singapore (T.M.C.)
| | - Matthew A Sparks
- From the Division of Nephrology, Department of Medicine, Duke University, and Durham VA Medical Centers, NC (D.C., M.A.S., R.G., M.H., S.B.G., T.M.C.); Department of Nephrology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany (J.S.); School of Medicine, University of Utah Health Sciences Center, Salt Lake City (D.K.); and Cardiovascular and Metabolic Disorders Research Program, Duke-NUS Graduate Medical School, Singapore, Singapore (T.M.C.)
| | - Donald Kohan
- From the Division of Nephrology, Department of Medicine, Duke University, and Durham VA Medical Centers, NC (D.C., M.A.S., R.G., M.H., S.B.G., T.M.C.); Department of Nephrology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany (J.S.); School of Medicine, University of Utah Health Sciences Center, Salt Lake City (D.K.); and Cardiovascular and Metabolic Disorders Research Program, Duke-NUS Graduate Medical School, Singapore, Singapore (T.M.C.)
| | - Robert Griffiths
- From the Division of Nephrology, Department of Medicine, Duke University, and Durham VA Medical Centers, NC (D.C., M.A.S., R.G., M.H., S.B.G., T.M.C.); Department of Nephrology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany (J.S.); School of Medicine, University of Utah Health Sciences Center, Salt Lake City (D.K.); and Cardiovascular and Metabolic Disorders Research Program, Duke-NUS Graduate Medical School, Singapore, Singapore (T.M.C.)
| | - Marcela Herrera
- From the Division of Nephrology, Department of Medicine, Duke University, and Durham VA Medical Centers, NC (D.C., M.A.S., R.G., M.H., S.B.G., T.M.C.); Department of Nephrology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany (J.S.); School of Medicine, University of Utah Health Sciences Center, Salt Lake City (D.K.); and Cardiovascular and Metabolic Disorders Research Program, Duke-NUS Graduate Medical School, Singapore, Singapore (T.M.C.)
| | - Susan B Gurley
- From the Division of Nephrology, Department of Medicine, Duke University, and Durham VA Medical Centers, NC (D.C., M.A.S., R.G., M.H., S.B.G., T.M.C.); Department of Nephrology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany (J.S.); School of Medicine, University of Utah Health Sciences Center, Salt Lake City (D.K.); and Cardiovascular and Metabolic Disorders Research Program, Duke-NUS Graduate Medical School, Singapore, Singapore (T.M.C.)
| | - Thomas M Coffman
- From the Division of Nephrology, Department of Medicine, Duke University, and Durham VA Medical Centers, NC (D.C., M.A.S., R.G., M.H., S.B.G., T.M.C.); Department of Nephrology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany (J.S.); School of Medicine, University of Utah Health Sciences Center, Salt Lake City (D.K.); and Cardiovascular and Metabolic Disorders Research Program, Duke-NUS Graduate Medical School, Singapore, Singapore (T.M.C.).
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12
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Pathophysiology and treatment of resistant hypertension: the role of aldosterone and amiloride-sensitive sodium channels. Semin Nephrol 2015; 34:532-9. [PMID: 25416662 DOI: 10.1016/j.semnephrol.2014.08.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Resistant hypertension is a clinically distinct subgroup of hypertension defined by the failure to achieve blood pressure control on optimal dosing of at least 3 antihypertensive medications of different classes, including a diuretic. The pathophysiology of hypertension can be attributed to aldosterone excess in more than 20% of patients with resistant hypertension. Existing dogma attributes the increase in blood pressure seen with increases in aldosterone to its antinatriuretic effects in the distal nephron. However, emerging research, which has identified and has begun to define the function of amiloride-sensitive sodium channels and mineralocorticoid receptors in the systemic vasculature, challenges impaired natriuresis as the sole cause of aldosterone-mediated resistant hypertension. This review integrates these findings to better define the role of the vasculature and aldosterone in the pathophysiology of resistant hypertension. In addition, a brief guide to the treatment of resistant hypertension is presented.
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13
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Abstract
Intrarenal autoregulatory mechanisms maintain renal blood flow (RBF) and glomerular filtration rate (GFR) independent of renal perfusion pressure (RPP) over a defined range (80-180 mmHg). Such autoregulation is mediated largely by the myogenic and the macula densa-tubuloglomerular feedback (MD-TGF) responses that regulate preglomerular vasomotor tone primarily of the afferent arteriole. Differences in response times allow separation of these mechanisms in the time and frequency domains. Mechanotransduction initiating the myogenic response requires a sensing mechanism activated by stretch of vascular smooth muscle cells (VSMCs) and coupled to intracellular signaling pathways eliciting plasma membrane depolarization and a rise in cytosolic free calcium concentration ([Ca(2+)]i). Proposed mechanosensors include epithelial sodium channels (ENaC), integrins, and/or transient receptor potential (TRP) channels. Increased [Ca(2+)]i occurs predominantly by Ca(2+) influx through L-type voltage-operated Ca(2+) channels (VOCC). Increased [Ca(2+)]i activates inositol trisphosphate receptors (IP3R) and ryanodine receptors (RyR) to mobilize Ca(2+) from sarcoplasmic reticular stores. Myogenic vasoconstriction is sustained by increased Ca(2+) sensitivity, mediated by protein kinase C and Rho/Rho-kinase that favors a positive balance between myosin light-chain kinase and phosphatase. Increased RPP activates MD-TGF by transducing a signal of epithelial MD salt reabsorption to adjust afferent arteriolar vasoconstriction. A combination of vascular and tubular mechanisms, novel to the kidney, provides for high autoregulatory efficiency that maintains RBF and GFR, stabilizes sodium excretion, and buffers transmission of RPP to sensitive glomerular capillaries, thereby protecting against hypertensive barotrauma. A unique aspect of the myogenic response in the renal vasculature is modulation of its strength and speed by the MD-TGF and by a connecting tubule glomerular feedback (CT-GF) mechanism. Reactive oxygen species and nitric oxide are modulators of myogenic and MD-TGF mechanisms. Attenuated renal autoregulation contributes to renal damage in many, but not all, models of renal, diabetic, and hypertensive diseases. This review provides a summary of our current knowledge regarding underlying mechanisms enabling renal autoregulation in health and disease and methods used for its study.
