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Stevenson MD, Vendrov AE, Yang X, Chen Y, Navarro HA, Moss N, Runge MS, Arendshorst WJ, Madamanchi NR. Reactivity of renal and mesenteric resistance vessels to angiotensin II is mediated by NOXA1/NOX1 and superoxide signaling. Am J Physiol Renal Physiol 2023; 324:F335-F352. [PMID: 36759130 PMCID: PMC10026993 DOI: 10.1152/ajprenal.00236.2022] [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: 09/06/2022] [Revised: 01/17/2023] [Accepted: 02/06/2023] [Indexed: 02/11/2023] Open
Abstract
Activation of NADPH oxidase (NOX) enzymes and the generation of reactive oxygen species and oxidative stress regulate vascular and renal function and contribute to the pathogenesis of hypertension. The present study examined the role of NOXA1/NOX1 function in vascular reactivity of renal and mesenteric resistance arteries/arterioles of wild-type and Noxa1-/- mice. A major finding was that renal blood flow is less sensitive to acute stimulation by angiotensin II (ANG II) in Noxa1-/- mice compared with wild-type mice, with a direct action on resistance arterioles independent of nitric oxide (NO) bioavailability. These functional results were reinforced by immunofluorescence evidence of NOXA1/NOX1 protein presence in renal arteries, afferent arterioles, and glomeruli as well as their upregulation by ANG II. In contrast, the renal vascular response to the thromboxane mimetic U46619 was effectively blunted by NO and was similar in both mouse genotypes and thus independent of NOXA1/NOX1 signaling. However, phenylephrine- and ANG II-induced contraction of isolated mesenteric arteries was less pronounced and buffering of vasoconstriction after acetylcholine and nitroprusside stimulation was reduced in Noxa1-/- mice, suggesting endothelial NO-dependent mechanisms. An involvement of NOXA1/NOX1/O2•- signaling in response to ANG II was demonstrated with the specific NOXA1/NOX1 assembly inhibitor C25 and the nonspecific NOX inhibitor diphenyleneiodonium chloride in cultured vascular smooth muscle cells and isolated mesenteric resistance arteries. Collectively, our data indicate that the NOX1/NOXA1/O2•- pathway contributes to acute vasoconstriction induced by ANG II in renal and mesenteric vascular beds and may contribute to ANG II-induced hypertension.NEW & NOTEWORTHY Renal reactivity to angiotensin II (ANG II) is mediated by superoxide signaling produced by NADPH oxidase (NOX)A1/NOX1. Acute vasoconstriction of renal arteries by ANG was blunted in Noxa1-/- compared with wild-type mice. NOXA1/NOX1/O2•- signaling was also observed in ANG II stimulation of vascular smooth muscle cells and isolated mesenteric resistance arteries, indicating that it contributes to ANG II-induced hypertension. A NOXA1/NOX1 assembly inhibitor (C25) has been characterized that inhibits superoxide production and ameliorates the effects of ANG II.
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Affiliation(s)
- Mark D Stevenson
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, United States
| | - Aleksandr E Vendrov
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, United States
| | - Xi Yang
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, North Carolina, United States
| | - Yuenmu Chen
- McAllister Heart Institute, Division of Cardiology, Department of Medicine, University of North Carolina, Chapel Hill, North Carolina, United States
| | - Hernán A Navarro
- Center for Drug Discovery, Organic and Medicinal Chemistry, RTI International, Research Triangle Park, North Carolina, United States
| | - Nicholas Moss
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, North Carolina, United States
| | - Marschall S Runge
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, United States
| | - William J Arendshorst
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, North Carolina, United States
| | - Nageswara R Madamanchi
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, United States
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Deng J, Li L, Feng Y, Yang J. Comprehensive Management of Blood Pressure in Patients with Septic AKI. J Clin Med 2023; 12:jcm12031018. [PMID: 36769666 PMCID: PMC9917880 DOI: 10.3390/jcm12031018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 01/18/2023] [Accepted: 01/19/2023] [Indexed: 01/31/2023] Open
Abstract
Acute kidney injury (AKI) is one of the serious complications of sepsis in clinical practice, and is an important cause of prolonged hospitalization, death, increased medical costs, and a huge medical burden to society. The pathogenesis of AKI associated with sepsis is relatively complex and includes hemodynamic abnormalities due to inflammatory response, oxidative stress, and shock, which subsequently cause a decrease in renal perfusion pressure and eventually lead to ischemia and hypoxia in renal tissue. Active clinical correction of hypotension can effectively improve renal microcirculatory disorders and promote the recovery of renal function. Furthermore, it has been found that in patients with a previous history of hypertension, small changes in blood pressure may be even more deleterious for kidney function. Therefore, the management of blood pressure in patients with sepsis-related AKI will directly affect the short-term and long-term renal function prognosis. This review summarizes the pathophysiological mechanisms of microcirculatory disorders affecting renal function, fluid management, vasopressor, the clinical blood pressure target, and kidney replacement therapy to provide a reference for the clinical management of sepsis-related AKI, thereby promoting the recovery of renal function for the purpose of improving patient prognosis.
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Affiliation(s)
- Junhui Deng
- Department of Nephrology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 400120, China
| | - Lina Li
- Department of Nephrology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 400120, China
| | - Yuanjun Feng
- Department of Renal Rheumatology, Space Hospital Affiliated to Zunyi Medical University, Zunyi 563002, China
| | - Jurong Yang
- Department of Nephrology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 400120, China
- Correspondence: or
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3
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Ye Q, Lan B, Liu H, Persson PB, Lai EY, Mao J. A critical role of the podocyte cytoskeleton in the pathogenesis of glomerular proteinuria and autoimmune podocytopathies. Acta Physiol (Oxf) 2022; 235:e13850. [PMID: 35716094 DOI: 10.1111/apha.13850] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/23/2022] [Accepted: 06/13/2022] [Indexed: 01/19/2023]
Abstract
Selective glomerular filtration relies on the membrane separating the glomerular arterioles from the Bowman space. As a major component of the glomerular filtration barrier, podocytes form foot processes by the actin cytoskeleton, which dynamically adjusts in response to environmental changes to maintain filtration barrier integrity. The slit diaphragms bridge the filtration slits between neighboring foot processes and act as signaling hubs interacting with the actin cytoskeleton. Focal adhesions relay signals to regulate actin dynamics while allowing podocyte adherence to the basement membrane. Mutations in actin regulatory and signaling proteins may disrupt the actin cytoskeleton, resulting in foot process retraction, effacement, and proteinuria. Large-scale gene expression profiling platforms, transgenic animal models, and other in vivo gene delivery methods now enhance our understanding of the interactions among podocyte focal adhesions, slit diaphragms, and actin dynamics. In addition, our team found that at least 66% of idiopathic nephrotic syndrome (INS) children have podocyte autoantibodies, which was defined as a new disease subgroup-, autoimmune podocytopathies. This review outlines the pathophysiological mechanisms of podocyte cytoskeleton protein interactions in proteinuria and glomerular podocytopathy.
