1
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Kuneš J, Zicha J. Research on Experimental Hypertension in Prague (1966-2009). Physiol Res 2024; 73:S49-S66. [PMID: 39016152 PMCID: PMC11412355 DOI: 10.33549/physiolres.935425] [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: 06/06/2024] [Accepted: 06/14/2024] [Indexed: 09/04/2024] Open
Abstract
The study of ontogenetic aspects of water and electrolyte metabolism performed in the Institute of Physiology (Czechoslovak Academy of Sciences) led to the research on the increased susceptibility of immature rats to salt-dependent forms of hypertension since 1966. Hemodynamic studies in developing rats paved the way to the evaluation of hemodynamic mechanisms during the development of genetic hypertension in SHR. A particular attention was focused on altered renal function and kidney damage in both salt and genetic hypertension with a special respect to renin-angiotensin system. Renal damage associated with hypertension progression was in the center of interest of several research groups in Prague. The alterations in ion transport, cell calcium handling and membrane structure as well as their relationship to abnormal lipid metabolism were studied in a close cooperation with laboratories in Munich, Glasgow, Montreal and Paris. The role of NO and oxidative stress in various forms of hypertension was a subject of a joint research with our Slovak colleagues focused mainly on NO-deficient hypertension elicited by chronic L-NAME administration. Finally, we adopted a method enabling us to evaluate the balance of vasoconstrictor and vasodilator mechanisms in BP maintenance. Using this method we demonstrated sympathetic hyperactivity and relative NO deficiency in rats with either salt-dependent or genetic hypertension. At the end of the first decennium of this century we were ready to modify our traditional approach towards modern trends in the research of experimental hypertension. Keywords: Salt-dependent hypertension o Genetic hypertension o Body fluids o Hemodynamics o Ion transport o Cell membrane structure and function o Renal function o Renin-angiotensin systems.
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Affiliation(s)
- J Kuneš
- Laboratory of Experimental Hypertension, Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic.
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2
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Abstract
Heat stress is described as the cumulative detrimental effect caused by an imbalance between heat production within the body and heat dissipation. When cattle are exposed to heat stress with skin surface temperatures exceeding 35 °C, gene networks within and across cells respond to environmental heat loads with both intra and extracellular signals that coordinate cellular and whole-animal metabolism changes to store heat and rapidly increase evaporative heat loss. In this study, we examined evidence from genes known to be associated with heat tolerance (Hsp70, HSF1, HspB8, SOD1, PRLH, ATP1A1, MTOR, and EIF2AK4). This information could serve as valuable resource material for breeding programs aimed at increasing the thermotolerance of cattle.
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Affiliation(s)
- LuLan Zeng
- College of Life Sciences, Northwest A&F University, Yangling, China
| | - Kaixing Qu
- Yunnan Academy of Grassland and Animal Science, Kunming, China
| | - Jicai Zhang
- Yunnan Academy of Grassland and Animal Science, Kunming, China
| | - Bizhi Huang
- Yunnan Academy of Grassland and Animal Science, Kunming, China
| | - Chuzhao Lei
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, China
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3
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Kasas AHE, Farag IM, Darwish HR, Soliman YA, Nagar EME, Ibrahim MA, Kamel S, Warda M. Molecular characterization of alpha subunit 1 of sodium pump (ATP1A1) gene in Camelus dromedarius: its differential tissue expression potentially interprets the role in osmoregulation. Mol Biol Rep 2022; 49:3849-3861. [PMID: 35235155 DOI: 10.1007/s11033-022-07232-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Accepted: 02/04/2022] [Indexed: 12/19/2022]
Abstract
BACKGROUND Dromedary or one-humped camel (Camelus dromedarius) is distinctively acclimatized to survive the arid conditions of the desert environment. It has an excellent ability to compete dehydration with substantial tolerance for rapid dehydration. Therefore, it offers an excellent model for studying osmoregulation. Molecular characterization of Na+/K+ ATPase as a central regulator of electrolyte normohemostasis affords a better understanding of this mechanism in camel. Here is the first to resolve the full-length of alpha-1 subunit of sodium pump (ATP1A1) gene with its differential expression in dromedary tissues. RESULTS The nucleotide sequence for the recovered full cDNA of ATP1A1was submitted to the GenBank (NCBI GenBank accession #MW628635) and bioinformatically analyzed. The cDNA sequence was of 3760 bp length with an open reading frame (ORF) of 3066 bp encoding a putative 1021 amino acids polypeptide with a molecular mass of 112696 Da. Blast search analysis revealed the shared high similarity of dromedary ATP1A1gene with other known ATP1A1genes in different species. The comparative analysis of its protein sequence confirmed the high identity with other mammalian ATP1A1 proteins. Further transcriptomic investigation for different organs was performed by real-time PCR to compare its level of expression among different organs. The results confirm a direct function between the ATP1A1 gene expression and the order of vital performance of these organs. The expression of ATP1A1 mRNA in the adrenal gland and brain was significantly higher than that in the other organs. The noticed down expression in camel kidney concomitant with overexpression in the adrenal cortex might interpret how dromedary expels access sodium without water loss with relative high ability to restrain mineralocorticoid-induced sodium retention on drinking salty water. CONCLUSION The results reflect the importance of sodium pump in these organs. Na+/K+ ATPase in the adrenal gland and brain than other organs.