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Affiliation(s)
- Mattias Carlström
- Department of Medicine, Division of Nephrology and Hypertension and Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, District of Columbia; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and Department of Cell Biology and Physiology, UNC Kidney Center, and McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Christopher S Wilcox
- Department of Medicine, Division of Nephrology and Hypertension and Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, District of Columbia; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and Department of Cell Biology and Physiology, UNC Kidney Center, and McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - William J Arendshorst
- Department of Medicine, Division of Nephrology and Hypertension and Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, District of Columbia; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and Department of Cell Biology and Physiology, UNC Kidney Center, and McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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14
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Rho kinase inhibition mitigates sunitinib-induced rise in arterial pressure and renal vascular resistance but not increased renal sodium reabsorption. J Hypertens 2014; 32:2199-210; discussion 2110. [DOI: 10.1097/hjh.0000000000000326] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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15
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Ivy JR, Bailey MA. Pressure natriuresis and the renal control of arterial blood pressure. J Physiol 2014; 592:3955-67. [PMID: 25107929 DOI: 10.1113/jphysiol.2014.271676] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The regulation of extracellular fluid volume by renal sodium excretion lies at the centre of blood pressure homeostasis. Renal perfusion pressure can directly regulate sodium reabsorption in the proximal tubule. This acute pressure natriuresis response is a uniquely powerful means of stabilizing long-term blood pressure around a set point. By logical extension, deviation from the set point can only be sustained if the pressure natriuresis mechanism is impaired, suggesting that hypertension is caused or sustained by a defect in the relationship between renal perfusion pressure and sodium excretion. Here we describe the role of pressure natriuresis in blood pressure control and outline the cascade of biophysical and paracrine events in the renal medulla that integrate the vascular and tubular response to altered perfusion pressure. Pressure natriuresis is impaired in hypertension and mechanistic insight into dysfunction comes from genetic analysis of blood pressure disorders. Transplantation studies in rats show that blood pressure is determined by the genotype of the kidney and Mendelian hypertension indicates that the distal nephron influences the overall natriuretic efficiency. These approaches and the outcomes of genome-wide-association studies broaden our view of blood pressure control, suggesting that renal sympathetic nerve activity and local inflammation can impair pressure natriuresis to cause hypertension. Understanding how these systems interact is necessary to tackle the global burden of hypertension.
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Affiliation(s)
- Jessica R Ivy
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Matthew A Bailey
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
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16
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Graham LA, Padmanabhan S, Fraser NJ, Kumar S, Bates JM, Raffi HS, Welsh P, Beattie W, Hao S, Leh S, Hultstrom M, Ferreri NR, Dominiczak AF, Graham D, McBride MW. Validation of Uromodulin as a Candidate Gene for Human Essential Hypertension. Hypertension 2014; 63:551-8. [DOI: 10.1161/hypertensionaha.113.01423] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A recent genome-wide association study identified a locus on chromosome 16 in the promoter region of the uromodulin (
UMOD
) gene that is associated with hypertension. Here, we examined the hypertension signal with functional studies in Umod knockout (KO) mice. Systolic blood pressure was significantly lower in KO versus wild-type (WT) mice under basal conditions (KO: 116.6±0.3 mm Hg versus WT: 136.2±0.4 mm Hg;
P
<0.0001). Administration of 2% NaCl did not alter systolic blood pressure in KO mice, whereas it increased in WT mice by ≈33%,
P
<0.001. The average 24-hour urinary sodium excretion in the KO was greater than that of WT mice (
P
<0.001). Chronic renal function curves demonstrate a leftward shift in KO mice, suggesting that the relationship between UMOD and blood pressure is affected by sodium. Creatinine clearance was increased during salt loading with 2% NaCl in the KO mice, leading to augmented filtered Na
+
excretion and further Na
+
loss. The difference in sodium uptake that exists between WT and KO strains was explored at the molecular level. Urinary tumor necrosis factor-α levels were significantly higher in KO mice compared with WT mice (
P
<0.0001). Stimulation of primary thick ascending limb of the loop of Henle cells with exogenous tumor necrosis factor-α caused a reduction in NKCC2A expression (
P
<0.001) with a concurrent rise in the levels of UMOD mRNA (
P
<0.001). Collectively, we demonstrate that UMOD regulates sodium uptake in the thick ascending limb of the loop of Henle by modulating the effect of tumor necrosis factor-α on NKCC2A expression, making UMOD an important determinant of blood pressure control.
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Affiliation(s)
- Lesley A. Graham
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Sandosh Padmanabhan
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Niall J. Fraser
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Satish Kumar
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - James M. Bates
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Hajamohideen S. Raffi
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Paul Welsh
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Wendy Beattie
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Shoujin Hao
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Sabine Leh
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Michael Hultstrom
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Nicholas R. Ferreri
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Anna F. Dominiczak
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Delyth Graham
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
| | - Martin W. McBride
- From the Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom (L.A.G., S.P., N.J.F., P.W., W.B., A.F.D., D.G., M.W.M.); Department of Medicine, University of Oklahoma Health Sciences Centre and Veterans Affairs Medical Center, Oklahoma City (S.K., J.M.B., H.S.R.); Department of Pharmacology, New York Medical College, Valhalla (S.H., N.R.F.); Department of Pathology, Haukeland University Hospital, Bergen, Norway
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17
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Franceschini N, Le TH. Genetics of hypertension: discoveries from the bench to human populations. Am J Physiol Renal Physiol 2014; 306:F1-F11. [PMID: 24133117 PMCID: PMC3921821 DOI: 10.1152/ajprenal.00334.2013] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 10/11/2013] [Indexed: 12/20/2022] Open
Abstract
Hypertension is a complex trait that is influenced by both heritable and environmental factors. The search for genes accounting for the susceptibility to hypertension has driven parallel efforts in human research and in research using experimental animals in controlled environmental settings. Evidence from rodent models of genetic hypertension and human Mendelian forms of hypertension and hypotension have yielded mechanistic insights into the pathways that are perturbed in blood pressure homeostasis, most of which converge at the level of renal sodium reabsorption. However, the bridging of evidence from these very diverse approaches to identify mechanisms underlying hypertension susceptibility and the translation of these findings to human populations and public health remain a challenge. Furthermore, findings from genome-wide association studies still require functional validation in experimental models. In this review, we highlight results and implications from key studies in experimental and clinical hypertension to date.