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Affiliation(s)
- Qing Ye
- Department of Clinical Laboratory, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, National Children's Regional Medical Center, Hangzhou, China
| | - Bing Lan
- Department of Nephrology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, National Children's Regional Medical Center, Hangzhou, China
| | - Huihui Liu
- Department of Nephrology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, National Children's Regional Medical Center, Hangzhou, China
| | - Pontus B Persson
- Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Translational Physiology, Berlin, Germany
| | - En Yin Lai
- Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Translational Physiology, Berlin, Germany.,Department of Physiology, School of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou, China
| | - Jianhua Mao
- Department of Nephrology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, National Children's Regional Medical Center, Hangzhou, China
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4
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Jiang S, Wang X, Wei J, Zhang G, Zhang J, Xie P, Xu L, Wang L, Zhao L, Li L, Wilcox CS, Chen J, Lai EY, Liu R. NaHCO 3 Dilates Mouse Afferent Arteriole Via Na +/HCO 3- Cotransporters NBCs. Hypertension 2019; 74:1104-1112. [PMID: 31522618 DOI: 10.1161/hypertensionaha.119.13235] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Sodium bicarbonate has long been used to treat chronic kidney disease. It has been demonstrated to slow the decline in glomerular filtration rate in chronic kidney disease patient; however, the mechanisms are not completely understood. We hypothesized that NaHCO3 dilates afferent arterioles (Af-Art) by stimulating nitric oxide (NO) release mediated by the Na+/HCO3- cotransporter (NBC) contributing to the elevation in glomerular filtration rate. Isolated microperfused mouse renal Af-Art, preconstricted with norepinephrine (1 µmol/L), dilated 45±2% (n=6, P<0.05) in response to NaHCO3 (44 mmol/L). Whereas, NaCl solution containing the same Na+ concentration was not effective. The mRNA for NBCn1 and NBCe1 were detected in microdissected Af-Art using reverse transcription-polymerase chain reaction and quantitative polymerase chain reaction. The Af-Art intracellular pH measured with 2',7'-bis-(2-carboxyethyl)-5-(and-6) carboxyfluorescein, acetoxymethyl ester increased significantly by 0.29±0.02 (n=6; P<0.05) in the presence of NaHCO3, which was blunted by N-cyanosulphonamide compound (S0859) that is an inhibitor of the NBC family. After clamping the intracellular pH with 10 μM nigericin, changing the bath solution pH from 7.4 to 7.8 still dilates the Af-Art by 53±4% (n=7; P<0.005) and increases NO generation by 22±3% (n=7; P<0.005). Both pH-induced NO generation and vasodilation were blocked by L-NG-Nitroarginine Methyl Ester. NaHCO3 increased NO generation in Af-Art by 19±4% (n=5; P<0.005) and elevated glomerular filtration rate in conscious mice by 36% (233 versus 318 ul/min; n=9-10; P<0.0001). S0859 and L-NG-nitroarginine methyl ester blocked NaHCO3-induced increases in NO generation and vasodilation. We conclude that NBCn1 and NBCe1 are expressed in Af-Art and that NaHCO3 dilates Af-Art via NBCs mediated by NO that increases the glomerular filtration rate.
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Affiliation(s)
- Shan Jiang
- From Kidney Disease Center, the First Affiliated Hospital, and Department of Physiology, School of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou, China (S.J., G.Z., P.X., L.Z., L.L., J.C., E.Y.L.).,Department of Molecular Pharmacology and Physiology, University of South Florida College of Medicine, Tampa (S.J., X.W., J.W., G.Z., J.Z., L.W., R.L.)
| | - Ximing Wang
- Department of Molecular Pharmacology and Physiology, University of South Florida College of Medicine, Tampa (S.J., X.W., J.W., G.Z., J.Z., L.W., R.L.).,Shandong Provincial Hospital, Affiliated Hospital of Shandong University, Jinan, China (X.W.)
| | - Jin Wei
- Department of Molecular Pharmacology and Physiology, University of South Florida College of Medicine, Tampa (S.J., X.W., J.W., G.Z., J.Z., L.W., R.L.)
| | - Gensheng Zhang
- From Kidney Disease Center, the First Affiliated Hospital, and Department of Physiology, School of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou, China (S.J., G.Z., P.X., L.Z., L.L., J.C., E.Y.L.).,Department of Molecular Pharmacology and Physiology, University of South Florida College of Medicine, Tampa (S.J., X.W., J.W., G.Z., J.Z., L.W., R.L.)
| | - Jie Zhang
- Department of Molecular Pharmacology and Physiology, University of South Florida College of Medicine, Tampa (S.J., X.W., J.W., G.Z., J.Z., L.W., R.L.)
| | - Peng Xie
- From Kidney Disease Center, the First Affiliated Hospital, and Department of Physiology, School of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou, China (S.J., G.Z., P.X., L.Z., L.L., J.C., E.Y.L.)
| | - Lan Xu
- College of Public Health, University of South Florida, Tampa (L.X.)
| | - Lei Wang
- Department of Molecular Pharmacology and Physiology, University of South Florida College of Medicine, Tampa (S.J., X.W., J.W., G.Z., J.Z., L.W., R.L.)