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Affiliation(s)
- A H El Kasas
- Department of Cell Biology, National Research Center, Dokki, Giza, 12622, Egypt
| | - I M Farag
- Department of Cell Biology, National Research Center, Dokki, Giza, 12622, Egypt
| | - H R Darwish
- Department of Cell Biology, National Research Center, Dokki, Giza, 12622, Egypt
| | - Y A Soliman
- Central Lab for Evaluation of Veterinary Biologics (CLEVB), Agriculture Research Center (ARC), Cairo, Egypt
| | - E M El Nagar
- Central Lab for Evaluation of Veterinary Biologics (CLEVB), Agriculture Research Center (ARC), Cairo, Egypt
| | - Marwa A Ibrahim
- Department of Biochemistry and Molecular Biology, Faculty of Veterinary Medicine, Cairo University, Giza, 12211, Egypt
| | - Shaimaa Kamel
- Department of Biochemistry and Molecular Biology, Faculty of Veterinary Medicine, Cairo University, Giza, 12211, Egypt
| | - Mohamad Warda
- Department of Biochemistry and Molecular Biology, Faculty of Veterinary Medicine, Cairo University, Giza, 12211, Egypt.
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4
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Isanta-Navarro J, Arnott SE, Klauschies T, Martin-Creuzburg D. Dietary lipid quality mediates salt tolerance of a freshwater keystone herbivore. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 769:144657. [PMID: 33493914 DOI: 10.1016/j.scitotenv.2020.144657] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/13/2020] [Accepted: 12/18/2020] [Indexed: 06/12/2023]
Abstract
Salinization of freshwater ecosystems is a growing hazard for organisms and ecosystem functioning worldwide. In northern latitudes, road salt that is being transported into water bodies can cause year-round increases in lake salinity levels. Exploring the environmental factors driving the susceptibility of freshwater zooplankton to road salt is crucial for assessing the impact of salinization on food web processes. We studied the role of essential lipids, i.e., sterols and long-chain polyunsaturated fatty acids (PUFAs), in mediating salt tolerance of the freshwater keystone herbivore Daphnia. Sterols and PUFAs are involved in regulating ion permeability of biological membranes and thus we hypothesized that the susceptibility to salt is affected by the dietary sterol and PUFA supply. Life history experiments revealed opposing effects of sterol and PUFA supplementation on salt tolerance, i.e., tolerance increased upon sterol supplementation but decreased upon PUFA supplementation, which is consistent with their proposed impact on membrane permeability. Our results suggest that the susceptibility of freshwater zooplankton to salinization strongly depends on the dietary lipid supply and thus the phytoplankton community composition. Hence, trophic state related differences in the phytoplankton community composition need to be considered when assessing the consequences of salinization for freshwater ecosystem functioning.
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Affiliation(s)
- Jana Isanta-Navarro
- Limnological Institute, University of Konstanz, Mainaustrasse 252, 78464 Konstanz, Germany.
| | - Shelley E Arnott
- Department of Biology, Queen's University, 116 Barrie Street, Kingston, ON K7L 3J9, Canada.
| | - Toni Klauschies
- Institute for Biochemistry and Biology, University of Potsdam, Maulbeerallee 2, 14469 Potsdam, Germany.
