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Patel M, Harris N, Kasztan M, Hyndman K. Comprehensive analysis of the endothelin system in the kidneys of mice, rats, and humans. Biosci Rep 2024; 44:BSR20240768. [PMID: 38904098 PMCID: PMC11249498 DOI: 10.1042/bsr20240768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2024] [Revised: 06/20/2024] [Accepted: 06/20/2024] [Indexed: 06/22/2024] Open
Abstract
The intrarenal endothelin (ET) system is an established moderator of kidney physiology and mechanistic contributor to the pathophysiology and progression of chronic kidney disease in humans and rodents. The aim of the present study was to characterize ET system by combining single cell RNA sequencing (scRNA-seq) data with immunolocalization in human and rodent kidneys of both sexes. Using publicly available scRNA-seq data, we assessed sex and kidney disease status (human), age and sex (rats), and diurnal expression (mice) on the kidney ET system expression. In normal human biopsies of both sexes and in rodent kidney samples, the endothelin-converting enzyme-1 (ECE1) and ET-1 were prominent in the glomeruli and endothelium. These data agreed with the scRNA-seq data from these three species, with ECE1/Ece1 mRNA enriched in the endothelium. However, the EDN1/Edn1 gene (encodes ET-1) was rarely detected, even though it was immunolocalized within the kidneys, and plasma and urinary ET-1 excretion are easily measured. Within each species, there were some sex-specific differences. For example, in kidney biopsies from living donors, men had a greater glomerular endothelial cell endothelin receptor B (Ednrb) compared with women. In mice, females had greater kidney endothelial cell Ednrb than male mice. As commercially available antibodies did not work in all species, and RNA expression did not always correlate with protein levels, multiple approaches should be considered to maintain required rigor and reproducibility of the pre- and clinical studies evaluating the intrarenal ET system.
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Affiliation(s)
- Margi Patel
- Department of Medicine, Division of Nephrology, Section of Cardio-Renal Physiology and Medicine, University of Alabama at Birmingham, Birmingham, AL 35233, U.K
| | - Nicholas Harris
- Department of Medicine, Division of Nephrology, Section of Cardio-Renal Physiology and Medicine, University of Alabama at Birmingham, Birmingham, AL 35233, U.K
| | - Malgorzata Kasztan
- Department of Pediatrics, Division of Hematology-Oncology, Section of Cardio-Renal Physiology and Medicine, University of Alabama at Birmingham, Birmingham, AL 35233, U.K
| | - Kelly A. Hyndman
- Department of Medicine, Division of Nephrology, Section of Cardio-Renal Physiology and Medicine, University of Alabama at Birmingham, Birmingham, AL 35233, U.K
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Bądzyńska B, Vaneckova I, Sadowski J, Hojná S, Kompanowska-Jezierska E. Effects of systemic and renal intramedullary endothelin-1 receptor blockade on tissue NO and intrarenal hemodynamics in normotensive and hypertensive rats. Eur J Pharmacol 2021; 910:174445. [PMID: 34492284 DOI: 10.1016/j.ejphar.2021.174445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 07/28/2021] [Accepted: 08/24/2021] [Indexed: 10/20/2022]
Abstract
Endothelin 1 (ET-1) seems essential in salt-dependent hypertension, and activation of ETA receptors causes renal vasoconstriction. However, the response in the renal medulla and the role of tissue NO availability has never been adequately explored in vivo. We examined effects of ETA and ETB receptor blockade (atrasentan and BQ788) on blood pressure (MAP), medullary blood flow (MBF) and medullary tissue NO. Effects of systemic and intramedullary blocker application were compared in anesthetized normotensive ET-1-pretreated Sprague-Dawley rats (S-D), in salt-dependent hypertension (HS/UNX) and in spontaneously hypertensive rats (SHR). Total renal blood flow (RBF) was measured using a Transonic renal artery probe, MBF as laser-Doppler flux, and tissue NO signal using selective electrodes. In normotensive rats ET-1 significantly increased MAP, decreased RBF (-20%) and renal medullary NO. In HS/UNX rats atrasentan decreased MAP and increased medullary NO, earlier and more profoundly with intravenous infusion. In SHR atrasentan decreased MAP, more effectively with intravenous infusion; the increase in tissue NO (∼10%) was similar with both routes; however, only intramedullary atrasentan increased MBF. No consistent responses to BQ788 were seen. We confirmed dominant role of ETA receptors in regulation of blood pressure and renal hemodynamics in normotensive and hypertensive rats and provided novel evidence for the role of ETA in control of intrarenal NO bioavailability in salt-dependent and spontaneous hypertension. Under conditions of activation of the endothelin system ETB stimulation preserved medullary perfusion.
