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Rodrigues AF, Todiras M, Qadri F, Alenina N, Bader M. Angiotensin deficient FVB/N mice are normotensive. Br J Pharmacol 2023; 180:1843-1861. [PMID: 36740662 DOI: 10.1111/bph.16051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 01/17/2023] [Accepted: 01/31/2023] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND AND PURPOSE All previous rodent models lacking the peptide hormone angiotensin II (Ang II) were hypotensive. A mixed background strain with global deletion of the angiotensinogen gene was backcrossed to the FVB/N background (Agt-KO), a strain preferred for transgenic generation. Surprisingly, the resulting line turned out to be normotensive. Therefore, this study aimed to understand the unique blood pressure regulation of FVB/N mice without angiotensin peptides. EXPERIMENTAL APPROACH Acute and chronic recordings of blood pressure (BP) in freely-moving adult mice were performed to establish baseline BP. The pressure responses to sympatholytic and sympathomimetic as well as a nitric oxide inhibitor and donor compounds were used to quantify the neurogenic tone and endothelial function. The role of the renal nerves on baseline BP maintenance was tested by renal denervation. Finally, further phenotyping was done by gene expression analysis, histology and measurement of metabolites in plasma, urine and tissues. KEY RESULTS Baseline BP in adult FVB/N Agt-KO was unexpectedly unaltered. As compensatory mechanisms Agt-KO presented an increased sympathetic nerve activity and reduced endothelial nitric oxide production. However, FVB/N Agt-KO exhibited the renal morphological and physiological alterations previously found in mice lacking the production of Ang II including polyuria and hydronephrosis. The hypotensive effect of bilateral renal denervation was blunted in Agt-KO compared to wildtype FVB/N mice. CONCLUSION AND IMPLICATIONS We describe a germline Agt-KO line that challenges all previous knowledge on BP regulation in mice with deletion of the classical RAS. This line may represent a model of drug-resistant hypertension because it lacks hypotension.
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Affiliation(s)
- André Felipe Rodrigues
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- Department of Biology, Chemistry and Pharmacy, Free University of Berlin, Berlin, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Berlin, Berlin, Germany
| | - Mihail Todiras
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- Nicolae Testemițanu State University of Medicine and Pharmacy, Chisinau, Moldova
| | - Fatimunnisa Qadri
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Natalia Alenina
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Berlin, Berlin, Germany
| | - Michael Bader
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Berlin, Berlin, Germany
- Charité Universitätsmedizin Berlin, Berlin, Germany
- Institute for Biology, University of Lübeck, Lübeck, Germany
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2
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Daghbouche-Rubio N, López-López JR, Pérez-García MT, Cidad P. Vascular smooth muscle ion channels in essential hypertension. Front Physiol 2022; 13:1016175. [PMID: 36213221 PMCID: PMC9540222 DOI: 10.3389/fphys.2022.1016175] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 08/31/2022] [Indexed: 11/13/2022] Open
Abstract
Hypertension is a highly prevalent chronic disease and the major risk factor for cardiovascular diseases, the leading cause of death worldwide. Hypertension is characterized by an increased vascular tone determined by the contractile state of vascular smooth muscle cells that depends on intracellular calcium levels. The interplay of ion channels determine VSMCs membrane potential and thus intracellular calcium that controls the degree of contraction, vascular tone and blood pressure. Changes in ion channels expression and function have been linked to hypertension, but the mechanisms and molecular entities involved are not completely clear. Furthermore, the literature shows discrepancies regarding the contribution of different ion channels to hypertension probably due to differences both in the vascular preparation and in the model of hypertension employed. Animal models are essential to study this multifactorial disease but it is also critical to know their characteristics to interpret properly the results obtained. In this review we summarize previous studies, using the hypertensive mouse (BPH) and its normotensive control (BPN), focused on the identified changes in the expression and function of different families of ion channels. We will focus on L-type voltage-dependent Ca2+ channels (Cav1.2), canonical transient receptor potential channels and four different classes of K+ channels: voltage-activated (Kv), large conductance Ca2+-activated (BK), inward rectifiers (Kir) and ATP-sensitive (KATP) K+ channels. We will describe the role of these channels in hypertension and we will discuss the importance of integrating individual changes in a global context to understand the complex interplay of ion channels in hypertension.