| | - Liang Zhao
- From Kidney Disease Center, the First Affiliated Hospital, and Department of Physiology, School of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou, China (S.J., G.Z., P.X., L.Z., L.L., J.C., E.Y.L.).,Department of Physiology, School of Basic Medical Sciences, Guangzhou Medical University, China (L.Z., E.Y.L.).,Institute of Vegetative Physiology, Charité-Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, Germany (L.Z., E.Y.L.)
| | - Lingli Li
- From Kidney Disease Center, the First Affiliated Hospital, and Department of Physiology, School of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou, China (S.J., G.Z., P.X., L.Z., L.L., J.C., E.Y.L.).,Division of Nephrology and Hypertension, and Hypertension Center, Georgetown University, Washington, DC (L.L., C.S.W.)
| | - Christopher S Wilcox
- Division of Nephrology and Hypertension, and Hypertension Center, Georgetown University, Washington, DC (L.L., C.S.W.)
| | - Jianghua Chen
- From Kidney Disease Center, the First Affiliated Hospital, and Department of Physiology, School of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou, China (S.J., G.Z., P.X., L.Z., L.L., J.C., E.Y.L.)
| | - En Yin Lai
- From Kidney Disease Center, the First Affiliated Hospital, and Department of Physiology, School of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou, China (S.J., G.Z., P.X., L.Z., L.L., J.C., E.Y.L.).,Department of Physiology, School of Basic Medical Sciences, Guangzhou Medical University, China (L.Z., E.Y.L.).,Institute of Vegetative Physiology, Charité-Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, Germany (L.Z., E.Y.L.)
| | - Ruisheng Liu
- Department of Molecular Pharmacology and Physiology, University of South Florida College of Medicine, Tampa (S.J., X.W., J.W., G.Z., J.Z., L.W., R.L.)
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5
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Jiang H, Liang L, Qin J, Lu Y, Li B, Wang Y, Lin C, Zhou Q, Feng S, Yip SH, Xu F, Lai EY, Wang J, Chen J. Functional networks of aging markers in the glomeruli of IgA nephropathy: a new therapeutic opportunity. Oncotarget 2018; 7:33616-26. [PMID: 27127888 PMCID: PMC5085107 DOI: 10.18632/oncotarget.9033] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Accepted: 04/11/2016] [Indexed: 12/12/2022] Open
Abstract
IgA nephropathy(IgAN) is the most common primary glomerular disease in China. Primary infections always occur before IgAN. However, the pathology of IgAN is still unclear. Previously we found that LL37, a protein secreted by senescent cells, was specific for the progression of IgAN, and also played a role in the neutrophil function. So we hypothesized that the infiltration of neutrophils, inflammation factors, and aging markers, which were modulated by functional networks, induced the immune response and renal injury. RNA-Sequencing (RNA-seq) can be used to study the whole transcriptome and detect splicing variants that are expressed in a specific cell type or tissue. We separate glomerulus from the renal biopsy tissues. After RNA extraction, the sequences were analyzed with Illumina HiSeq 2000/2500. 381 genes with differential expression between the IgAN patients and the healthy controls were identified. Only PLAU, JUN, and FOS were related to DNA damage, telomere dysfunction-induced aging markers, neutrophil function and IgA nephropathy. The networks showed the possibility of these genes being connected. We conclude that DNA damage and telomere dysfunction could play important roles in IgA nephropathy. In addition, neutrophils are also important factors in this disease. The networks of these markers showed the mechanism pathways that are involved in the duration of the occurrence and progression of IgA nephropathy and might be a new therapeutic opportunity for disease treatment.
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Affiliation(s)
- Hong Jiang
- Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, P.R. China.,Kidney Disease Immunology Laboratory, The Third Grade Laboratory, State Administration Of Traditional Chinese Medicine Of China, Hangzhou, P.R. China.,Key Laboratory Of Multiple Organ Transplantation, Ministry Of Health, Key Laboratory Of Nephropathy, Zhejiang, P.R. China
| | - Ludan Liang
- Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, P.R. China.,Kidney Disease Immunology Laboratory, The Third Grade Laboratory, State Administration Of Traditional Chinese Medicine Of China, Hangzhou, P.R. China.,Key Laboratory Of Multiple Organ Transplantation, Ministry Of Health, Key Laboratory Of Nephropathy, Zhejiang, P.R. China
| | - Jing Qin
- School of Life Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China.,School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Yingying Lu
- Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, P.R. China.,Kidney Disease Immunology Laboratory, The Third Grade Laboratory, State Administration Of Traditional Chinese Medicine Of China, Hangzhou, P.R. China.,Key Laboratory Of Multiple Organ Transplantation, Ministry Of Health, Key Laboratory Of Nephropathy, Zhejiang, P.R. China
| | - Bingjue Li
- Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, P.R. China.,Kidney Disease Immunology Laboratory, The Third Grade Laboratory, State Administration Of Traditional Chinese Medicine Of China, Hangzhou, P.R. China.,Key Laboratory Of Multiple Organ Transplantation, Ministry Of Health, Key Laboratory Of Nephropathy, Zhejiang, P.R. China
| | - Yucheng Wang
- Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, P.R. China.,Kidney Disease Immunology Laboratory, The Third Grade Laboratory, State Administration Of Traditional Chinese Medicine Of China, Hangzhou, P.R. China.,Key Laboratory Of Multiple Organ Transplantation, Ministry Of Health, Key Laboratory Of Nephropathy, Zhejiang, P.R. China
| | - Chuan Lin
- Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, P.R. China.,Kidney Disease Immunology Laboratory, The Third Grade Laboratory, State Administration Of Traditional Chinese Medicine Of China, Hangzhou, P.R. China.,Key Laboratory Of Multiple Organ Transplantation, Ministry Of Health, Key Laboratory Of Nephropathy, Zhejiang, P.R. China
| | - Qin Zhou
- Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, P.R. China.,Kidney Disease Immunology Laboratory, The Third Grade Laboratory, State Administration Of Traditional Chinese Medicine Of China, Hangzhou, P.R. China.,Key Laboratory Of Multiple Organ Transplantation, Ministry Of Health, Key Laboratory Of Nephropathy, Zhejiang, P.R. China
| | - Shi Feng
- Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, P.R. China.,Kidney Disease Immunology Laboratory, The Third Grade Laboratory, State Administration Of Traditional Chinese Medicine Of China, Hangzhou, P.R. China.,Key Laboratory Of Multiple Organ Transplantation, Ministry Of Health, Key Laboratory Of Nephropathy, Zhejiang, P.R. China