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Affiliation(s)
- Bożena Bądzyńska
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Sciences, A. Pawińskiego 5, 02-106, Warsaw, Poland.
| | - Ivana Vaneckova
- Laboratory of Experimental Hypertension, Institute of Physiology, Czech Academy of Sciences, Czech Republic.
| | - Janusz Sadowski
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Sciences, A. Pawińskiego 5, 02-106, Warsaw, Poland.
| | - Silvie Hojná
- Laboratory of Experimental Hypertension, Institute of Physiology, Czech Academy of Sciences, Czech Republic.
| | - Elżbieta Kompanowska-Jezierska
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Sciences, A. Pawińskiego 5, 02-106, Warsaw, Poland.
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Fidelis HG, Mageski JGA, Goes SCE, Botelho T, Marques VB, Ávila RA, Dos Santos L. Blockade of angiotensin AT 1 receptors prevents arterial remodelling and stiffening in iron-overloaded rats. Br J Pharmacol 2020; 177:1119-1130. [PMID: 31705542 DOI: 10.1111/bph.14904] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 09/05/2019] [Accepted: 10/05/2019] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND AND PURPOSE Damage to the vasculature caused by chronic iron-overload in both humans and animal models, is characterized by endothelial dysfunction and reduced compliance. In vitro, blockade of the angiotensin II AT1 receptors reversed functional vascular changes induced by chronic iron-overload. In this study, the effect of chronic AT1 receptor blockade on aorta stiffening was assessed in iron-overloaded rats. EXPERIMENTAL APPROACH Male Wistar rats were treated for 15 days with saline as control group, iron dextran 200 mg·kg-1 ·day-1 , 5 days a week (iron-overload group), losartan (20 mg·kg-1 ·day-1 in drinking water), and iron dextran plus losartan. Mechanical properties of the aorta were assessed in vivo. In vitro, aortic geometry and biochemical composition were assessed with morphometric and histological methods. KEY RESULTS Thoracoabdominal aortic pulse wave velocity (PWV) increased significantly, indicating a decrease in aortic compliance. Co-treatment with losartan prevented changes on PWV, β-index, and elastic modulus in iron-overloaded rats. This iron-related increase in PWV was not related to changes in aortic geometry and wall stress. but to increased elastic modulus/wall stress ratio, suggesting that a change in the composition of the wall was responsible for the stiffness. Losartan treatment also ameliorated the increase in aorta collagen content of the iron-overload group, without affecting circulating iron or vascular deposits. CONCLUSIONS AND IMPLICATIONS Losartan prevented the structural and functional indices of aortic stiffness in iron-overloaded rats, implying that inhibition of the renin-angiotensin system would limit the vascular remodelling in chronic iron-overload.