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5
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Sahoo SS, Mishra C, Rout M, Nayak G, Mohanty ST, Panigrahy KK. Comparative in silico and protein-protein interaction network analysis of ATP1A1 gene. GENE REPORTS 2016. [DOI: 10.1016/j.genrep.2016.10.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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6
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Kashyap N, Kumar P, Deshmukh B, Bhat S, Kumar A, Chauhan A, Bhushan B, Singh G, Sharma D. Association of ATP1A1 gene polymorphism with thermotolerance in Tharparkar and Vrindavani cattle. Vet World 2015; 8:892-7. [PMID: 27047171 PMCID: PMC4774683 DOI: 10.14202/vetworld.2015.892-897] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Revised: 06/13/2015] [Accepted: 06/20/2015] [Indexed: 11/24/2022] Open
Abstract
Aim: One of the major biochemical aspects of thermoregulation is equilibrium of ion gradient across biological membranes. Na+/K+-ATPase, a member of P type-ATPase family, is a major contributor to the mechanism that actively controls cross-membrane ion gradient. Thus, we examined ATP1A1 gene that encodes alpha-1 chain of Na+/K+-ATPase, for genetic polymorphisms. Materials and Methods: A total of 100 Vrindavani (composite cross strain of Hariana x Holstein-Friesian/Brown Swiss/Jersey) and 64 Tharparkar (indigenous) cattle were screened for genetic polymorphism in ATP1A1 gene, using polymerase chain reaction single-strand conformation polymorphism and DNA sequencing. For association studies, rectal temperature (RT) and respiration rate (RR) of all animals were recorded twice daily for 3 seasons. Results: A SNP (C2789A) was identified in exon 17 of ATP1A1 gene. Three genotypes namely CC, CA, and AA were observed in both, Vrindavani and Tharparkar cattle. The gene frequencies in Tharparkar and Vrindavani for allele A were 0.51 and 0.48, and for allele C were 0.49 and 0.52, respectively, which remained at intermediate range. Association study of genotypes with RT and RR in both cattle population revealed that the animals with genotype CC exhibited significantly lower RT and higher heat tolerance coefficient than CA and AA genotypes. Conclusion: Differential thermoregulation between different genotypes of ATP1A1 gene indicate that the ATP1A1 gene could be potentially contributing to thermotolerance in both, Tharparkar, an indigenous breed and Vrindavani, a composite crossbred cattle.
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Affiliation(s)
- Neeraj Kashyap
- Division of Animal Genetics, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Pushpendra Kumar
- Division of Animal Genetics, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Bharti Deshmukh
- Department of Animal Genetics and Breeding, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India
| | - Sandip Bhat
- Division of Animal Genetics, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Amit Kumar
- Division of Animal Genetics, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Anuj Chauhan
- Division of Animal Genetics, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Bharat Bhushan
- Division of Animal Genetics, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Gyanendra Singh
- Division of Physiology and Climatology, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Deepak Sharma
- Division of Animal Genetics, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
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7
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Zicha J, Dobešová Z, Vokurková M, Rauchová H, Hojná S, Kadlecová M, Behuliak M, Vaněčková I, Kuneš J. Age-dependent salt hypertension in Dahl rats: fifty years of research. Physiol Res 2013; 61:S35-S87. [PMID: 22827876 DOI: 10.33549/physiolres.932363] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Fifty years ago, Lewis K. Dahl has presented a new model of salt hypertension - salt-sensitive and salt-resistant Dahl rats. Twenty years later, John P. Rapp has published the first and so far the only comprehensive review on this rat model covering numerous aspects of pathophysiology and genetics of salt hypertension. When we summarized 25 years of our own research on Dahl/Rapp rats, we have realized the need to outline principal abnormalities of this model, to show their interactions at different levels of the organism and to highlight the ontogenetic aspects of salt hypertension development. Our attention was focused on some cellular aspects (cell membrane function, ion transport, cell calcium handling), intra- and extrarenal factors affecting renal function and/or renal injury, local and systemic effects of renin-angiotensin-aldosterone system, endothelial and smooth muscle changes responsible for abnormal vascular contraction or relaxation, altered balance between various vasoconstrictor and vasodilator systems in blood pressure maintenance as well as on the central nervous and peripheral mechanisms involved in the regulation of circulatory homeostasis. We also searched for the age-dependent impact of environmental and pharmacological interventions, which modify the development of high blood pressure and/or organ damage, if they influence the salt-sensitive organism in particular critical periods of development (developmental windows). Thus, severe self-sustaining salt hypertension in young Dahl rats is characterized by pronounced dysbalance between augmented sympathetic hyperactivity and relative nitric oxide deficiency, attenuated baroreflex as well as by a major increase of residual blood pressure indicating profound remodeling of resistance vessels. Salt hypertension development in young but not in adult Dahl rats can be attenuated by preventive increase of potassium or calcium intake. On the contrary, moderate salt hypertension in adult Dahl rats is attenuated by superoxide scavenging or endothelin-A receptor blockade which do not affect salt hypertension development in young animals.
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Affiliation(s)
- J Zicha
- Centre for Cardiovascular Research, Prague, Czech Republic.