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3
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Li S, Phillips JK. Patient Selection for Renal Denervation in Hypertensive Patients: What Makes a Good Candidate? Vasc Health Risk Manag 2022; 18:375-386. [PMID: 35592729 PMCID: PMC9113553 DOI: 10.2147/vhrm.s270182] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 04/22/2022] [Indexed: 01/03/2023] Open
Affiliation(s)
- Sheran Li
- Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Guangzhou, People’s Republic of China
- Correspondence: Sheran Li, Department of Emergency Medicine, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 West Yanjiang Road, Yuexiu District, Guangzhou, Guangdong Province, 510120, People’s Republic of China, Tel +86 20 81332723, Fax +86 20 8133 2650, Email
| | - Jacqueline K Phillips
- Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
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4
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Junho CVC, Trentin-Sonoda M, Panico K, Dos Santos RSN, Abrahão MV, Vernier ICS, Fürstenau CR, Carneiro-Ramos MS. Cardiorenal syndrome: long road between kidney and heart. Heart Fail Rev 2022. [PMID: 35133552 DOI: 10.1007/s10741-022-10218-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/24/2022] [Indexed: 12/16/2022]
Abstract
Almost 200 years ago, the first evidence described by Robert Bright (1836) showed the strong interaction between the kidneys and heart and, since then, the scientific community has dedicated itself to better understanding the mechanisms involved in the kidney-heart relationship, known in recent decades as cardiorenal syndrome (CRS). This syndrome includes a wide clinical variety that affects the kidneys and heart, in an acute or chronic manner. Moreover, it is well established in the literature that the immune system, the sympathetic nervous system, the renin-angiotensin-aldosterone, and the oxidative stress actively play a strong role in the cellular and molecular processes present in CRS. More recently, uremic molecules and epigenetic factors have been also shown to be key mediators in the development of syndrome. The present review intends to present the state of the art regarding CRS and to show the paths known, until now, in the long road between the kidneys and heart.
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5
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Jama HA, Muralitharan RR, Xu C, O'Donnell JA, Bertagnolli M, Broughton BRS, Head GA, Marques FZ. Rodent models of hypertension. Br J Pharmacol 2021; 179:918-937. [PMID: 34363610 DOI: 10.1111/bph.15650] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/02/2021] [Accepted: 03/03/2021] [Indexed: 01/03/2023] Open
Abstract
Elevated blood pressure (BP), or hypertension, is the main risk factor for cardiovascular disease. As a multifactorial and systemic disease that involves multiple organs and systems, hypertension remains a challenging disease to study. Models of hypertension are invaluable to support the discovery of the specific genetic, cellular and molecular mechanisms underlying essential hypertension, as well as to test new possible treatments to lower BP. Rodent models have proven to be an invaluable tool for advancing the field. In this review, we discuss the strengths and weaknesses of rodent models of hypertension through a systems approach. We highlight the ways how target organs and systems including the kidneys, vasculature, the sympathetic nervous system (SNS), immune system and the gut microbiota influence BP in each rodent model. We also discuss often overlooked hypertensive conditions such as pulmonary hypertension and hypertensive-pregnancy disorders, providing an important resource for researchers.