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Affiliation(s)
| | | | | | - Tatiani Botelho
- Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, Brazil
| | | | | | - Leonardo Dos Santos
- Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, Brazil
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Guers JJ, Farquhar WB, Edwards DG, Lennon SL. Voluntary Wheel Running Attenuates Salt-Induced Vascular Stiffness Independent of Blood Pressure. Am J Hypertens 2019; 32:1162-1169. [PMID: 31401651 DOI: 10.1093/ajh/hpz128] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 06/17/2019] [Accepted: 07/31/2019] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Excess dietary salt can lead to the development of arterial stiffness and high blood pressure (BP). Regular physical activity can protect against arterial stiffening and lower BP. Less is known regarding the role of exercise on the vasculature independent of BP under high salt (HS) conditions. The aim of the study was to determine whether wheel running protects against the development of dietary salt-induced arterial stiffness independent of BP. METHODS Rats were maintained on either normal salt (NS; 0.49% NaCl) or HS (4.0% NaCl) diet for 6 weeks and further divided into a voluntary wheel running (NS-VWR, HS-VWR) or cage control group (NS, HS). Carotid-femoral pulse wave velocity (PWV) was measured using applanation tonometry at baseline (BSL) and 6 weeks. RESULTS BP was measured weekly and remained unchanged among groups throughout the 6 weeks (P > 0.05). PWV was elevated at 6 weeks in HS compared to baseline (HS-BSL, 3.27 ± 0.17 vs. HS-6 week, 4.13 ± 0.26 m/s; P < 0.05) and was lower at 6 weeks in both VWR groups (NS-VWR, 2.98 ± 0.29, HS-VWR, 3.11 ± 0.23 m/s) when compared to HS at 6 weeks (P < 0.05). This was supported by a significant increase in aortic collagen I in the HS group alone and transforming growth factor beta (TGF-β) was greater in the HS group compared to both NS groups (P < 0.05). Wheel running resulted in a greater aortic phosphorylated eNOS and SOD-2 in HS-WVR (P < 0.05) compared to HS. CONCLUSIONS These data suggest that VWR may protect against collagen accumulation through a TGF-β-mediated pathway by improving nitric oxide bioavailability and redox balance in rats.
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Affiliation(s)
- John J Guers
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware, USA
| | - William B Farquhar
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware, USA
| | - David G Edwards
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware, USA
| | - Shannon L Lennon
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware, USA
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Nishida N, Aoki H, Ohno-Urabe S, Nishihara M, Furusho A, Hirakata S, Hayashi M, Ito S, Yamada H, Hirata Y, Yasukawa H, Imaizumi T, Tanaka H, Fukumoto Y. High Salt Intake Worsens Aortic Dissection in Mice: Involvement of IL (Interleukin)-17A-Dependent ECM (Extracellular Matrix) Metabolism. Arterioscler Thromb Vasc Biol 2019; 40:189-205. [PMID: 31694392 PMCID: PMC6946107 DOI: 10.1161/atvbaha.119.313336] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE Aortic dissection (AD) is a fatal disease that occurs suddenly without preceding clinical signs or symptoms. Although high salt intake is a proposed risk factor for cardiovascular diseases, the relationship between AD and high salt intake has not been clarified. We examined the effect of high-salt challenge on a mouse AD model. Approach and Results: AD was induced in male mice by continuous infusion of β-aminopropionitrile and Ang II (angiotensin II). High-salt challenge exacerbated aortic wall destruction in AD. Deletion of Il17a (IL-17KO [IL (interleukin)-17A knockout]) did not affect the AD phenotype at baseline, but it abolished the high salt-induced worsening of the aortic destruction. Unexpectedly, aortas of IL-17KO mice exhibited global changes in ECM (extracellular matrix)-related genes without alteration of proinflammatory genes, altered architecture of collagen fibers, and reduced stiffness before AD induction. The aortas of IL-17KO mice were less sensitive to AD-inducing stimuli, as shown by the induction of phenotypic modulation markers SMemb and vimentin, suggesting a reduced stress response. The aortas of IL-17KO mice had a higher population of smooth muscle cells with nuclear-localized phosphorylated Smad2, indicative of TGFβ (transforming growth factor-beta) signal activation. Consistently, pretreatment of smooth muscle cells in culture with IL-17A blunted the activation of Smad2 by TGFβ1. CONCLUSIONS These findings indicate that high salt intake has a worsening effect on AD in the context of high aortic wall stiffness, which is under the control of IL-17A through ECM metabolism. Therefore, salt restriction may represent a low-cost and practical way to reduce AD risk.