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18
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Rodríguez-Pérez A, López-Rodríguez J, Calvo-Turrubiartes M, Saavedra-Alanís V, Llamazares-Azuara L, Rodríguez-Martínez M. Partial baroreceptor dysfunction and low plasma nitric oxide bioavailability as determinants of salt-sensitive hypertension: a reverse translational rat study. Braz J Med Biol Res 2013; 46:868-880. [PMID: 24141614 PMCID: PMC3854306 DOI: 10.1590/1414-431x20132834] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Accepted: 07/17/2013] [Indexed: 11/26/2022] Open
Abstract
This study determined whether clinical salt-sensitive hypertension (cSSHT) results from the interaction between partial arterial baroreceptor impairment and a high-sodium (HNa) diet. In three series (S-I, S-II, S-III), mean arterial pressure (MAP) of conscious male Wistar ChR003 rats was measured once before (pdMAP) and twice after either sham (SHM) or bilateral aortic denervation (AD), following 7 days on a low-sodium (LNa) diet (LNaMAP) and then 21 days on a HNa diet (HNaMAP). The roles of plasma nitric oxide bioavailability (pNOB), renal medullary superoxide anion production (RMSAP), and mRNA expression of NAD(P)H oxidase and superoxide dismutase were also assessed. In SHM (n=11) and AD (n=15) groups of S-I, LNaMAP-pdMAP was 10.5±2.1 vs 23±2.1 mmHg (P<0.001), and the salt-sensitivity index (SSi; HNaMAP-LNaMAP) was 6.0±1.9 vs 12.7±1.9 mmHg (P=0.03), respectively. In the SHM group, all rats were normotensive, and 36% were salt sensitive (SSi≥10 mmHg), whereas in the AD group ∼50% showed cSSHT. A 45% reduction in pNOB (P≤0.004) was observed in both groups in dietary transit. RMSAP increased in the AD group on both diets but more so on the HNa diet (S-II, P<0.03) than on the LNa diet (S-III, P<0.04). MAP modeling in rats without a renal hypertensive genotype indicated that the AD*HNa diet interaction (P=0.008) increases the likelihood of developing cSSHT. Translationally, these findings help to explain why subjects with clinical salt-sensitive normotension may transition to cSSHT.
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Affiliation(s)
- A.S. Rodríguez-Pérez
- Integrative Physiology Laboratory, Department of Physiology and
Biophysics, San Luis Potosí, Mexico
| | - J.F. López-Rodríguez
- Integrative Physiology Laboratory, Department of Physiology and
Biophysics, San Luis Potosí, Mexico
| | - M.Z. Calvo-Turrubiartes
- Integrative Physiology Laboratory, Department of Physiology and
Biophysics, San Luis Potosí, Mexico
| | - V.M. Saavedra-Alanís
- Molecular Biology Laboratory, Department of Biochemistry, San
Luis Potosí, Mexico
| | - L. Llamazares-Azuara
- Autonomous University of San Luis Potosí, Renal Laboratory,
Faculty of Medicine, San Luis Potosí, Mexico
| | - M. Rodríguez-Martínez
- Integrative Physiology Laboratory, Department of Physiology and
Biophysics, San Luis Potosí, Mexico
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19
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Schlote J, Schröder A, Dahlmann A, Karpe B, Cordasic N, Daniel C, Hilgers KF, Titze J, Amann K, Benz K. Cardiovascular and renal effects of high salt diet in GDNF+/- mice with low nephron number. Kidney Blood Press Res 2013; 37:379-91. [PMID: 24247178 DOI: 10.1159/000355716] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2013] [Indexed: 11/19/2022] Open
Abstract
AIMS To test the suggested association of low nephron number and later development of renal and cardiovascular disease we investigated the effects of high sodium diet in heterozygous GDNF+/- mice. METHODS Aged wild type and GDNF+/- mice were grouped together according to high sodium (HS, 4%) or low sodium (LS, 0.03%) diet for 4 weeks. The heart, the aorta and the kidneys were processed for morphometric and stereological evaluations and TaqMan PCR. RESULTS On HS GDNF+/- mice showed significantly higher drinking volume and urine production than wt and mean arterial blood pressure tended to be higher. Heart weight was higher in GDNF+/- than in wt, but the difference was only significant for LS. HS significantly increased cardiac interstitial tissue in GDNF+/-, but not in wt. On LS GDNF+/- mice had significantly larger glomeruli than wt and HS led to an additional two fold increase of glomerular area compared to LS. On electron microscopy glomerular damage after HS was seen in GDNF+/-, but not in wt. Dietary salt intake modulated renal IL-10 gene expression in GDNF+/-. CONCLUSION In the setting of 30% lower nephron number HS diet favoured maladaptive changes of the kidney as well as of the cardiovascular system.
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Affiliation(s)
- Julia Schlote
- Department of Pathology, IZKF Nachwuchsgruppe, Department of Nephrology and Hypertension, Department of Pediatrics, University of Erlangen-Nürnberg, Germany
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Fox MOB, Gutiérrez EB. Role of the glomerular–tubular imbalance with tubular predominance in the arterial hypertension pathophysiology. Med Hypotheses 2013; 81:397-9. [DOI: 10.1016/j.mehy.2013.05.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Accepted: 05/21/2013] [Indexed: 10/26/2022]
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The Rho kinase inhibitor SAR407899 potently inhibits endothelin-1-induced constriction of renal resistance arteries. J Hypertens 2012; 30:980-9. [PMID: 22388233 DOI: 10.1097/hjh.0b013e328351d459] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Increased renal vascular resistance contributes to the pathogenesis of hypertension. The new Rho kinase (ROCK) inhibitor SAR407899 more potently lowers arterial pressure than the commercially available ROCK inhibitor Y27623. We tested whether ROCK inhibition more effectively reduced agonist-induced vasoconstriction in renal than in nonrenal resistance arteries and if SAR407899 more potently inhibits agonist-induced vasoconstriction than Y27632. METHODS The effects of the ROCK inhibitors on endothelin-1 (ET-1) induced vasoconstriction were investigated in isolated renal and coronary arteries from lean, normotensive Dark Agouti and obese, type 2 diabetic Zucker diabetic fatty (ZDF) rats as well as in isolated human resistance arteries from the kidney and thymus. Vascular ROCK mRNA abundance was studied by real-time PCR (RT-PCR). RESULTS ET-1-induced constriction depended more on ROCK in rat and human renal resistance arteries than in rat coronary or human thymic arteries, respectively. SAR407899 was more effective than Y27632 in reducing ET-1-induced vasoconstriction in ZDF rat renal resistance arteries. Maximum ET-1-induced vasoconstriction in SAR407899-treated and Y27632-treated human renal resistance arteries was 23 ± 5 and 48 ± 6% of control values, respectively. Transcripts of both ROCK isoforms were detected in rat and human renal resistance arteries. In human thymic arteries, only the ROCK2 transcript was found. CONCLUSION ET-1-induced vasoconstriction is more ROCK-dependent in renal than in nonrenal resistance arteries. SAR407899 causes a greater inhibition of ET-1-induced vasoconstriction in renal resistance arteries from ZDF rats and patients than Y27632. The greater efficacy in renal vessels may contribute to the higher antihypertensive potency of SAR407899 compared with Y27632.