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8
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Amaiden MR, Santander VS, Monesterolo NE, Campetelli AN, Rivelli JF, Previtali G, Arce CA, Casale CH. Tubulin pools in human erythrocytes: altered distribution in hypertensive patients affects Na+, K+-ATPase activity. Cell Mol Life Sci 2011; 68:1755-68. [PMID: 20953891 PMCID: PMC11114553 DOI: 10.1007/s00018-010-0549-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Revised: 08/24/2010] [Accepted: 09/15/2010] [Indexed: 12/26/2022]
Abstract
The presence of tubulin in human erythrocytes was demonstrated using five different antibodies. Tubulin was distributed among three operationally distinguishable pools: membrane, sedimentable structure and soluble fraction. It is known that in erythrocytes from hypertensive subjects (HS), the Na(+), K(+)-ATPase (NKA) activity is partially inhibited as compared with erythrocytes from normal subjects (NS). In erythrocytes from HS the membrane tubulin pool is increased by ~150%. NKA was found to be forming a complex with acetylated tubulin that results in inhibition of enzymes. This complex was also increased in erythrocytes from HS. Treatment of erythrocytes from HS with nocodazol caused a decrease of acetylated tubulin in the membrane and stimulation of NKA activity, whereas taxol treatment on erythrocytes from NS had the opposite effect. These results suggest that, in erythrocytes from HS, tubulin was translocated to the membrane, where it associated with NKA with the consequent enzyme inhibition.
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Affiliation(s)
- Marina R. Amaiden
- Departamento de Biología Molecular, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, 5800 Córdoba Argentina
| | - Verónica S. Santander
- Departamento de Biología Molecular, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, 5800 Córdoba Argentina
| | - Noelia E. Monesterolo
- Departamento de Biología Molecular, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, 5800 Córdoba Argentina
| | - Alexis N. Campetelli
- Departamento de Biología Molecular, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, 5800 Córdoba Argentina
| | - Juan F. Rivelli
- Departamento de Biología Molecular, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, 5800 Córdoba Argentina
| | - Gabriela Previtali
- Departamento de Biología Molecular, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, 5800 Córdoba Argentina
| | - Carlos A. Arce
- Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), UNC-CONICET, Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina
| | - César H. Casale
- Departamento de Biología Molecular, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, 5800 Córdoba Argentina
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9
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Savcioglu F, Ozsoy O, Hacioglu G, Kucukatay V, Yargicoglu P, Agar A. The effect of sodium metabisulfite on visual evoked potentials in rats with hypercholesterolemia. Toxicol Mech Methods 2011; 21:479-86. [DOI: 10.3109/15376516.2011.568981] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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10
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Amin MS, Reza E, Wang H, Leenen FH. Sodium Transport in the Choroid Plexus and Salt-Sensitive Hypertension. Hypertension 2009; 54:860-7. [DOI: 10.1161/hypertensionaha.108.125807] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
To elucidate the role of epithelial sodium channels (ENaCs) and Na
+
-K
+
-ATPase in Na
+
transport by the choroid plexus, we studied ENaC expression and Na
+
transport in the choroid plexus. Lateral ventricle choroid plexuses were obtained from young male Wistar, Dahl salt–resistant (SS.BN13), and Dahl salt–sensitive (SS/MCW) rats on a regular (0.3%) or high- (8.0%) salt diet. The effects of ENaC blocker benzamil and Na
+
-K
+
-ATPase blocker ouabain on sodium transport were evaluated by measuring the amounts of retained
22
Na
+
and by evaluating intracellular [Na
+
] with Sodium Green fluorescence. In Wistar rats, ENaC distribution was as follows: microvilli, 10% to 30%; cytoplasm, 60% to 80%; and basolateral membrane, 5% to 10%. Benzamil (10
−8
m
) decreased
22
Na
+
retention by 20% and ouabain (10
−3
m
) increased retention by 40%, whereas ouabain and benzamil combined caused no change. Similar changes were noted in intracellular [Na
+
]. In Dahl rats on a regular salt diet, intracellular [Na
+
] was similar, but the amount of retained
22
Na
+
was less in sensitive versus resistant rats. High salt did not affect ENaC mRNA or protein, nor the benzamil induced decreases in retained
22
Na
+
or intracellular [Na
+
] in either strain. However, high salt increased intracellular [Na
+
] and attenuated the increase in uptake of
22
Na
+
by ouabain in resistant but not sensitive rats, suggesting a decrease in Na
+
-K
+
-ATPase activity only in resistant rats. These findings suggest that both ENaC and Na
+
-K
+
-ATPase regulate Na
+
transport in the choroid plexus. Aberrant regulation of Na
+
transport and of Na
+
-K
+
-ATPase activity, but not of ENaCs, might contribute to the increase in cerebrospinal fluid [Na
+
] in Dahl salt-sensitive rats on a high-salt diet.