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Affiliation(s)
- Norifumi Nishida
- From the Division of Cardiovascular Medicine, Department of Internal Medicine (N.N., S.O.-U., M.N., A.F., S.H., M.H., S.I., H. Yasukawa, Y.F.), Kurume University School of Medicine, Japan
| | - Hiroki Aoki
- Cardiovascular Research Institute, Kurume University, Japan (H.A.)
| | - Satoko Ohno-Urabe
- From the Division of Cardiovascular Medicine, Department of Internal Medicine (N.N., S.O.-U., M.N., A.F., S.H., M.H., S.I., H. Yasukawa, Y.F.), Kurume University School of Medicine, Japan
| | - Michihide Nishihara
- From the Division of Cardiovascular Medicine, Department of Internal Medicine (N.N., S.O.-U., M.N., A.F., S.H., M.H., S.I., H. Yasukawa, Y.F.), Kurume University School of Medicine, Japan
| | - Aya Furusho
- From the Division of Cardiovascular Medicine, Department of Internal Medicine (N.N., S.O.-U., M.N., A.F., S.H., M.H., S.I., H. Yasukawa, Y.F.), Kurume University School of Medicine, Japan
| | - Saki Hirakata
- From the Division of Cardiovascular Medicine, Department of Internal Medicine (N.N., S.O.-U., M.N., A.F., S.H., M.H., S.I., H. Yasukawa, Y.F.), Kurume University School of Medicine, Japan
| | - Makiko Hayashi
- From the Division of Cardiovascular Medicine, Department of Internal Medicine (N.N., S.O.-U., M.N., A.F., S.H., M.H., S.I., H. Yasukawa, Y.F.), Kurume University School of Medicine, Japan
| | - Sohei Ito
- From the Division of Cardiovascular Medicine, Department of Internal Medicine (N.N., S.O.-U., M.N., A.F., S.H., M.H., S.I., H. Yasukawa, Y.F.), Kurume University School of Medicine, Japan
| | - Hiroshi Yamada
- Department of Biological Functions Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, Japan (H. Yamada)
| | - Yuichiro Hirata
- Division of Cardiovascular Surgery, Department of Surgery (Y.H., H.T.), Kurume University School of Medicine, Japan
| | - Hideo Yasukawa
- From the Division of Cardiovascular Medicine, Department of Internal Medicine (N.N., S.O.-U., M.N., A.F., S.H., M.H., S.I., H. Yasukawa, Y.F.), Kurume University School of Medicine, Japan
| | - Tsutomu Imaizumi
- International University of Health and Welfare, Fukuoka, Japan (T.I.)
| | - Hiroyuki Tanaka
- Division of Cardiovascular Surgery, Department of Surgery (Y.H., H.T.), Kurume University School of Medicine, Japan
| | - Yoshihiro Fukumoto
- From the Division of Cardiovascular Medicine, Department of Internal Medicine (N.N., S.O.-U., M.N., A.F., S.H., M.H., S.I., H. Yasukawa, Y.F.), Kurume University School of Medicine, Japan
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Baldo MP, Rodrigues SL, Mill JG. High salt intake as a multifaceted cardiovascular disease: new support from cellular and molecular evidence. Heart Fail Rev 2016; 20:461-74. [PMID: 25725616 DOI: 10.1007/s10741-015-9478-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Scientists worldwide have disseminated the idea that increased dietary salt increases blood pressure. Currently, salt intake in the general population is ten times higher than that consumed in the past and at least two times higher than the current recommendation. Indeed, a salt-rich diet increases cardiovascular morbidity and mortality. For a long time, however, the deleterious effects associated with high salt consumption were only related to the effect of salt on blood pressure. Currently, several other effects have been reported. In some cases, the deleterious effects of high salt consumption are independently associated with other common risk factors. In this article, we gather data on the effects of increased salt intake on the cardiovascular system, from infancy to adulthood, to describe the route by which increased salt intake leads to cardiovascular diseases. We have reviewed the cellular and molecular mechanisms through which a high intake of salt acts on the cardiovascular system to lead to the progressive failure of a healthy heart.