| | - Shun H Yip
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Feng Xu
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - En Yin Lai
- Department of Physiology, Zhejiang University School of Medicine, Hangzhou, P.R. China
| | - Junwen Wang
- Centre for Genomic Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China.,School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Jianghua Chen
- Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, P.R. China.,Kidney Disease Immunology Laboratory, The Third Grade Laboratory, State Administration Of Traditional Chinese Medicine Of China, Hangzhou, P.R. China.,Key Laboratory Of Multiple Organ Transplantation, Ministry Of Health, Key Laboratory Of Nephropathy, Zhejiang, P.R. China
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6
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Vinturache AE, Smith FG. Glomerular and tubular effects of nitric oxide (NO) are regulated by angiotensin II (Ang II) in an age-dependent manner through activation of both angiotensin receptors (AT1Rs and AT2Rs) in conscious lambs. Pflugers Arch 2017; 470:249-261. [PMID: 28861607 DOI: 10.1007/s00424-017-2053-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2017] [Revised: 07/23/2017] [Accepted: 08/02/2017] [Indexed: 01/01/2023]
Abstract
Renin-angiotensin (RAS) and nitric oxide (NO) systems and the balance and interaction between them are considered of primary importance in maintaining fluid and electrolyte homeostasis. It has been suggested that the effects of NO may be modulated at least in part by the angiotensin (Ang) II, yet the roles of angiotensin receptor type 1 (AT1R) and type 2 (AT2R) are not well understood. Even though both Ang II and NO are elevated at birth and during the newborn period, their contribution to the adaptation of the newborn to life after birth as well as their physiological roles during development are poorly understood. The aim of this study was to determine if NO regulation of renal function during postnatal maturation is modulated by Ang II through activation of AT1R or AT2R or both receptors. Glomerular and tubular effects of either AT1R selective antagonist ZD 7155, AT2R selective antagonist PD 123319, and both antagonists ZD 7155 plus PD 123319, were measured in 1- (N = 9) and 6-week-old (N = 13) conscious, chronically instrumented lambs before and after removal of endogenous NO with L-arginine analogue, L-NAME. Two-way analysis of variance (ANOVA) procedures for repeated measures over time with factors age and treatment were used to compare the effects of the treatments on several glomerular and tubular variables in both groups. This study showed that L-NAME infusion after pre-treatment with ATR antagonists did not alter glomerular function in 1- or 6-week-old lambs. NO effects on electrolytes handling along the nephron during postnatal development were modulated by Ang II through AT1R and AT2R in an age-dependent manner. Selective inhibition of AT1R and AT2R increased excretion of Na+, K+, and Cl- in 6- but not in 1-week-old lambs. In 6-week-old lambs, urinary flow rate increased by 200%, free water clearance increased by 50%, and urine osmolality decreased by 40% after L-NAME was added to the pre-treatment with ZD 7155 plus PD 123319. When L-NAME was added either to ZD 7155 or PD 123319, the same trend in the alterations of these variables was observed, albeit to a lower degree. In conclusion, in conscious animals, during postnatal maturation, Ang II modulates the effects of NO on glomerular function, fluid, and electrolyte homeostasis through AT1Rs and AT2Rs in an age-dependent manner. Under physiological conditions, AT2Rs may potentiate the effects of AT1R, providing evidence of a crosstalk between ATRs in modulating NO effects on fluid and electrolyte homeostasis during postnatal maturation. This study provides new insights on the regulation of renal function during early postnatal development showing that, compared with later in life, newborns have impaired capacity to regulate glomerular function, water, and electrolyte balance.
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Affiliation(s)
- Angela E Vinturache
- Department of Physiology and Pharmacology, Alberta Children's Hospital Research Institute for Child and Maternal Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
| | - Francine G Smith
- Department of Physiology and Pharmacology, Alberta Children's Hospital Research Institute for Child and Maternal Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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Jin J, Tang Q, Li Z, Zhao Z, Zhang Z, Lu L, Zhu T, Vanhoutte PM, Leung SW, Tu R, Shi Y. Prostaglandin E 2 regulates renal function in C57/BL6 mouse with 5/6 nephrectomy. Life Sci 2017; 174:68-76. [PMID: 28263803 DOI: 10.1016/j.lfs.2017.03.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 02/27/2017] [Accepted: 03/01/2017] [Indexed: 12/26/2022]
Abstract
AIMS To investigate the roles of cyclooxygenases (COX) and their metabolites in C57/BL6 mice with 5/6 nephrectomy, an animal model of chronic renal failure. MAIN METHODS C57/BL6 mice were grouped into sham-operated (2K), one kidney removal (1K) and 5/6 nephrectomy groups (5/6Nx). Renal resistive index was measured by ultrasonography. Blood, aortae, renal arteries and renal cortex were collected for measurement of kidney function, assessment of vascular responsiveness, Western blotting, immuohistochemistry and enzyme-linked immunosorbent assays. KEY FINDINGS After four weeks, acetylcholine-induced relaxations were blunted in renal arteries of 1K and 5/6Nx mice; indomethacin, a non-selective COX inhibitor, improved the response in 5/6Nx, but not in 1K renal arteries. In 5/6Nx renal arteries, but not in 1K preparations, the protein presence of endothelial nitric oxide synthase (eNOS) was decreased, while that of COX-2 and its products [prostacyclin and thromboxane A2] were increased. The renal resistive index was lower in 5/6Nx mice, suggesting a lower resistance in the renal microvasculature. In the renal cortex of 5/6Nx mice, eNOS protein presence was increased; while the presence of COX-2 was not detectable. The prostaglandin E2 level was lower in the 5/6Nx cortex than in the other two groups. SIGNIFICANCE The early stage of renal mass removal is associated with increased renal arterial constriction and reduced microvascular resistance. The former is due to downregulation of eNOS and upregulation of COX-2, leading to an increased production of prostacyclin and thromboxane A2. A reduced production of PGE2 in the renal cortex is important for maintaining normal renal function.