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Affiliation(s)
- Md Shahrier Amin
- From the Hypertension Unit (M.S.A., E.R., H.W., F.H.H.L.), University of Ottawa Heart Institute, Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.S.A., E.R., F.H.H.L.), University of Ottawa, Ottawa, Ontario, Canada
| | - Erona Reza
- From the Hypertension Unit (M.S.A., E.R., H.W., F.H.H.L.), University of Ottawa Heart Institute, Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.S.A., E.R., F.H.H.L.), University of Ottawa, Ottawa, Ontario, Canada
| | - Hongwei Wang
- From the Hypertension Unit (M.S.A., E.R., H.W., F.H.H.L.), University of Ottawa Heart Institute, Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.S.A., E.R., F.H.H.L.), University of Ottawa, Ottawa, Ontario, Canada
| | - Frans H.H. Leenen
- From the Hypertension Unit (M.S.A., E.R., H.W., F.H.H.L.), University of Ottawa Heart Institute, Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.S.A., E.R., F.H.H.L.), University of Ottawa, Ottawa, Ontario, Canada
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11
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Mokry M, Cuppen E. The Atp1a1 gene from inbred Dahl salt sensitive rats does not contain the A1079T missense transversion. Hypertension 2008; 51:922-7. [PMID: 18285611 DOI: 10.1161/hypertensionaha.107.108415] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The existence of the A1079T transversion in the alpha1 isoform of the Na(+), K(+)-ATPase (Atp1a1) gene in Dahl salt-sensitive rat (SS/Jr) strain, discovered by Herrera and Ruiz-Opazo and proposed to underlay hypertension sensitivity, represents one of the most controversial topics in hypertension research. As our research group did not have any previous connection to any party in this dispute nor to hypertension-related research, we were asked (J Hypertens. 2006;24:2312-2313) to definitively adjudge the existence of the A1079T transversion. Hence, different state-of-the art SNP detection technologies that depend on a variety of mechanisms and enzymes to detect the transversion in genomic DNA as well as cDNA derived from different tissues were used. Although it was possible to readily detect other silent polymorphisms between SS and SR strains in the Atp1a1 gene by all methods used, no evidence for the existence of the A1079T transversion in SS/Jr rats was found.
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Affiliation(s)
- Michal Mokry
- Hubrecht Institute, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
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12
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Park IS, Kang YH, Kang JS. Effects of taurine on plasma and liver lipids, erythrocyte ouabain sensitive Na efflux and platelet aggregation in Sprague Dawley rats. Nutr Res Pract 2007; 1:200-5. [PMID: 20368939 PMCID: PMC2849023 DOI: 10.4162/nrp.2007.1.3.200] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2007] [Revised: 09/01/2007] [Accepted: 09/14/2007] [Indexed: 12/02/2022] Open
Abstract
The effects of taurine on plasma and liver cholesterol, erythrocyte ouabain sensitive Na efflux and platelet aggregation were examined in Sprague Dawley rats fed control or 0.5% cholesterol with 0.2% cholate diet. Plasma and liver levels of total cholesterol were increased significantly (p<0.05) in rats fed cholesterol diet compared to the control, and taurine significantly decreased the elevated plasma level of cholesterol in rats fed cholesterol diet (p<0.05). HDL-cholesterol was decreased in groups fed the cholesterol diet regardless of taurine supplementation and the difference between groups with and without cholesterol was significant (p<0.01). Plasma triglyceride was decreased and liver triglyceride was increased both significantly (p<0.05) in rats fed cholesterol compared to the control. Plasma and liver triglyceride in rats fed taurine was decreased significantly compared to the control (p<0.05). Intracellular Na tended to be lower in rats fed cholesterol or taurine and higher in rats fed cholesterol plus taurine compared to the control. Na efflux through Na-K ATPase and the passive leak of Na was somewhat reduced in rats fed cholesterol or taurine and was augmented in rats fed cholesterol plus taurine compared to the control, which showed a similar trend to the intracellular Na. Taurine supplementation caused a suppression of Na efflux in groups fed control diet and restored the suppressed Na efflux in groups fed cholesterol. Platelet aggregation was significantly decreased in the group fed taurine compared to the control (p<0.05) and the group fed cholesterol plus taurine was also a little lower in aggregation than the group fed cholesterol. Microscopic examination showed that taurine prevented fatty liver in rats fed cholesterol diet. Taurine known for stimulating Na-K ATPase in some cell types rather decreased erythrocyte ouabain sensitive Na-K ATPase in the present study. Taurine had hypolipidemic and hypocholesterolemic effects and inhibited platelet aggregation which may be favorable for prevention of cardiovascular diseases.