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Northcott CA, Glenn JP, Shade RE, Kammerer CM, Hinojosa-Laborde C, Fink GD, Haywood JR, Cox LA. A custom rat and baboon hypertension gene array to compare experimental models. Exp Biol Med (Maywood) 2012; 237:99-110. [PMID: 22228705 DOI: 10.1258/ebm.2011.011188] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
One challenge in understanding the polygenic disease of hypertension is elucidating the genes involved and defining responses to environmental factors. Many studies focus on animal models of hypertension; however, this does not necessarily extrapolate to humans. Current technology and cost limitations are prohibitive in fully evaluating hypertension within humans. Thus, we have designed a single-array platform that allows direct comparison of genes relevant to hypertension in animal models and non-human primates/human hypertension. The custom array is targeted to 328 genes known to be potentially related to blood pressure control. Studies compared gene expression in the kidney from normotensive rats and baboons. We found 74 genes expressed in both the rat and baboon kidney, 41 genes expressed in the rat kidney that were not detected in the baboon kidney and 34 genes expressed in the baboon kidney that were not detected in the rat kidney. To begin the evaluation of the array in a pathological condition, kidney gene expression was compared between the salt-sensitive deoxycorticosterone acetate (DOCA) rat model of hypertension and sham animals. Gene expression in the renal cortex and medulla from hypertensive DOCA compared with sham rats revealed three genes differentially expressed in the renal cortex: annexin A1 (up-regulated; relative intensity: 1.316 ± 0.321 versus 2.312 ± 0.283), glutamate-cysteine ligase (down-regulated; relative intensity: 3.738 ± 0.174 versus 2.645 ± 0.364) and glutathione-S transferase (down-regulated; relative intensity: 5.572 ± 0.246 versus 4.215 ± 0.411) and 21 genes differentially expressed in the renal medulla. Interestingly, few genes were differentially expressed in the kidney in the DOCA-salt model of hypertension; this may suggest that the complexity of hypertension may be the result of only a few gene-by-environment responsive events.
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Affiliation(s)
- Carrie A Northcott
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA.
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Abstract
High blood pressure, or hypertension, is a very common disorder with a substantial impact on public health because of its associated complications. Despite the high prevalence of essential hypertension and years of research, the basic causes remain obscure. Here I review recent advances in understanding the pathophysiology of hypertension. I present a general overview of the field and, by necessity, use broad strokes to portray recent progress and place it in context. For this purpose, I use illustrative examples from the large number of important developments in hypertension research over the last five years. The intent of this review is to provide a sense of where the field is progressing, with an emphasis on work that sheds light on pathogenic mechanisms and that is therefore likely to inform new translational advances.
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Abstract
Kidney disease is commonly associated with hypertension in dogs, cats and other species. There are multiple mechanisms underlying the development of renal hypertension including sodium retention, activation of the renin-angiotensin system and sympathetic nerve stimulation. The relative importance of these and other mechanisms may vary both between species and according to the type of kidney disease that is present. Consideration of underlying disease mechanisms may aid in the rational choice of therapy in hypertensive patients.
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Affiliation(s)
- Harriet Syme
- Department of Veterinary Clinical Sciences, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK.
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Ritz E, Amann K, Koleganova N, Benz K. Prenatal programming-effects on blood pressure and renal function. Nat Rev Nephrol 2011; 7:137-44. [PMID: 21283139 DOI: 10.1038/nrneph.2011.1] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Impaired intrauterine nephrogenesis-most clearly illustrated by low nephron number-is frequently associated with low birthweight and has been recognized as a powerful risk factor for renal disease; it increases the risks of low glomerular filtration rate, of more rapid progression of primary kidney disease, and of increased incidence of chronic kidney disease or end-stage renal disease. Another important consequence of impaired nephrogenesis is hypertension, which further amplifies the risk of onset and progression of kidney disease. Hypertension is associated with low nephron numbers in white individuals, but the association is not universal and is not seen in individuals of African origin. The derangement of intrauterine kidney development is an example of a more general principle that illustrates the paradigm of plasticity during development-that is, that transcription of the genetic code is modified by epigenetic factors (as has increasingly been documented). This Review outlines the concept of prenatal programming and, in particular, describes its role in kidney disease and hypertension.
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Affiliation(s)
- Eberhard Ritz
- Division of Nephrology, Department of Internal Medicine, University of Heidelberg, Heidelberg 69100, Germany.
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Benz K, Campean V, Cordasic N, Karpe B, Neuhuber W, Mall G, Hartner A, Hilgers KF, Amann K. Early glomerular alterations in genetically determined low nephron number. Am J Physiol Renal Physiol 2011; 300:F521-30. [DOI: 10.1152/ajprenal.00490.2009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
An association between low nephron number and subsequent development of hypertension in later life has been demonstrated. The underlying pathomechanisms are unknown, but glomerular and postglomerular changes have been discussed. We investigated whether such changes are already present in prehypertensive “glial cell line-derived neurotrophic growth factor” heterozygous mice (GDNF+/−) with lower nephron number. Twenty-six-week-old mice [22 GDNF+/−, 29 C57B6 wild-type control (wt)] were used for in vivo experiments with intra-arterial and tail cuff blood pressure measurements. After perfusion fixation, kidneys were investigated with morphological, morphometric, stereological, and immunohistochemical techniques and TaqMan PCR analysis. As expected at this age, blood pressure was comparable between GDNF+/− and wt. Nephron number per kidney was significantly lower in GDNF+/− than in wt (−32.8%, P < 0.005), and mean glomerular volume was significantly higher (+49.5%, P < 0.001). Renal damage scores, glomerular and tubular proliferation, analysis of intrarenal arteries and peritubular capillaries, expression of relevant tubular transporter proteins, as well as gene expression of profibrotic, proinflammatory, or prohypertensive markers were not significantly different between GDNF+/− and wt. Compensatory glomerular hypertrophy in GDNF+/− was accompanied by higher numbers of endothelial and mesangial cells as well as PCNA-positive glomerular cells, whereas podocyte density was significantly reduced. Further electron microscopic analysis showed marked thickening of glomerular basement membrane. In conclusion, lower nephron number is associated with marked early glomerular structural changes, in particular lower capillary supply, reduced podocyte density, and thickened glomerular basement membrane, that may predispose to glomerular sclerosis.