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Affiliation(s)
- J Jin
- Biomedical Research Centre, Zhongshan Hospital, Fudan University, China
| | - Q Tang
- Department of Urology, Zhongshan Hospital, Fudan University, China; Shanghai Key Laboratory of Organ Transplantation, China
| | - Z Li
- Biomedical Research Centre, Zhongshan Hospital, Fudan University, China
| | - Z Zhao
- Department of Pathology, Faculty of Medicine, Fudan University, China
| | - Z Zhang
- Department of Pathology, Faculty of Medicine, Fudan University, China
| | - L Lu
- Department of Physiology and Pathophysiology, Faculty of Medicine, Fudan University, China
| | - T Zhu
- Department of Urology, Zhongshan Hospital, Fudan University, China; Shanghai Key Laboratory of Organ Transplantation, China
| | - P M Vanhoutte
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
| | - S W Leung
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
| | - R Tu
- Department of Obstetrics and Gynecology, Zhongshan Hospital, Fudan University, China.
| | - Y Shi
- Biomedical Research Centre, Zhongshan Hospital, Fudan University, China; Shanghai Key Laboratory of Organ Transplantation, China.
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8
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Jansson L, Barbu A, Bodin B, Drott CJ, Espes D, Gao X, Grapensparr L, Källskog Ö, Lau J, Liljebäck H, Palm F, Quach M, Sandberg M, Strömberg V, Ullsten S, Carlsson PO. Pancreatic islet blood flow and its measurement. Ups J Med Sci 2016; 121:81-95. [PMID: 27124642 PMCID: PMC4900068 DOI: 10.3109/03009734.2016.1164769] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Pancreatic islets are richly vascularized, and islet blood vessels are uniquely adapted to maintain and support the internal milieu of the islets favoring normal endocrine function. Islet blood flow is normally very high compared with that to the exocrine pancreas and is autonomously regulated through complex interactions between the nervous system, metabolites from insulin secreting β-cells, endothelium-derived mediators, and hormones. The islet blood flow is normally coupled to the needs for insulin release and is usually disturbed during glucose intolerance and overt diabetes. The present review provides a brief background on islet vascular function and especially focuses on available techniques to measure islet blood perfusion. The gold standard for islet blood flow measurements in experimental animals is the microsphere technique, and its advantages and disadvantages will be discussed. In humans there are still no methods to measure islet blood flow selectively, but new developments in radiological techniques hold great hopes for the future.
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Affiliation(s)
- Leif Jansson
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
- CONTACT Leif Jansson, Department of Medical Cell Biology, Biomedical Centre, Box 571, Husargatan 3, SE-75123 Uppsala, Sweden
| | - Andreea Barbu
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Birgitta Bodin
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Carl Johan Drott
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Daniel Espes
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Xiang Gao
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Liza Grapensparr
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Örjan Källskog
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Joey Lau
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Hanna Liljebäck
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Fredrik Palm
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - My Quach
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Monica Sandberg
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | | | - Sara Ullsten
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Per-Ola Carlsson
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
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Bäumler H, Xiong Y, Liu ZZ, Patzak A, Georgieva R. Novel Hemoglobin Particles-Promising New-Generation Hemoglobin-Based Oxygen Carriers. Artif Organs 2014; 38:708-14. [DOI: 10.1111/aor.12331] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Hans Bäumler
- Institute of Transfusion Medicine and Berlin-Brandenburg Center for Regenerative Therapies; Charité-Universitätsmedizin Berlin; Berlin Germany
| | - Yu Xiong
- Institute of Transfusion Medicine and Berlin-Brandenburg Center for Regenerative Therapies; Charité-Universitätsmedizin Berlin; Berlin Germany
| | - Zhi Zhao Liu
- Institute of Vegetative Physiology; Charité-Universitätsmedizin Berlin; Berlin Germany
| | - Andreas Patzak
- Institute of Vegetative Physiology; Charité-Universitätsmedizin Berlin; Berlin Germany
| | - Radostina Georgieva
- Institute of Transfusion Medicine and Berlin-Brandenburg Center for Regenerative Therapies; Charité-Universitätsmedizin Berlin; Berlin Germany
- Department of Medical Physics; Biophysics and Image Diagnostics; Medical Faculty; Trakia University; Stara Zagora Bulgaria
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Takahashi T, Harris RC. Role of endothelial nitric oxide synthase in diabetic nephropathy: lessons from diabetic eNOS knockout mice. J Diabetes Res 2014; 2014:590541. [PMID: 25371905 PMCID: PMC4211249 DOI: 10.1155/2014/590541] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2014] [Accepted: 09/08/2014] [Indexed: 12/29/2022] Open
Abstract
Diabetic nephropathy (DN) is the leading cause of end-stage renal disease in many countries. The animal models that recapitulate human DN undoubtedly facilitate our understanding of this disease and promote the development of new diagnostic markers and therapeutic interventions. Based on the clinical evidence showing the association of eNOS dysfunction with advanced DN, we and others have created diabetic mice that lack eNOS expression and shown that eNOS-deficient diabetic mice exhibit advanced nephropathic changes with distinct features of progressive DN, including pronounced albuminuria, nodular glomerulosclerosis, mesangiolysis, and arteriolar hyalinosis. These studies clearly defined a critical role of eNOS in DN and developed a robust animal model of this disease, which enables us to study the pathogenic mechanisms of progressive DN. Further, recent studies with this animal model have explored the novel mechanisms by which eNOS deficiency causes advanced DN and provided many new insights into the pathogenesis of DN. Therefore, here we summarize the findings obtained with this animal model and discuss the roles of eNOS in DN, unresolved issues, and future investigations of this animal model study.