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Affiliation(s)
- Hamdi A Jama
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia.,Heart Failure Research Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Rikeish R Muralitharan
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia.,Institute for Medical Research, Ministry of Health Malaysia, Kuala Lumpur, Malaysia
| | - Chudan Xu
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia
| | - Joanne A O'Donnell
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia
| | - Mariane Bertagnolli
- Laboratory of Maternal-child Health, Hospital Sacre-Coeur Research Center, CIUSSS Nord-de-l'Île-de-Montréal, Montreal, Canada.,School of Physical and Occupational Therapy, Faculty of Medicine, McGill University, Montreal, Canada
| | - Bradley R S Broughton
- Department of Pharmacology, Biomedicine Discovery Institute, Faculty of Medicine Nursing and Health Sciences, Monash University, Melbourne, Australia
| | - Geoffrey A Head
- Department of Pharmacology, Biomedicine Discovery Institute, Faculty of Medicine Nursing and Health Sciences, Monash University, Melbourne, Australia.,Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Francine Z Marques
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia.,Heart Failure Research Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
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6
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Sones JL, Yarborough CC, O'Besso V, Lemenze A, Douglas NC. Genotypic analysis of the female BPH/5 mouse, a model of superimposed preeclampsia. PLoS One 2021; 16:e0253453. [PMID: 34270549 DOI: 10.1371/journal.pone.0253453] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 06/04/2021] [Indexed: 11/19/2022] Open
Abstract
Animal models that recapitulate human diseases and disorders are widely used to investigate etiology, diagnosis, and treatment of those conditions in people. Disorders during pregnancy are particularly difficult to explore as interventions in pregnant women are not easily performed. Therefore, models that allow for pre-conception investigations are advantageous for elucidating the mechanisms involved in adverse pregnancy outcomes that are responsible for both maternal and fetal morbidity, such as preeclampsia. The Blood Pressure High (BPH)/5 mouse model has been used extensively to study the pathogenesis of preeclampsia. The female BPH/5 mouse is obese with increased adiposity and borderline hypertension, both of which are exacerbated with pregnancy making it a model of superimposed preeclampsia. Thus, the BPH/5 model shares traits with a large majority of women with pre-existing conditions that predisposes them to preeclampsia. We sought to explore the genome of the BPH/5 female mouse and determine the genetic underpinnings that may contribute to preeclampsia-associated phenotypes in this model. Using a whole genome sequencing approach, we are the first to characterize the genetic mutations in BPH/5 female mice that make it unique from the closely related BPH/2 model and the normotensive background strain, C57Bl/6. We found the BPH/5 female mouse to be uniquely different from BPH/2 and C57Bl/6 mice with a genetically complex landscape. The majority of non-synonymous consequences within the coding region of BPH/5 females were missense mutations found most abundant on chromosome X when comparing BPH/5 and BPH/2, and on chromosome 8 when comparing BPH/5 to C57Bl/6. Genetic mutations in BPH/5 females largely belong to immune system-related processes, with overlap between BPH/5 and BPH/2 models. Further studies examining each gene mutation during pregnancy are warranted to determine key contributors to the BPH/5 preeclamptic-like phenotype and to identify genetic similarities to women that develop preeclampsia.
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7
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Li S, Hildreth CM, Rahman AA, Barton SA, Wyse BF, Lim CK, Pilowsky PM, Phillips JK. Renal denervation does not affect hypertension or the renin-angiotensin system in a rodent model of juvenile-onset polycystic kidney disease: clinical implications. Sci Rep 2021; 11:14286. [PMID: 34253766 PMCID: PMC8275789 DOI: 10.1038/s41598-021-93575-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 06/21/2021] [Indexed: 12/17/2022] Open
Abstract
We examined the effect of total and afferent renal denervation (RDN) on hypertension and the renin-angiotensin system (RAS) in a rodent model of juvenile-onset polycystic kidney disease (PKD). Lewis Polycystic Kidney (LPK) and control rats received total, afferent or sham RDN by periaxonal application of phenol, capsaicin or normal saline, respectively, and were monitored for 4-weeks. Afferent RDN did not affect systolic blood pressure (SBP) determined by radiotelemetry in either strain (n = 19) while total RDN significantly reduced SBP in Lewis rats 4-weeks post-denervation (total vs. sham, 122 ± 1 vs. 130 ± 2 mmHg, P = 0.002, n = 25). Plasma and kidney renin content determined by radioimmunoassay were significantly lower in LPK vs. Lewis (plasma: 278.2 ± 6.7 vs. 376.5 ± 11.9 ng Ang I/ml/h; kidney: 260.1 ± 6.3 vs. 753.2 ± 37.9 ng Ang I/mg/h, P < 0.001, n = 26). These parameters were not affected by RDN. Intrarenal mRNA expression levels of renin, angiotensinogen, angiotensin-converting enzyme (ACE)2, and angiotensin II receptor type 1a were significantly lower, whereas ACE1 expression was significantly higher in the LPK vs. Lewis (all P < 0.05, n = 26). This pattern of intrarenal RAS expression was not changed by RDN. In conclusion, RDN does not affect hypertension or the RAS in the LPK model and indicates RDN might not be a suitable antihypertensive strategy for individuals with juvenile-onset PKD.