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Affiliation(s)
| | | | | | | | | | - Gerhard Mall
- Department of Pathology, Hospital of Darmstadt, Darmstadt, Germany
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Motility of the ureter of the spontaneously hypertensive rat. Ir J Med Sci 2011; 180:489-95. [DOI: 10.1007/s11845-010-0592-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Accepted: 09/20/2010] [Indexed: 10/18/2022]
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Kobori H, Fu Q, Crowley SD, Gonzalez-Villalobos RA, Campos RR. Comments on Point:Counterpoint: The dominant contributor to systemic hypertension: Chronic activation of the sympathetic nervous system vs. Activation of the intrarenal renin-angiotensin system. Activated intrarenal renin-angiotensin system is correlated with high blood pressure in humans. J Appl Physiol (1985) 2010; 109:2003. [PMID: 21148352 PMCID: PMC3774210 DOI: 10.1152/japplphysiol.01160.2010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Hiroyuki Kobori
- Department of Medicine, Tulane University Health Sciences Center, LA, USA
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Glodny B, Nasseri P, Rehder P, Unterholzner V, Plaikner M, Koppelstätter C, Petersen J. Reduced glomerular filtration rate due to loss of nephron mass may be an independent risk factor for atherosclerosis. Nephrol Dial Transplant 2010; 26:1882-7. [PMID: 21068141 DOI: 10.1093/ndt/gfq678] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Whether living with reduced nephron mass (RNM) poses a risk to humans is the subject of ongoing controversy. The aim of this study was to discover whether or not RNMs are associated with greater atherosclerotic plaque burdens. METHODS Using the post-operative abdominal CT scans of 739 nephrectomized patients [NP; 315 women and 424 men; mean age 64.5 ± 15.0 years; observation period 4.9 ± 5.7 years (3675.9 patient-years)] and of an age- and a gender-matched control group, a retrospective observational and case-control study was conducted. The V600 calcium scoring method was used to determine the aortic calcium volume score (ACS) and thus the APB. RESULTS The ACS was 0.47 ± 0.77 mm(3) in the NPs compared with 0.41 ± 0.69 mm(3) in the control group (P <0.0001). The ACS and the glomerular filtration rate (GFR using the CKD-EPI formula) after nephrectomy correlated inversely (P = - 0.3652; P <0.0001), and the ACS and the time since nephrectomy correlated positively (P = 0.2919; P <0.0001). In linear regression models, age, time interval and GFR after nephrectomy proved to be independent factors of influence on ACS (P <0.05 each). Including the control group, age, GFR after nephrectomy and nephrectomy were independent factors of influence on the ACS. The factor GFR after nephrectomy explains ~ 10.7% in NPs, and 28% of the variance of the ACS in all patients. CONCLUSIONS The factors 'low GFR' and RNM are risk factors for greater atherosclerotic plaque burden. Patients with RNM should undergo regular control examinations to monitor arterial blood pressure and treat hypertension if it occurs.
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Affiliation(s)
- Bernhard Glodny
- Department of Radiology, Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck, Austria
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Amiloride lowers arterial pressure in cyp1a1ren-2 transgenic rats without affecting renal vascular function. J Hypertens 2010; 28:2267-77. [DOI: 10.1097/hjh.0b013e32833d77b4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Castrop H, Höcherl K, Kurtz A, Schweda F, Todorov V, Wagner C. Physiology of Kidney Renin. Physiol Rev 2010; 90:607-73. [PMID: 20393195 DOI: 10.1152/physrev.00011.2009] [Citation(s) in RCA: 189] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The protease renin is the key enzyme of the renin-angiotensin-aldosterone cascade, which is relevant under both physiological and pathophysiological settings. The kidney is the only organ capable of releasing enzymatically active renin. Although the characteristic juxtaglomerular position is the best known site of renin generation, renin-producing cells in the kidney can vary in number and localization. (Pro)renin gene transcription in these cells is controlled by a number of transcription factors, among which CREB is the best characterized. Pro-renin is stored in vesicles, activated to renin, and then released upon demand. The release of renin is under the control of the cAMP (stimulatory) and Ca2+(inhibitory) signaling pathways. Meanwhile, a great number of intrarenally generated or systemically acting factors have been identified that control the renin secretion directly at the level of renin-producing cells, by activating either of the signaling pathways mentioned above. The broad spectrum of biological actions of (pro)renin is mediated by receptors for (pro)renin, angiotensin II and angiotensin-( 1 – 7 ).
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Affiliation(s)
- Hayo Castrop
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Klaus Höcherl
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Armin Kurtz
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Frank Schweda
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Vladimir Todorov
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Charlotte Wagner
- Institute of Physiology, University of Regensburg, Regensburg, Germany
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Signaling mechanisms that link salt retention to hypertension: endogenous ouabain, the Na(+) pump, the Na(+)/Ca(2+) exchanger and TRPC proteins. Biochim Biophys Acta Mol Basis Dis 2010; 1802:1219-29. [PMID: 20211726 DOI: 10.1016/j.bbadis.2010.02.011] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 02/26/2010] [Accepted: 02/27/2010] [Indexed: 12/26/2022]
Abstract
Salt retention as a result of chronic, excessive dietary salt intake, is widely accepted as one of the most common causes of hypertension. In a small minority of cases, enhanced Na(+) reabsorption by the kidney can be traced to specific genetic defects of salt transport, or pathological conditions of the kidney, adrenal cortex, or pituitary. Far more frequently, however, salt retention may be the result of minor renal injury or small genetic variation in renal salt transport mechanisms. How salt retention actually leads to the increase in peripheral vascular resistance (the hallmark of hypertension) and the elevation of blood pressure remains an enigma. Here we review the evidence that endogenous ouabain (an adrenocortical hormone), arterial smooth muscle α2 Na(+) pumps, type-1 Na/Ca exchangers, and receptor- and store-operated Ca(2+) channels play key roles in the pathway that links salt to hypertension. We discuss cardenolide structure-function relationships in an effort to understand why prolonged administration of ouabain, but not digoxin, induces hypertension, and why digoxin is actually anti-hypertensive. Finally, we summarize recent observations which indicate that ouabain upregulates arterial myocyte Ca(2+) signaling mechanisms that promote vasoconstriction, while simultaneously downregulating endothelial vasodilator mechanisms. In sum, the reports reviewed here provide novel insight into the molecular mechanisms by which salt retention leads to hypertension.