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Affiliation(s)
- Takamune Takahashi
- Division of Nephrology and Hypertension, Vanderbilt University School of Medicine, S-3223, Medical Center North, Nashville, TN 37232, USA
- *Takamune Takahashi:
| | - Raymond C. Harris
- Division of Nephrology and Hypertension, Vanderbilt University School of Medicine, S-3223, Medical Center North, Nashville, TN 37232, USA
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Abstract
SIGNIFICANCE Renal oxidative stress can be a cause, a consequence, or more often a potentiating factor for hypertension. Increased reactive oxygen species (ROS) in the kidney have been reported in multiple models of hypertension and related to renal vasoconstriction and alterations of renal function. Nicotinamide adenine dinucleotide phosphate oxidase is the central source of ROS in the hypertensive kidney, but a defective antioxidant system also can contribute. RECENT ADVANCES Superoxide has been identified as the principal ROS implicated for vascular and tubular dysfunction, but hydrogen peroxide (H2O2) has been implicated in diminishing preglomerular vascular reactivity, and promoting medullary blood flow and pressure natriuresis in hypertensive animals. CRITICAL ISSUES AND FUTURE DIRECTIONS Increased renal ROS have been implicated in renal vasoconstriction, renin release, activation of renal afferent nerves, augmented contraction, and myogenic responses of afferent arterioles, enhanced tubuloglomerular feedback, dysfunction of glomerular cells, and proteinuria. Inhibition of ROS with antioxidants, superoxide dismutase mimetics, or blockers of the renin-angiotensin-aldosterone system or genetic deletion of one of the components of the signaling cascade often attenuates or delays the onset of hypertension and preserves the renal structure and function. Novel approaches are required to dampen the renal oxidative stress pathways to reduced O2(-•) rather than H2O2 selectivity and/or to enhance the endogenous antioxidant pathways to susceptible subjects to prevent the development and renal-damaging effects of hypertension.
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Affiliation(s)
- Magali Araujo
- Hypertension, Kidney and Vascular Research Center, Georgetown University , Washington, District of Columbia
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Xiong Y, Liu ZZ, Georgieva R, Smuda K, Steffen A, Sendeski M, Voigt A, Patzak A, Bäumler H. Nonvasoconstrictive hemoglobin particles as oxygen carriers. ACS NANO 2013; 7:7454-7461. [PMID: 23915101 DOI: 10.1021/nn402073n] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Artificial oxygen carriers, favorably hemoglobin-based oxygen carriers (HBOCs), are being investigated intensively during the last 30 years with the aim to develop a universal blood substitute. However, serious side effects mainly caused by vasoconstriction triggered by nitric oxide (NO) scavenging due to penetration of nanosized HBOCs through the endothelial gaps of the capillary walls and/or oxygen oversupply in the precapillary arterioles due to their low oxygen affinity led to failure of clinical trials and FDA disapproval. To avoid these effects, HBOCs with a size between 100 and 1000 nm and high oxygen affinity are needed. Here we present for the first time unique hemoglobin particles (HbPs) of around 700 nm with high oxygen affinity and low immunogenicity using a novel, highly effective, and simple technique. The fabrication procedure provides particles with a narrow size distribution and nearly uniform morphology. The content of hemoglobin (Hb) in the particles corresponded to 80% of the Hb content in native erythrocytes. Furthermore, we demonstrate a successful perfusion of isolated mouse glomeruli with concentrated HbP suspensions in vitro. A normal, nonvasoconstrictive behavior of the afferent arterioles is observed, suggesting no oxygen oversupply and limited NO scavenging by these particles, making them a highly promising blood substitute.
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Affiliation(s)
- Yu Xiong
- Institute of Transfusion Medicine and Berlin-Brandenburg Center for Regenerative Therapies, Charité-Universitätsmedizin Berlin , Charitéplatz 1, 10117 Berlin, Germany
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Liu ZZ, Viegas VU, Perlewitz A, Lai EY, Persson PB, Patzak A, Sendeski MM. Iodinated Contrast Media Differentially Affect Afferent and Efferent Arteriolar Tone and Reactivity in Mice: A Possible Explanation for Reduced Glomerular Filtration Rate. Radiology 2012; 265:762-71. [DOI: 10.1148/radiol.12120044] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Understanding the mechanisms of proteinuria: therapeutic implications. Int J Nephrol 2012; 2012:546039. [PMID: 22844592 PMCID: PMC3398673 DOI: 10.1155/2012/546039] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Accepted: 04/30/2012] [Indexed: 12/18/2022] Open
Abstract
A large body of evidence indicates that proteinuria is a strong predictor of morbidity, a cause of inflammation, oxidative stress and progression of chronic kidney disease, and development of cardiovascular disease. The processes that lead to proteinuria are complex and involve factors such as glomerular hemodynamic, tubular absorption, and diffusion gradients. Alterations in various different molecular pathways and interactions may lead to the identical clinical end points of proteinuria and chronic kidney disease. Glomerular diseases include a wide range of immune and nonimmune insults that may target and thus damage some components of the glomerular filtration barrier. In many of these conditions, the renal visceral epithelial cell (podocyte) responds to injury along defined pathways, which may explain the resultant clinical and histological changes. The recent discovery of the molecular components of the slit diaphragm, specialized structure of podocyte-podocyte interaction, has been a major breakthrough in understanding the crucial role of the epithelial layer of the glomerular barrier and the pathogenesis of proteinuria. This paper provides an overview and update on the structure and function of the glomerular filtration barrier and the pathogenesis of proteinuria, highlighting the role of the podocyte in this setting. In addition, current antiproteinuric therapeutic approaches are briefly commented.