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Affiliation(s)
- Sheran Li
- Department of Biomedical Sciences, Faculty of Medicine, Human and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Cara M Hildreth
- Department of Biomedical Sciences, Faculty of Medicine, Human and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Ahmed A Rahman
- Department of Biomedical Sciences, Faculty of Medicine, Human and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Sean A Barton
- Department of Biomedical Sciences, Faculty of Medicine, Human and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Benjamin F Wyse
- Department of Biomedical Sciences, Faculty of Medicine, Human and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Chai K Lim
- Department of Biomedical Sciences, Faculty of Medicine, Human and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Paul M Pilowsky
- Discipline of Physiology, School of Medical Sciences, University of Sydney, Sydney, Australia
| | - Jacqueline K Phillips
- Department of Biomedical Sciences, Faculty of Medicine, Human and Health Sciences, Macquarie University, Sydney, NSW, 2109, Australia.
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8
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Abstract
Increasing studies strongly prove that renal denervation, a minimally invasive surgery, is a promising new non-drug treatment method that can effectively control blood pressure in patients with resistant hypertension, but the evaluation of the long-term blood pressure control effect of renal denervation for resistant hypertension is still lacking. Here, we critically review current long-term follow-up data about the use of renal denervation for RH to comprehensively evaluate the effectiveness of renal denervation for RH, and to provide practical guidance for practitioners who are establishing a renal denervation service. Limited by the current research, many problems need to be solved before renal denervation is applied to RH. In addition, ambulatory blood pressure should be the first choice for the evaluation of blood pressure. Finally, the continuous antihypertensive effect of renal denervation in different renal denervation systems also needs to be strictly compared.
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Affiliation(s)
- Bo Liang
- Nanjing University of Chinese Medicine, Nanjing, China
| | - Yi Liang
- Southwest Medical University, Luzhou, China
| | - Rui Li
- Nanjing University of Chinese Medicine, Nanjing, China
| | - Ning Gu
- Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese Medicine, Nanjing, China.
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9
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Asirvatham-Jeyaraj N, Gauthier MM, Banek CT, Ramesh A, Garver H, Fink GD, Osborn JW. Renal Denervation and Celiac Ganglionectomy Decrease Mean Arterial Pressure Similarly in Genetically Hypertensive Schlager (BPH/2J) Mice. Hypertension 2021; 77:519-528. [PMID: 33390041 PMCID: PMC7803455 DOI: 10.1161/hypertensionaha.119.14069] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Supplemental Digital Content is available in the text. Renal denervation (RDNX) lowers mean arterial pressure (MAP) in patients with resistant hypertension. Less well studied is the effect of celiac ganglionectomy (CGX), a procedure which involves the removal of the nerves innervating the splanchnic vascular bed. We hypothesized that RDNX and CGX would both lower MAP in genetically hypertensive Schlager (BPH/2J) mice through a reduction in sympathetic tone. Telemeters were implanted into the femoral artery in mice to monitor MAP before and after RDNX (n=5), CGX (n=6), or SHAM (n=6). MAP, systolic blood pressure, diastolic blood pressure, and heart rate were recorded for 14 days postoperatively. The MAP response to hexamethonium (10 mg/kg, IP) was measured on control day 3 and postoperative day 10 as a measure of global neurogenic pressor activity. The efficacy of denervation was assessed by measurement of tissue norepinephrine. Control MAP was similar among the 3 groups before surgical treatments (≈130 mm Hg). On postoperative day 14, MAP was significantly lower in RDNX (−11±2 mm Hg) and CGX (−11±1 mm Hg) groups compared with their predenervation values. This was not the case in SHAM mice (−5±3 mm Hg). The depressor response to hexamethonium in the RDNX group was significantly smaller on postoperative day 10 (−10±5 mm Hg) compared with baseline control (−25±10 mm Hg). This was not the case in mice in the SHAM (day 10; −28±5 mm Hg) or CGX (day 10; −34±7 mm Hg) group. In conclusion, both renal and splanchnic nerves contribute to hypertension in BPH/2J mice, but likely through different mechanisms.