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Schlüter T, Zimmermann U, Protzel C, Miehe B, Klebingat KJ, Rettig R, Grisk O. Intrarenal artery superoxide is mainly NADPH oxidase-derived and modulates endothelium-dependent dilation in elderly patients. Cardiovasc Res 2009; 85:814-24. [PMID: 19843513 DOI: 10.1093/cvr/cvp346] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
AIMS The present study was performed to investigate the contribution of NADPH oxidases (Nox) to superoxide formation in human renal proximal resistance arteries and to test whether superoxide formation contributes to acute vasoconstrictor responses and endothelium-dependent vasodilation in these vessels. METHODS AND RESULTS Arcuate and proximal interlobular artery segments were from patients who underwent nephrectomy because of a renal tumour. Vessels were dissected from tumour-free parts of the kidneys. Additional intrarenal arteries were obtained from rats. Superoxide formation was measured by lucigenin-enhanced chemiluminescence, expression of Nox isoforms was analysed by RT-PCR, and functional studies were performed by small vessel wire myography. Sixty per cent of superoxide formation in human arcuate and proximal interlobular arteries was due to Nox activity. mRNA expression analyses revealed the presence of Nox2 and Nox4 but not Nox1. Phenylephrine and endothelin-1 induced powerful concentration-dependent vasoconstrictions that were unaffected by superoxide scavengers. Vasopressin elicited small and variable vasoconstrictions with signs of tachyphylaxis. Endothelium-dependent vasodilation was blunted by tiron and Nomega-nitro-L-arginine methyl ester but not by superoxide dismutase or catalase. Exogenous hydrogen peroxide elicited vasoconstriction. CONCLUSION Nox activity is the major source of superoxide formation in renal proximal resistance arteries from elderly patients. Acute vasoconstrictor responses to alpha1-adrenoreceptor activation and to endothelin-1 do not depend on superoxide formation, while endothelium-dependent vasodilation in intrarenal arteries is reactive oxygen species-dependent.
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Affiliation(s)
- Torsten Schlüter
- Department of Physiology, University Clinics of Greifswald, Greifswald, Germany
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Barber Fox M, Barber Gutiérrez E, Fox Pascual M. Comportamiento del volumen sanguíneo corporal en ratas con hipertrofia tubular proximal. HIPERTENSION Y RIESGO VASCULAR 2009. [DOI: 10.1016/s1889-1837(09)71182-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Roysommuti S, Lerdweeraphon W, Malila P, Jirakulsomchok D, Wyss JM. Perinatal taurine alters arterial pressure control and renal function in adult offspring. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 643:145-56. [PMID: 19239145 DOI: 10.1007/978-0-387-75681-3_15] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The present study investigates the effect of perinatal taurine exposure on renal function in adult, female rats on a high sugar diet. Perinatal taurine depleted (TD), supplemented (TS) or untreated control (C) female offspring were fed normal rat chow and tap water (CW,TDW or TSW) or tap water with 5% glucose (CG, TDG or TSG) after weaning. At 7-8 weeks of age, renal function was studied in the conscious, restrained rats. Mean arterial pressure was significantly higher in TDW, TDG, and TSG rats. Plasma sodium concentration was significantly lower in all glucose treated animals, but the greatest decrease was in TDW rats. Basal renal blood flow was lowest in TSW and TSG, and the responses to a saline load were also lowest in those two groups. These changes were consistent with increased renal vascular resistance. The basal glomerular filtration rate was lowest in TSW, but the responses to a saline load were similar in all of the groups. Water excretion was lower in TSG and TSW, consistent with increased renal tubular water reabsorption. These data suggest that perinatal taurine exposure alters normal renal function and renal responses to dietary sugar in adult female offspring.
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Affiliation(s)
- Sanya Roysommuti
- Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand.
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Ziomber A, Machnik A, Dahlmann A, Dietsch P, Beck FX, Wagner H, Hilgers KF, Luft FC, Eckardt KU, Titze J. Sodium-, potassium-, chloride-, and bicarbonate-related effects on blood pressure and electrolyte homeostasis in deoxycorticosterone acetate-treated rats. Am J Physiol Renal Physiol 2008; 295:F1752-63. [PMID: 18842823 DOI: 10.1152/ajprenal.00531.2007] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Na(+) loading without Cl(-) fails to increase blood pressure in the DOCA model. We compared the changes in the total body (TB) effective Na(+), K(+), Cl(-), and water (TBW) content as well as in intracellular (ICV) or extracellular (ECV) volume in rats receiving DOCA-NaCl, DOCA-NaHCO(3), or DOCA-KHCO(3). We divided 42 male rats into 5 groups. Group 1 was untreated, group 2 received 1% NaCl, and groups 3, 4, and 5 were treated with DOCA and received 1% NaCl, 1.44% NaHCO(3), or 1.7% KHCO(3) to drink. We measured mean arterial blood pressure (MAP) directly after 3 wk. Tissue electrolyte and water content was measured by chemical analysis. Compared with control rats, DOCA-NaCl increased MAP while DOCA-NaHCO(3) and DOCA-KHCO(3) did not. DOCA-NaCl increased TBNa(+) 26% but only moderately increased TBW. DOCA-NaHCO(3) led to similar TBNa(+) excess, while TBW and ICV, but not ECV, were increased more than in DOCA-NaCl rats. DOCA-KHCO(3) did not affect TBNa(+) or volume. At a given TB(Na(+)+K(+)) and TBW, MAP in DOCA-NaCl rats was higher than in control, DOCA-NaHCO(3), and DOCA-KHCO(3) rats, indicating that hypertension in DOCA-NaCl rats was not dependent on TB(Na(+)+K(+)) and water mass balance. Skin volume retention was hypertonic compared with serum and paralleled hypertension in DOCA-NaCl rats. These rats had higher TB(Na(+)+K(+))-to-TBW ratio in accumulated fluid than DOCA-NaHCO(3) rats. DOCA-NaCl rats also had increased intracellular Cl(-) concentrations in skeletal muscle. We conclude that excessive cellular electrolyte redistribution and/or intracellular Na(+) or Cl(-) accumulation may play an important role in the pathogenesis of salt-sensitive hypertension.