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Arya A, Yadav HN, Sharma PL. Involvement of vascular endothelial nitric oxide synthase in development of experimental diabetic nephropathy in rats. Mol Cell Biochem 2011; 354:57-66. [DOI: 10.1007/s11010-011-0805-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Accepted: 03/24/2011] [Indexed: 11/29/2022]
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Carpentier X, Traxer O, Lechevallier E, Saussine C. [Physiopathology of acute renal colic]. Prog Urol 2008; 18:844-8. [PMID: 19033041 DOI: 10.1016/j.purol.2008.09.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2008] [Accepted: 09/02/2008] [Indexed: 10/21/2022]
Affiliation(s)
- X Carpentier
- Service d'urologie, hôpital Tenon, 4, rue de la Chine, 75970 Paris cedex 20, France
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Palm F, Connors SG, Mendonca M, Welch WJ, Wilcox CS. Angiotensin II type 2 receptors and nitric oxide sustain oxygenation in the clipped kidney of early Goldblatt hypertensive rats. Hypertension 2007; 51:345-51. [PMID: 18158356 DOI: 10.1161/hypertensionaha.107.097832] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Angiotensin-converting enzyme inhibitors (ACEIs) decrease the glomerular filtration rate and renal blood flow in the clipped kidneys of early 2-kidney, 1-clip Goldblatt hypertensive rats, but the consequences for oxygenation are unclear. We investigated the hypothesis that angiotensin II type 1 or angiotensin II type 2 receptors or NO synthase mediate renal oxygenation responses to ACEI. Three weeks after left renal artery clipping, kidney function, oxygen (O(2)) use, renal blood flow, renal cortical blood flow, and renal cortical oxygen tension (Po(2)) were measured after acute administration of an ACEI (enalaprilat) and after acute administration of ACEI following acute administration of an angiotensin II type 1 or angiotensin II type 2 receptor blocker (candesartan or PD-123,319) or an NO synthase blocker (N(G)-nitro-L-arginine methyl ester with control of renal perfusion pressure) and compared with mechanical reduction in renal perfusion pressure to the levels after ACEI. The basal renal cortical Po(2) of clipped kidneys was significantly lower than contralateral kidneys (35+/-1 versus 51+/-1 mm Hg; n=40 each). ACEI lowered renal venous Po(2), cortical Po(2), renal blood flow, glomerular filtration rate, and cortical blood flow and increased the renal vascular resistance in the clipped kidney, whereas mechanical reduction in renal perfusion pressure was ineffective. PD-123,319 and N(G)-nitro-L-arginine methyl ester, but not candesartan, reduced the Po(2) of clipped kidneys and blocked the fall in Po(2) with acute ACEI administration. In conclusion, oxygen availability in the clipped kidney is maintained by angiotensin II generation, angiotensin II type 2 receptors, and NO synthase. This discloses a novel mechanism whereby angiotensin can prevent hypoxia in a kidney challenged with a reduced perfusion pressure.
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Affiliation(s)
- Fredrik Palm
- Division of Nephrology and Hypertension, Cardiovascular Kidney Hypertension Institute, Georgetown University, 3800 Reservoir Rd, NW, PHC F6003, Washington, DC 20007, USA
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Stegbauer J, Kuczka Y, Vonend O, Quack I, Sellin L, Patzak A, Steege A, Langnaese K, Rump LC. Endothelial nitric oxide synthase is predominantly involved in angiotensin II modulation of renal vascular resistance and norepinephrine release. Am J Physiol Regul Integr Comp Physiol 2007; 294:R421-8. [PMID: 18046021 DOI: 10.1152/ajpregu.00481.2007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nitric oxide (NO) is mainly generated by endothelial NO synthase (eNOS) or neuronal NOS (nNOS). Recent studies indicate that angiotensin II generates NO release, which modulates renal vascular resistance and sympathetic neurotransmission. Experiments in wild-type [eNOS(+/+) and nNOS(+/+)], eNOS-deficient [eNOS(-/-)], and nNOS-deficient [nNOS(-/-)] mice were performed to determine which NOS isoform is involved. Isolated mice kidneys were perfused with Krebs-Henseleit solution. Endogenous norepinephrine release was measured by HPLC. Angiotensin II dose dependently increased renal vascular resistance in all mice species. EC(50) and maximal pressor responses to angiotensin II were greater in eNOS(-/-) than in nNOS(-/-) and smaller in wild-type mice. The nonselective NOS inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME; 0.3 mM) enhanced angiotensin II-induced pressor responses in nNOS(-/-) and wild-type mice but not in eNOS(-/-) mice. In nNOS(+/+) mice, 7-nitroindazole monosodium salt (7-NINA; 0.3 mM), a selective nNOS inhibitor, enhanced angiotensin II-induced pressor responses slightly. Angiotensin II-enhanced renal nerve stimulation induced norepinephrine release in all species. L-NAME (0.3 mM) reduced angiotensin II-mediated facilitation of norepinephrine release in nNOS(-/-) and wild-type mice but not in eNOS(-/-) mice. 7-NINA failed to modulate norepinephrine release in nNOS(+/+) mice. (4-Chlorophrnylthio)guanosine-3', 5'-cyclic monophosphate (0.1 nM) increased norepinephrine release. mRNA expression of eNOS, nNOS, and inducible NOS did not differ between mice strains. In conclusion, angiotensin II-mediated effects on renal vascular resistance and sympathetic neurotransmission are modulated by NO in mice. These effects are mediated by eNOS and nNOS, but NO derived from eNOS dominates. Only NO derived from eNOS seems to modulate angiotensin II-mediated renal norepinephrine release.
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Affiliation(s)
- Johannes Stegbauer
- Klinik für Nephrologie der Universitätsklinik Düsseldorf, Heinrich-Heine-Universität Düsseldorf, Moorenstrasse 5, 40225 Düsseldorf, Germany
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Daubert DL, Liu D, Zucker IH, Brooks VL. Roles of nitric oxide and angiotensin II in the impaired baroreflex gain of pregnancy. Am J Physiol Regul Integr Comp Physiol 2007; 292:R2179-87. [PMID: 17379846 DOI: 10.1152/ajpregu.00026.2007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The present study tested the hypothesis that nitric oxide (NO) contributes to impaired baroreflex gain of pregnancy and that this action is enhanced by angiotensin II. To test these hypotheses, we quantified baroreflex control of heart rate in nonpregnant and pregnant conscious rabbits before and after: 1) blockade of NO synthase (NOS) with Nomega-nitro-L-arginine (20 mg/kg iv); 2) blockade of the angiotensin II AT1 receptor with L-158,809 (5 microg x kg(-1) x min(-1) iv); 3) infusion of angiotensin II (1 ng x kg(-1) x min(-1) nonpregnant, 1.6-4 ng x kg(-1) x min(-1) pregnant iv); 4) combined blockade of angiotensin II AT(1) receptors and NOS; and 5) combined infusion of angiotensin II and blockade of NOS. To determine the potential role of brain neuronal NOS (nNOS), mRNA and protein levels were measured in the paraventricular nucleus, nucleus of the solitary tract, caudal ventrolateral medulla, and rostral ventrolateral medulla in pregnant and nonpregnant rabbits. The decrease in baroreflex gain observed in pregnant rabbits (from 23.3 +/- 3.6 to 7.1 +/- 0.9 beats x min(-1) x mmHg(-1), P < 0.05) was not reversed by NOS blockade (to 8.3 +/- 2.5 beats x min(-1) x mmHg(-1)), angiotensin II blockade (to 5.0 +/- 1.1 beats x min(-1) x mmHg(-1)), or combined blockade (to 12.3 +/- 4.8 beats x min(-1) x mmHg(-1)). Angiotensin II infusion with (to 5.7 +/- 1.0 beats x min(-1) x mmHg(-1)) or without (to 8.4 +/- 2.4 beats x min(-1) x mmHg(-1)) NOS blockade also failed to improve baroreflex gain in pregnant or nonpregnant rabbits. In addition, nNOS mRNA and protein levels in cardiovascular brain regions were not different between nonpregnant and pregnant rabbits. Therefore, we conclude that NO, either alone or via an interaction with angiotensin II, is not responsible for decrease in baroreflex gain during pregnancy.