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Affiliation(s)
- Ninitha Asirvatham-Jeyaraj
- From the Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis (M.M.G., C.T.B., A.R., J.W.O.).,Department of Biotechnology, Indian Institute of Technology Madras, Chennai (N.A.-J.)
| | | | - Christopher T Banek
- From the Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis (M.M.G., C.T.B., A.R., J.W.O.).,Department of Physiology, University of Arizona, Tucson (M.M.G., C.T.B.)
| | - Abhismitha Ramesh
- From the Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis (M.M.G., C.T.B., A.R., J.W.O.)
| | - Hannah Garver
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing (H.G., G.D.F.)
| | - Gregory D Fink
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing (H.G., G.D.F.)
| | - John W Osborn
- From the Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis (M.M.G., C.T.B., A.R., J.W.O.)
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10
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Jackson KL, Gueguen C, Lim K, Eikelis N, Stevenson ER, Charchar FJ, Lambert GW, Burke SL, Paterson MR, Marques FZ, Head GA. Neural suppression of miRNA-181a in the kidney elevates renin expression and exacerbates hypertension in Schlager mice. Hypertens Res 2020; 43:1152-1164. [PMID: 32427944 DOI: 10.1038/s41440-020-0453-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/05/2020] [Accepted: 04/14/2020] [Indexed: 11/09/2022]
Abstract
BPH/2J mice are a genetic model of hypertension with overactivity of the sympathetic nervous system (SNS) and renin-angiotensin system (RAS). BPH/2J display higher renal renin mRNA and low levels of its negative regulator microRNA-181a (miR-181a). We hypothesise that high renal SNS activity may reduce miR-181a expression, which contributes to elevated RAS activity and hypertension in BPH/2J. Our aim was to determine whether in vivo administration of a renal-specific miR-181a mimic or whether renal denervation could increase renal miR-181a abundance to reduce renal renin mRNA, RAS activity and hypertension in BPH/2J mice. Blood pressure (BP) in BPH/2J and normotensive BPN/3J mice was measured via radiotelemetry probes. Mice were administered miR-181a mimic or a negative control (1-25 nmol, i.v., n = 6-10) with BP measured for 48 h after each dose or they underwent renal denervation or sham surgery (n = 7-9). Injection of 5-25 nmol miR-181a mimic reduced BP in BPH/2J mice after 36-48 h (-5.3 ± 1.8, -6.1 ± 1.9 mmHg, respectively, P < 0.016). Treatment resulted in lower renal renin and inflammatory marker (TLR4) mRNA levels in BPH/2J. The mimic abolished the hypotensive effect of blocking the RAS with enalaprilat (P < 0.01). No differences between mimic or vehicle were observed in BPN/3J mice except for a higher level of renal angiotensinogen in the mimic-treated mice. Renal miR-181a levels that were lower in sham BPH/2J mice were greater following renal denervation and were thus similar to those of BPN/3J. Our findings suggest that the reduced renal miR-181a may partially contribute to the elevated BP in BPH/2J mice, through an interaction between the renal sympathetic nerves and miR-181a regulation of the RAS.