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Affiliation(s)
- In Sun Park
- Department of Foods & Nutrition, Cheju National University, Cheju 690-756, Korea
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13
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Harris EL, Barnard R. A1079T transversion in the gene for the α1 isophorm of the Na+/K+ ATPase in the Dahl S rat. J Hypertens 2006; 24:1209-10; author reply 1210-3. [PMID: 16685223 DOI: 10.1097/01.hjh.0000226213.41678.52] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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14
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15
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Vokurková M, Nováková O, Dobesová Z, Kunes J, Zicha J. Relationships between membrane lipids and ion transport in red blood cells of Dahl rats. Life Sci 2005; 77:1452-64. [PMID: 15936778 DOI: 10.1016/j.lfs.2005.03.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2004] [Accepted: 03/31/2005] [Indexed: 10/25/2022]
Abstract
Distinct changes of membrane lipid content could contribute to the abnormalities of ion transport that take part in the development of salt hypertension in Dahl rats. The relationships between lipid content and particular ion transport systems were studied in red blood cells (RBC) of Dahl rats kept on low- and high-salt diets for 5 weeks since weaning. Dahl salt-sensitive (SS/Jr) rats on high-salt diet had increased blood pressure, levels of plasma triacylglycerols and total plasma cholesterol compared to salt-resistant (SR/Jr) rats. Furthermore, RBC of SS/Jr rats differed from SR/Jr ones by increased content of total membrane phospholipids, but membrane cholesterol was not changed significantly. SS/Jr rats had higher RBC intracellular Na+ (Na(i)+) content and enhanced bumetanide-sensitive Rb+ uptake. RBC membrane content of cholesterol and phospholipids correlated positively with RBC Na(i)+ content, with the activity of Na+-K+ pump and Na+-K+-2Cl- cotransport and also with Rb+ leak. The content of phosphatidylserines plus phosphatidylinositols was positively associated with RBC Na(i)+ content, with the activity of Na+-K+ pump and Na+-K+-2Cl- cotransport and with Rb+ leak. The content of sphingomyelins was positively related to Na+-K+-2Cl- cotransport activity and negatively to ouabain-sensitive Rb+-K+ exchange. We can conclude that observed relationships between ion transport and the membrane content of cholesterol and/or sphingomyelins, which are known to regulate membrane fluidity, might participate in the pathogenesis of salt hypertension in Dahl rats.
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Affiliation(s)
- Martina Vokurková
- Institute of Physiology, Academy of Sciences of the Czech Republic and Cardiovascular Research Center, Prague, Czech Republic.
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16
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Kaneko Y, Cloix JF, Herrera VL, Ruiz-Opazo N. Corroboration of Dahl S Q276L alpha1Na,K-ATPase protein sequence: impact on affinities for ligands and on E1 conformation. J Hypertens 2005; 23:745-52. [PMID: 15775778 DOI: 10.1097/01.hjh.0000163142.89835.c7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Multifactorial analyses support the hypothesis that alpha1Na,K-ATPase is a hypertension susceptibility gene in Dahl S rats. However, two studies report non-detection of the A1079T transversion underlying the Q276L substitution in Dahl S alpha1Na,K-ATPase questioning the validity of ATP1A1 as a hypertension susceptibility gene. To resolve this discordance, we investigated the issue at the protein level. DESIGN AND METHODS We employed protein blot analysis using Q276L- and Q276-specific; antipeptide-specific antibodies; tested differential chymotrypsin cleavage efficiency, measured differential Na and K affinities of alpha1Na,K-ATPases in Dahl S and Dahl R renal membranes and determined amino acid sequences of purified Dahl S alpha1Na,K-ATPase chymotryptic-digest peptides. RESULTS We detected Q276L variant protein in Dahl S rats; and Q276 wild-type variant in Dahl R, spontaneously hypertensive (SHR), Lewis and Wistar-Kyoto (WKY) rat kidney membranes. Q276L variant exhibits less chymotrypsin cleavage efficiency than the Q276 wild-type variant, consistent with the substitution of hydrophobic L for hydrophilic Q. Kinetic studies of kidney membranes detect increased Na affinity and decreased K affinity in renal Dahl S alpha1Na,K-ATPase compared with Dahl R. Protein sequencing of high pressure liquid chromatography (HPLC)-purified chymotrypsin digested 77 kDa peptide confirms Q276L substitution in the Dahl S alpha1Na,K-ATPase. CONCLUSIONS Data demonstrate the existence and functional significance of the Q276L variant in Dahl S rats.