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Affiliation(s)
- Marcelo Perim Baldo
- Department of Physiological Sciences, Federal University of Espírito Santo, Av Marechal Campos 1468, Maruipe, Vitória, ES, 29042-755, Brazil,
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Wong F. Cardiac changes in pediatric liver transplant recipients: are they truly irreversible? Hepatol Int 2016; 10:390-3. [PMID: 26884376 DOI: 10.1007/s12072-016-9708-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Accepted: 01/21/2016] [Indexed: 11/25/2022]
Affiliation(s)
- Florence Wong
- Division of Gastroenterology, Department of Medicine, Toronto General Hospital, University Health Network, University of Toronto, 200 Elizabeth Street, Toronto, ON, M5G 2C4, Canada.
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Fellner RC, Guan Z, Cook AK, Pollock DM, Inscho EW. Endothelin contributes to blunted renal autoregulation observed with a high-salt diet. Am J Physiol Renal Physiol 2015; 309:F687-96. [PMID: 26246513 DOI: 10.1152/ajprenal.00641.2014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 07/29/2015] [Indexed: 01/03/2023] Open
Abstract
Autoregulation of renal blood flow (RBF) is an essential function of the renal microcirculation that has been previously shown to be blunted by excessive dietary salt. Endogenous endothelin 1 (ET-1) is increased following a high-salt (HS) diet and contributes to the control of RBF but the differential effects of ET-1 on renal microvessel autoregulation in response to HS remain to be established. We hypothesized that a HS diet increases endothelin receptor activation in normal Sprague-Dawley rats and blunts autoregulation of RBF. The role of ET-1 in the blunted autoregulation produced by a HS diet was assessed in vitro and in vivo using the blood-perfused juxtamedullary nephron preparation and anesthetized rats, respectively. Using highly selective antagonists, we observed that blockade of either ETA or ETB receptors was sufficient to restore normal autoregulatory behavior in afferent arterioles from HS-fed rats. Additionally, normal autoregulatory behavior was restored in vivo in HS-fed rats by simultaneous ETA and ETB receptor blockade, whereas blockade of ETB receptors alone showed significant improvement of normal autoregulation of RBF. Consistent with this observation, autoregulation of RBF in ETB receptor-deficient rats fed HS was similar to both ETB-deficient rats and transgenic control rats on normal-salt diets. These data support the hypothesis that endogenous ET-1, working through ETB and possibly ETA receptors, contributes to the blunted renal autoregulatory behavior in rats fed a HS diet.
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Affiliation(s)
- Robert C Fellner
- Department of Physiology, Medical College of Georgia, Georgia Regents University, Augusta, Georgia
| | - Zhengrong Guan
- Department of Physiology, Medical College of Georgia, Georgia Regents University, Augusta, Georgia; Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Anthony K Cook
- Department of Physiology, Medical College of Georgia, Georgia Regents University, Augusta, Georgia; Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - David M Pollock
- Section of Experimental Medicine, Department of Medicine, Medical College of Georgia, Georgia Regents University, Augusta, Georgia; and Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Edward W Inscho
- Department of Physiology, Medical College of Georgia, Georgia Regents University, Augusta, Georgia; Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
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Zhang Y, Liou WW, Gupta V. Modeling of high sodium intake effects on left ventricular hypertrophy. Comput Biol Med 2015; 58:31-9. [PMID: 25601615 DOI: 10.1016/j.compbiomed.2014.12.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 12/06/2014] [Accepted: 12/18/2014] [Indexed: 01/19/2023]
Abstract
Many clinical studies suggest that chronic high sodium intake contributes to the development of essential hypertension and left ventricular (LV) hypertrophy. In the present study, a system-level computer model has been developed to simulate the long-term effects of increased sodium intake on the LV mechanical functions and the body-fluid homeostasis. The new model couples a cardiovascular hemodynamics function model with an explicit account of the LV wall thickness variation and a long-term renal system model. The present model is validated with published results of clinical studies. The results suggest that, with increased sodium intake, the renal system function, the plasma hormone concentrations, and the blood pressure adapt to new levels of equilibrium. The LV work output and the relative wall thickness increase due to the increase of sodium intake. The results of the present model match well with the patient data.