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Affiliation(s)
- Agata Ziomber
- Department of Nephrology and Hypertension, Nikolaus-Fiebiger Center for Molecular Medicine, Glückstr. 6, 91054 Erlangen, Germany
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Affiliation(s)
- Thomas M Coffman
- Division of Nephrology, Department of Medicine, Duke University and Durham Veterans'Affairs Medical Centers, Durham, NC, USA.
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McCormick JA, Yang CL, Ellison DH. WNK kinases and renal sodium transport in health and disease: an integrated view. Hypertension 2008; 51:588-96. [PMID: 18212265 DOI: 10.1161/hypertensionaha.107.103788] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- James A McCormick
- Division of Nephrology and Hypertension and Heart Research Center, Department of Medicine, Oregon Health and Science University, Portland, OR 97239, USA
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Abstract
A low nephron number has been advocated to explain the association between intrauterine growth restriction (IUGR) and hypertension in later life. IUGR not only leads to a low birth weight but is also hypothesized to reprogram nephrogenesis, which results in a low nephron endowment. Several methods are used to estimate the total glomerular number, but only stereological techniques result in accurate (unbiased) and precise (reproducible) data. Several studies, both in humans and animal models that have used these methods indeed revealed that IUGR leads to a low nephron number. According to the hyperfiltration hypothesis, this reduction in renal mass is supposed to lead to glomerular hyperfiltration and hypertension in remnant nephrons with subsequent glomerular injury with proteinuria, systemic hypertension and glomerulosclerosis. Even though IUGR is associated with both a low nephron endowment and an increased risk of hypertension, only circumstantial evidence is available to support the hyperfiltration hypothesis after prenatal programming. A prerequisite for establishment of this association in long-term, prospective follow-up studies is the ability to estimate glomerular numbers in living human beings, for which a further advancement in radiological techniques is necessary. Only then can the association between nephron endowment and blood pressure in humans be studied more conclusively.
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Affiliation(s)
- M F Schreuder
- Department of Pediatric Nephrology, Erasmus MC - Sophia Children's Hospital, University Medical Center, Rotterdam, The Netherlands.
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40
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Abstract
The kidney could be the cause of essential hypertension which can also cause renal disease. High blood pressure is also very common in chronic kidney disease, and is moreover a well-known risk factor for a faster progression of kidney failure. Hypertension and kidneys are thus closely linked. Hypertension must be aggressively treated in patients suffering from chronic kidney disease, with a blood pressure goal of less than 130/80 mmHg, even lower than 125/75 mmHg when proteinuria is over 1g/day, using optimal and effective antihypertensive drugs. Among them, the blockers of the renin-angiotensin axis offer nephroprotective but also cardioprotective properties beyond their effect on blood pressure.
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Affiliation(s)
- J M Krzesinski
- Division of Nephrology/Transplantation, University of Liège, Sart Titman B35, Belgium.
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Abstract
A crosstransplantation study between genetically matched angiotensin AT1 receptor knockout and wild-type mice revealed that renal AT1 receptors are required for the development of angiotensin II-induced hypertension (). However, in this experimental setting, hypertension-related left ventricular hypertrophy seemed to depend on blood pressure elevation rather than on the expression of AT1 receptors in the heart.
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Affiliation(s)
- Ulrike Muscha Steckelings
- Center for Cardiovascular Research, Institute of Pharmacology, Charité-Universitätsmedizin Berlin, 10115 Berlin, Germany
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Crowley SD, Gurley SB, Coffman TM. AT1 Receptors and Control of Blood Pressure: The Kidney and More…. Trends Cardiovasc Med 2007; 17:30-4. [PMID: 17210476 DOI: 10.1016/j.tcm.2006.11.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Revised: 10/14/2006] [Accepted: 11/02/2006] [Indexed: 11/28/2022]
Abstract
The renin-angiotensin system (RAS) is a critical regulator of blood pressure and fluid homeostasis. The components of the RAS including renin, angiotensin-converting enzyme, and angiotensin receptors are expressed throughout the body in tissues that may impact blood pressure control. Blocking actions of individual components of the RAS including renin, angiotensin-converting enzyme, or the type 1 (AT(1)) receptor lowers blood pressure. Although it has been suggested that control of sodium excretion by the kidney is the dominant mechanism for blood pressure regulation by the RAS, pharmacologic antagonists or conventional gene-targeting experiments globally interrupt the RAS and cannot discriminate its actions in the kidney from other tissue compartments. Recent experiments with the use of kidney cross-transplantation and genetically engineered mice suggest independent and equivalent effects of angiotensin II acting via AT(1) receptors in the kidney and in extrarenal tissues to maintain the normal level of blood pressure. However, the nature and relative contributions of these actions may differ in hypertension.
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Affiliation(s)
- Steven D Crowley
- Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, Durham, NC 27710, USA
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Schreuder M, Delemarre-van de Waal H, van Wijk A. Consequences of Intrauterine Growth Restriction for the Kidney. Kidney Blood Press Res 2006; 29:108-25. [PMID: 16837795 DOI: 10.1159/000094538] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Low birth weight due to intrauterine growth restriction is associated with various diseases in adulthood, such as hypertension, cardiovascular disease, insulin resistance and end-stage renal disease. The purpose of this review is to describe the effects of intrauterine growth restriction on the kidney. Nephrogenesis requires a fine balance of many factors that can be disturbed by intrauterine growth restriction, leading to a low nephron endowment. The compensatory hyperfiltration in the remaining nephrons results in glomerular and systemic hypertension. Hyperfiltration is attributed to several factors, including the renin-angiotensin system (RAS), insulin-like growth factor (IGF-I) and nitric oxide. Data from human and animal studies are presented, and suggest a faltering IGF-I and an inhibited RAS in intrauterine growth restriction. Hyperfiltration makes the kidney more vulnerable during additional kidney disease, and is associated with glomerular damage and kidney failure in the long run. Animal studies have provided a possible therapy with blockage of the RAS at an early stage in order to prevent the compensatory glomerular hyperfiltration, but this is far from being applicable to humans. Research is needed to further unravel the effect of intrauterine growth restriction on the kidney.