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Affiliation(s)
- Yuji Kaneko
- Section of Molecular Medicine, Department of Medicine, Boston University School of Medicine, 700 Albany Street, W-609, Boston, Massachusetts 02118, USA
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17
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Kaneko Y, Herrera VLM, Didishvili T, Ruiz-Opazo N. Sex-specific effects of dual ET-1/ANG II receptor (Dear) variants in Dahl salt-sensitive/resistant hypertension rat model. Physiol Genomics 2005; 20:157-64. [PMID: 15561758 DOI: 10.1152/physiolgenomics.00108.2004] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Essential (polygenic) hypertension is a complex genetic disorder that remains a major risk factor for cardiovascular disease despite clinical advances, reiterating the need to elucidate molecular genetic mechanisms. Elucidation of susceptibility genes remains a challenge, however. Blood pressure (BP) regulatory pathways through angiotensin II (ANG II) and endothelin-1 (ET-1) receptor systems comprise a priori candidate susceptibility pathways. Here we report that the dual ET-1/ANG II receptor gene ( Dear) is structurally and functionally distinct between Dahl salt-sensitive, hypertensive (S) and salt-resistant, normotensive (R) rats. The Dahl S S44/M74 variant is identical to the previously reported Dear cDNA with equivalent affinities for both ET-1 and ANG II, in contrast to Dahl R S44P/M74T variant, which exhibits absent ANG II binding but effective ET-1 binding. The S44P substitution localizes to the ANG II-binding domain predicted by the molecular recognition theory, providing compelling support of this theory. The Dear gene maps to rat chromosome 2 and cosegregates with BP in female F2(R×S) intercross rats with highly significant linkage (LOD 3.61) accounting for 14% of BP variance, but not in male F2(R×S) intercross rats. Altogether, the data suggest the hypothesis that modification of the critical balance between ANG II and ET-1 systems through variant Dear contributes to hypertension susceptibility in female F2(R×S) intercross rats. Further investigations are necessary to corroborate genetic linkage through congenic rat studies, to investigate putative gene interactions, and to show causality by transgenesis and/or intervention. More importantly, the data reiterate the importance of sex-specific factors in hypertension susceptibility.
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Affiliation(s)
- Yuji Kaneko
- Section Molecular Medicine, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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18
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Filigheddu F, Troffa C, Argiolas G, Pinna Parpaglia P, Glorioso N. The ??1Na,K-AtPase Locus Plays an Additive Role in Na,K Pump Rate Modulation with Respect to the ??-Adducin Gene in Essential Hypertension. High Blood Press Cardiovasc Prev 2004. [DOI: 10.2165/00151642-200411040-00002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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Vokurková M, Dobesová Z, Pechánová O, Kunes J, Zicha J. Erythrocyte ion transport and membrane lipid composition in young and adult rats with NO-deficient hypertension. Life Sci 2003; 73:1637-44. [PMID: 12875896 DOI: 10.1016/s0024-3205(03)00486-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The aim of our study was to search for abnormalities of sodium and potassium transport in erythrocytes of male Wistar rats subjected to chronic L-NAME treatment (40 mg/kg/day) for 4 weeks either from weaning (4-week-old) or in adulthood (12-week-old). Sodium content, Na(+),K(+)-pump and Na(+),K(+)-cotransport activity, cation leaks as well as membrane cholesterol and phospholipid contents were determined in fresh erythrocytes. Chronic inhibition of NO synthase elicited similar blood pressure rise in both age groups which did not differ in the degree of NO synthase inhibition. No significant ion transport abnormalities were disclosed in erythrocytes of young NO-deficient rats, whereas erythrocyte Na(+) content, outward Na(+),K(+)-cotransport and inward Na(+) leak were significantly reduced in adult hypertensive animals compared to age-matched controls. It should be noted that the erythrocytes of adult control rats were characterized by higher activity of Na(+),K(+)-pump and Na(+),K(+)-cotransport, increased Na(+) and Rb(+) leaks and elevated membrane cholesterol content compared to those of young normotensive controls. Increased Na(+) leak and elevated membrane cholesterol content but reduced membrane phospholipid content were revealed in erythrocytes of adult hypertensive rats when compared to young hypertensive rats. It can be concluded that young and adult Wistar rats did not differ in the extent of NO synthase inhibition and blood pressure rise elicited by chronic L-NAME treatment. Our results exclude the important participation of classical sodium transport abnormalities in the pathogenesis of this NO-deficient form of experimental hypertension.