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Affiliation(s)
- Yan Zhang
- Department of Mechanical and Aerospace Engineering, Western Michigan University, Kalamazoo, Michigan, USA
| | - William W Liou
- Department of Mechanical and Aerospace Engineering, Western Michigan University, Kalamazoo, Michigan, USA.
| | - Vishal Gupta
- Borgess Medical Center, Borgess Research Institute, Kalamazoo, Michigan, USA
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Susic D, Fares H, Frohlich ED. Telmisartan Prevents Excess-Salt-Induced Exacerbated (Malignant) Hypertension in Spontaneously Hypertensive Rats. J Cardiovasc Pharmacol Ther 2013; 18:126-132. [DOI: 10.1177/1074248412458155] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
The effects of angiotensin receptor blocker, diuretic, a calcium antagonist, and their combination were evaluated on the progression of cardiovascular and renal damage in spontaneously hypertensive rats (SHRs) given excess salt. To this end, 8-week male SHRs were divided into 7 groups. The control group (C) received normal NaCl (0.6%) diet. All other groups were given 8% NaCl rat chow. In addition, group 2 was given placebo (tap water alone), group 3 the angiotensin receptor antagonist telmisartan (10 mg/kg per d), group 4 received the diuretic chlorothiazide (80 mg/kg per d), group 5 was given telmisartan plus the diuretic, group 6 was given the calcium antagonist amlodipine (10 mg/kg per d), and group 7 was given telmisartan plus amlodipine. All treatments lasted for 8 weeks. Compared with controls, mean arterial pressure (MAP), renal blood flow, coronary flow reserve, minimal coronary vascular resistance, diastolic time constant, and maximal rate of ventricular pressure fall were all adversely affected by salt loading. Increased left ventricular mass with marked cardiac fibrosis was also found in the salt-overloaded SHR group. Telmisartan normalized all indices except MAP, whereas diuretic and amlodipine only partially restored cardiac functional and mass indexes. Combination therapy with telmisartan and either diuretic or amlodipine also normalized all indices including arterial pressure. These data suggest that (1) cardiovascular damage induced by excess salt in the SHRs was not pressure dependent; (2) compared with the calcium antagonist and diuretic, blockade of angiotensin receptors was extremely effective in this model.
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Affiliation(s)
- Dinko Susic
- Hypertension Research Laboratory, Institute for Translational Research, Ochsner Clinic Foundation, New Orleans, LA, USA
| | - Hassan Fares
- Hypertension Research Laboratory, Institute for Translational Research, Ochsner Clinic Foundation, New Orleans, LA, USA
| | - Edward D. Frohlich
- Hypertension Research Laboratory, Institute for Translational Research, Ochsner Clinic Foundation, New Orleans, LA, USA
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Costa APR, de Paula RC, Carvalho GF, Araújo JP, Andrade JM, de Almeida OL, de Faria EC, Freitas WM, Coelho OR, Ramires JA, Quinaglia e Silva JC, Sposito AC. High sodium intake adversely affects oxidative-inflammatory response, cardiac remodelling and mortality after myocardial infarction. Atherosclerosis 2012; 222:284-91. [DOI: 10.1016/j.atherosclerosis.2012.02.037] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 01/09/2012] [Accepted: 02/24/2012] [Indexed: 10/28/2022]
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