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Affiliation(s)
- Daisy L Daubert
- Oregon Health & Science University, Department of Physiology and Pharmacology, Portland, Oregon 97239, USA
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Benter IF, Yousif MHM, Cojocel C, Al-Maghrebi M, Diz DI. Angiotensin-(1-7) prevents diabetes-induced cardiovascular dysfunction. Am J Physiol Heart Circ Physiol 2007; 292:H666-72. [PMID: 17213482 DOI: 10.1152/ajpheart.00372.2006] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The aim of this study was to test the hypothesis that treatment with angiotensin-(1-7) [ANG-(1-7)] or ANG-(1-7) nonpeptide analog AVE-0991 can produce protection against diabetes-induced cardiovascular dysfunction. We examined the influence of chronic treatment (4 wk) with ANG-(1-7) (576 microg.kg(-1).day(-1) ip) or AVE-0991 (576 microg.kg(-1).day(-1) ip) on proteinuria, vascular responsiveness of isolated carotid and renal artery ring segments and mesenteric bed to vasoactive agonists, and cardiac recovery from ischemia-reperfusion in streptozotocin-treated rats (diabetes). Animals were killed 4 wk after induction of diabetes and/or treatment with ANG-(1-7) or AVE-0991. There was a significant increase in urine protein (231 +/- 2 mg/24 h) in diabetic animals compared with controls (88 +/- 6 mg/24 h). Treatment of diabetic animals with ANG-(1-7) or AVE-0991 resulted in a significant reduction in urine protein compared with vehicle-treated diabetic animals (183 +/- 16 and 149 +/- 15 mg/24 h, respectively). Treatment with ANG-(1-7) or AVE-0991 also prevented the diabetes-induced abnormal vascular responsiveness to norepinephrine, endothelin-1, angiotensin II, carbachol, and histamine in the perfused mesenteric bed and isolated carotid and renal arteries. In isolated perfused hearts, recovery of left ventricular function from 40 min of global ischemia was significantly better in ANG-(1-7)- or AVE-0991-treated animals. These results suggest that activation of ANG-(1-7)-mediated signal transduction could be an important therapeutic strategy to reduce cardiovascular events in diabetic patients.
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Affiliation(s)
- Ibrahim F Benter
- Dept. of Pharmacology and Toxicology, Faculty of Medicine, Kuwait University, P. O. Box 24923, Safat 13110, Kuwait.
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Benter IF, Yousif MHM, Anim JT, Cojocel C, Diz DI. Angiotensin-(1-7) prevents development of severe hypertension and end-organ damage in spontaneously hypertensive rats treated with L-NAME. Am J Physiol Heart Circ Physiol 2006; 290:H684-91. [PMID: 16403946 DOI: 10.1152/ajpheart.00632.2005] [Citation(s) in RCA: 144] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We examined the influence of chronic treatment with ANG-(1-7) on development of hypertension and end-organ damage in spontaneously hypertensive rats (SHR) chronically treated with the nitric oxide synthesis inhibitor L-NAME (SHR-L-NAME). L-NAME administered orally (80 mg/l) for 4 wk significantly elevated mean arterial pressure (MAP) compared with SHR controls drinking regular water (269 +/- 10 vs. 196 +/- 6 mmHg). ANG-(1-7) (24 microg x kg(-1) x h(-1)) or captopril (300 mg/l) significantly attenuated the elevation in MAP due to L-NAME (213 +/- 7 and 228 +/- 8 mmHg, respectively), and ANG-(1-7) + captopril completely reversed the L-NAME-dependent increase in MAP (193 +/- 5 mmHg). L-NAME-induced increases in urinary protein were significantly lower in ANG-(1-7)-treated animals (226 +/- 6 vs. 145 +/- 12 mg/day). Captopril was more effective (96 +/- 12 mg/day), and there was no additional effect of captopril + ANG-(1-7) (87 +/- 5 mg/day). The abnormal vascular responsiveness to endothelin-1, carbachol, and sodium nitroprusside in perfused mesenteric vascular bed of SHR-L-NAME was improved by ANG-(1-7) or captopril, with no additive effect of ANG-(1-7) + captopril. In isolated perfused hearts, recovery of left ventricular function from 40 min of global ischemia was significantly better in ANG-(1-7)- or captopril-treated SHR-L-NAME, with additive effects of combined treatment. The beneficial effects of ANG-(1-7) on MAP and cardiac function were inhibited when indomethacin was administered with ANG-(1-7), but indomethacin did not reverse the protective effects on proteinuria or vascular reactivity. The protective effects of the ANG-(1-7) analog AVE-0991 were qualitatively comparable to those of ANG-(1-7) but were not improved over those of captopril alone. Thus, during reduced nitric oxide availability, ANG-(1-7) attenuates development of severe hypertension and end-organ damage; prostaglandins participate in the MAP-lowering and cardioprotective effects of ANG-(1-7); and additive effects of captopril + ANG-(1-7) on MAP, but not proteinuria or endothelial function, suggest common, as well as different, mechanisms of action for the two treatments. Together, the results provide further evidence of a role for ANG-(1-7) in protective effects of angiotensin-converting enzyme inhibition and suggest dissociation of factors influencing MAP and those influencing end-organ damage.
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Affiliation(s)
- Ibrahim F Benter
- Dept. of Pharmacology and Toxicology, Faculty of Medicine, Kuwait Univ., PO Box 24923, Safat 13110, Kuwait.
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