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Affiliation(s)
- Martina Vokurková
- Center for Experimental Cardiovascular Research, Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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20
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Vokurková M, Dobesová Z, Kunes J, Zicha J. Membrane ion transport in erythrocytes of salt hypertensive Dahl rats and their F2 hybrids: the importance of cholesterol. Hypertens Res 2003; 26:397-404. [PMID: 12887131 DOI: 10.1291/hypres.26.397] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The possible association of salt hypertension and altered lipid metabolism with abnormalities of particular systems transporting sodium and potassium has been studied in erythrocytes of Dahl rats and their F2 hybrids fed a high-salt diet since weaning. Our attention was paid to the Na(+)-K+ pump, Na(+)-K+ cotransport and especially to passive membrane permeability for Na+ and Rb+ (Na+ and Rb+ leak), because the Na+ leak was found to be dependent on the genotype, age and salt intake of Dahl rats, whereas the Rb+ leak was suggested to be a potential marker of salt sensitivity in Dahl and Sabra rats. Young male Dahl salt-sensitive (SS/Jr) and salt-resistant (SR/Jr) rats kept on a low-salt (0.3% NaCl) or high-salt diet (8% NaCl) were used for the progenitor study. The subsequent genetic study was based on 135 young male SS/Jr x SR/Jr F2 hybrids fed a high-salt diet since weaning. Ouabain (5 mmol/l) and bumetanide (10 micromol/l) were used to distinguish the contribution of the Na(+)-K+ pump, Na(+)-K+ cotransport and passive membrane permeability to measured net Na+ fluxes and unidirectional Rb+ (K+) movements. Compared to normotensive SR/Jr animals, salt-loaded SS/Jr rats had higher blood pressure (BP), elevated erythrocyte Na+ content, and increased Na+ and Rb+ leaks together with enhanced Na+ and Rb+ transport mediated by the Na(+)-K+ pump and Na(+)-K+ cotransport system. Salt hypertensive Dahl rats were also characterized by elevated plasma levels of total cholesterol and triglycerides, which were positively associated with BP of F2 hybrids (r=0.27 and 0.24, p< 0.01). In F2 hybrids, mean arterial pressure correlated significantly with erythrocyte Na+ content (r=0.24, p<0.01) and ouabain-sensitive Na+ extrusion, but not with the passive membrane permeability for Na+ or Rb+ (r=-0.02 and 0.06, not significant). Both of the above-mentioned significant associations could partially be ascribed to the dependence of erythrocyte Na+ content and ouabain-sensitive Na+ extrusion on plasma cholesterol (r=0.18 and 0.21, p<0.05). Our results support the idea that abnormal lipid metabolism and/or altered Na+,K(+)-ATPase function play an important role in the pathogenesis of salt hypertension in salt-sensitive Dahl rats.
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Affiliation(s)
- Martina Vokurková
- Institute of Physiology, Academy of Sciences of the Czech Republic, Center for Experimental Research of Cardiovascular Diseases, Prague, Czech Republic
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21
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Orlov SN, Dutil J, Hamet P, Deng AY. Replacement of (alpha)1-Na-K-ATPase of Dahl rats by Milan rats lowers blood pressure but does not affect its activity. Physiol Genomics 2001; 7:171-7. [PMID: 11773603 DOI: 10.1152/physiolgenomics.00059.2001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Both linkage and use of congenic strains have shown that a chromosome region near the gene for the Na-K-ATPase alpha(1)-subunit (Atp1a1) contained a quantitative trait locus (QTL) for blood pressure (BP). Currently, two congenic strains, designated S.M5 and S.M6, were made by replacing a segment of the Dahl salt-sensitive SS/Jr (S) rat by the homologous region of the Milan normotensive rat (MNS). In S.M5, the gene for Atp1a1 is from the MNS strain; whereas in S.M6, Atp1a1 is from the S strain. The baseline activity of the alpha(1)-Na-K-ATPase and its stoichiometry were evaluated by an assay of ouabain-sensitive inwardly and outwardly directed (86)Rb and (22)Na fluxes in erythrocytes. The two congenic strains showed a similar BP, but both had a BP lower than that of S rats (P < 0.0001). Neither the alpha(1)-Na-K-ATPase activity nor its stoichiometry was affected by the substitution of the Atp1a1 alleles of S by those of MNS. Thus the BP-lowering effects observed in S.M5 and S.M6 could not be attributed to the alpha(1)-Na-K-ATPase activity or its stoichiometry. Atp1a1 is not supported as a candidate to be a BP QTL.
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Affiliation(s)
- S N Orlov
- Research Centre, Centre Hospitalier de l'Université de Montreal, Hôtel Dieu, Montreal, Quebec, H2W 1T8, Canada
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