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Affiliation(s)
- Michiel Schreuder
- Department of Pediatric Nephrology, VU University Medical Center, Amsterdam, The Netherlands.
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Blaustein MP, Zhang J, Chen L, Hamilton BP. How does salt retention raise blood pressure? Am J Physiol Regul Integr Comp Physiol 2006; 290:R514-23. [PMID: 16467498 DOI: 10.1152/ajpregu.00819.2005] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
A critical question in hypertension research is: How is long-term blood pressure controlled? Excessive NaCl ingestion or NaCl retention by the kidneys and the consequent tendency toward plasma volume expansion lead to hypertension. Nevertheless, the precise mechanisms linking salt to high blood pressure are unresolved. The discovery of endogenous ouabain, an adrenocortical hormone, provided an important clue. Ouabain, a selective Na+ pump inhibitor, has cardiotonic and vasotonic effects. Plasma endogenous ouabain levels are significantly elevated in approximately 40% of patients with essential hypertension and in animals with several forms of salt-dependent hypertension. Also, prolonged ouabain administration induces hypertension in rodents. Mice with mutant Na+ pumps or Na/Ca exchangers (NCX) and studies with a ouabain antagonist and an NCX blocker are revealing the missing molecular mechanisms. These data demonstrate that alpha2 Na+ pumps and NCX1 participate in long-term regulation of vascular tone and blood pressure. Pharmacological agents or mutations in the alpha2 Na+ pump that interfere with the action of ouabain on the pump, and reduced NCX1 expression or agents that block NCX all impede the development of salt-dependent or ouabain-induced hypertension. Conversely, nanomolar ouabain, reduced alpha2 Na+ pump expression, and smooth muscle-specific overexpression of NCX1 all induce hypertension. Furthermore, ouabain and reduced alpha2 Na+ pump expression increase myogenic tone in isolated mesenteric small arteries in vitro, thereby tying these effects directly to the elevation of blood pressure. Thus, endogenous ouabain, and vascular alpha2 Na+ pumps and NCX1, are critical links between salt and hypertension. New pharmacological agents that act on these molecular links have potential in the clinical management of hypertension.
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Affiliation(s)
- Mordecai P Blaustein
- Department of Physiology, University of Maryland School of Medicine, 655 W. Baltimore St., Baltimore, Maryland 21201, USA.
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Schlüter T, Grimm R, Steinbach A, Lorenz G, Rettig R, Grisk O. Neonatal sympathectomy reduces NADPH oxidase activity and vascular resistance in spontaneously hypertensive rat kidneys. Am J Physiol Regul Integr Comp Physiol 2006; 291:R391-9. [PMID: 16914424 DOI: 10.1152/ajpregu.00029.2006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Neonatal sympathectomy reduces arterial pressure in spontaneously hypertensive rats (SHR). In SHR transplanted with a kidney from sympathectomized SHR, arterial pressure was lower and less Na+ sensitive than in SHR transplanted with a kidney from hydralazine-treated SHR. This study was performed to identify underlying renal mechanisms. Tests for differential renal mRNA expression of nine a priori selected genes revealed robust differences for renal medullary expression of the NADPH oxidase subunit p47phox. Therefore, we investigated the effects of neonatal sympathectomy on renal mRNA expression of NADPH oxidase subunits, NADPH oxidase activity, and renal function. In 10-wk-old sympathectomized SHR fed a 0.6% NaCl diet, medullary p47phox and gp91phox expression was 40% less than in hydralazine-treated SHR. Also, after a 1.8% NaCl diet, medullary p47phox mRNA expression was lower in sympathectomized than in hydralazine-treated SHR. We found lower cortical (-30%, P<0.01) and medullary (-30%, P<0.05) NADPH oxidase activities in sympathectomized than in hydralazine-treated or untreated SHR. Glomerular filtration rate, renal blood flow, medullary blood flow, and fractional Na+ excretion in kidney grafts from sympathectomized and hydralazine-treated donors (n=8 per group) were similar at baseline and in response to a 20-mmHg rise in renal perfusion pressure. Renal vascular resistance was lower in kidneys from sympathectomized than hydralazine-treated donors (25+/-2 vs. 32+/-4 mmHg.min.ml-1, P<0.05). The results indicate that the sympathetic nervous system contributes to the level of renal NADPH oxidase activity and to perinatal programming of alterations in renal vascular function that lead to elevated renal vascular resistance in SHR.
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Affiliation(s)
- Torsten Schlüter
- Institute of Physiology, University of Greifswald, Greifswalder Strasse 11c, D17495 Karlsburg, Germany
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Brantsma AH, Bakker SJL, de Zeeuw D, de Jong PE, Gansevoort RT. Urinary Albumin Excretion as a Predictor of the Development of Hypertension in the General Population. J Am Soc Nephrol 2006; 17:331-5. [PMID: 16434504 DOI: 10.1681/asn.2005111153] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The hypothesis that high urinary albumin excretion (UAE; indicating mild renal damage) may precede development of hypertension was tested, and the relation among UAE, GFR, and development of hypertension was investigated. Data of 4635 patients of a prospective cohort study who participated in an extensive screening in 1997 to 1998 and 2001 to 2003 at our outpatient unit and were normotensive at baseline were used. Hypertension was defined according to the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure criteria, UAE was measured in two consecutive 24-h urine samples, and GFR was calculated with the modified Modification of Diet in Renal Disease formula. Mean follow-up was 4.3 yr. Baseline UAE was significantly associated with the risk for developing hypertension (odds ratio 2.29; 95% confidence interval 1.77 to 2.95 per 10-fold increase of UAE). This association was independent of potential confounders. An interaction between UAE and GFR was found (P = 0.030), indicating that with elevated UAE and lowered GFR, but still within the normal range, the risk for developing hypertension was highest. In conclusion, these findings support the hypothesis that mild renal damage may precede the development of hypertension.
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Affiliation(s)
- Auke H Brantsma
- Division of Nephrology, Department of Medicine, University Medical Center Groningen, PO Box 30.001, Groningen, 9700 RB The Netherlands
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