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Affiliation(s)
- Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Cindy Gueguen
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Kyungjoon Lim
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Department of Physiology, Anatomy & Microbiology, School of Life Sciences, La Trobe University, Melbourne, VIC, Australia
| | - Nina Eikelis
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Emily R Stevenson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Fadi J Charchar
- Faculty of Science and Technology, Federation University Australia, Ballarat, VIC, Australia
| | - Gavin W Lambert
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Sandra L Burke
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Madeleine R Paterson
- Hypertension Research Laboratory, School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Francine Z Marques
- Faculty of Science and Technology, Federation University Australia, Ballarat, VIC, Australia.,Hypertension Research Laboratory, School of Biological Sciences, Monash University, Clayton, VIC, Australia.,Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia. .,Department of Pharmacology, Monash University, Clayton, VIC, Australia.
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11
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Jackson KL, Head GA, Gueguen C, Stevenson ER, Lim K, Marques FZ. Mechanisms Responsible for Genetic Hypertension in Schlager BPH/2 Mice. Front Physiol 2019; 10:1311. [PMID: 31681017 PMCID: PMC6813185 DOI: 10.3389/fphys.2019.01311] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 09/30/2019] [Indexed: 01/18/2023] Open
Abstract
It has been 45 years since Gunther Schlager used a cross breeding program in mice to develop inbred strains with high, normal, and low blood pressure (BPH/2, BPN/3, and BPL/1 respectively). Thus, it is timely to gather together the studies that have characterized and explored the mechanisms associated with the hypertension to take stock of exactly what is known and what remains to be determined. Growing evidence supports the notion that the mechanism of hypertension in BPH/2 mice is predominantly neurogenic with some of the early studies showing aberrant brain noradrenaline levels in BPH/2 compared with BPN/3. Analysis of the adrenal gland using microarray suggested an association with the activity of the sympathetic nervous system. Indeed, in support of this, there is a larger depressor response to ganglion blockade, which reduced blood pressure in BPH/2 mice to the same level as BPN/3 mice. Greater renal tyrosine hydroxylase staining and greater renal noradrenaline levels in BPH/2 mice suggest sympathetic hyperinnervation of the kidney. Renal denervation markedly reduced the blood pressure in BPH/2 but not BPN/3 mice, confirming the importance of renal sympathetic nervous activity contributing to the hypertension. Further, there is an important contribution to the hypertension from miR-181a and renal renin in this strain. BPH/2 mice also display greater neuronal activity of amygdalo-hypothalamic cardiovascular regulatory regions. Lesions of the medial nucleus of the amygdala reduced the hypertension in BPH/2 mice and abolished the strain difference in the effect of ganglion blockade, suggesting a sympathetic mechanism. Further studies suggest that aberrant GABAergic inhibition may play a role since BPH/2 mice have low GABAA receptor δ, α4 and β2 subunit mRNA expression in the hypothalamus, which are predominantly involved in promoting tonic neuronal inhibition. Allopregnanolone, an allosteric modulator of GABAA receptors, which increase the expression of these subunits in the amygdala and hypothalamus, is shown to reduce the hypertension and sympathetic nervous system contribution in BPH/2 mice. Thus far, evidence suggests that BPH/2 mice have aberrant GABAergic inhibition, which drives neuronal overactivity within amygdalo-hypothalamic brain regions. This overactivity is responsible for the greater sympathetic contribution to the hypertension in BPH/2 mice, thus making this an ideal model of neurogenic hypertension.
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Affiliation(s)
- Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Cindy Gueguen
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Emily R Stevenson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Kyungjoon Lim
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Department of Physiology, Anatomy and Microbiology, School of Life Sciences, La Trobe University, Melbourne, VIC, Australia
| | - Francine Z Marques
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Hypertension Research Laboratory, School of Biological Sciences, Monash University, Clayton, VIC, Australia
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12
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Carlström M, Braga VA. Mechanisms underlying the effects of renal denervation in renovascular hypertension. Hypertens Res 2019; 42:754-757. [PMID: 30796370 DOI: 10.1038/s41440-019-0233-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 01/27/2019] [Accepted: 01/28/2019] [Indexed: 12/25/2022]
Affiliation(s)
- Mattias Carlström
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Valdir A Braga
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden. .,Biotechnology Center, Federal University of Paraiba, Joao Pessoa-PB, Brazil.
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