1
|
Lauar MR, Almutlaq RN, Guntipally S, Anidu B, Kram R, Ross J, Osborn JW, Dayton A, Evans LC. Removing interoceptive input from the kidney to the brain reduces salt appetite in DOCA hypertensive rats. Kidney Int 2024:S0085-2538(24)00695-1. [PMID: 39370041 DOI: 10.1016/j.kint.2024.08.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 07/24/2024] [Accepted: 08/08/2024] [Indexed: 10/08/2024]
Affiliation(s)
- Mariana R Lauar
- Department of Surgery, University of Minnesota, Minneapolis, Minnesota, USA
| | - Rawan N Almutlaq
- Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis, Minnesota, USA
| | | | - Babatunde Anidu
- Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Rachel Kram
- Department of Surgery, University of Minnesota, Minneapolis, Minnesota, USA
| | - Jaryd Ross
- Department of Surgery, University of Minnesota, Minneapolis, Minnesota, USA
| | - John W Osborn
- Department of Surgery, University of Minnesota, Minneapolis, Minnesota, USA
| | - Alex Dayton
- Division of Nephrology and Hypertension, University of Minnesota, Minneapolis, Minnesota, USA
| | - Louise C Evans
- Department of Surgery, University of Minnesota, Minneapolis, Minnesota, USA.
| |
Collapse
|
2
|
Evans LC, Dayton A, Osborn JW. Renal nerves in physiology, pathophysiology and interoception. Nat Rev Nephrol 2024:10.1038/s41581-024-00893-3. [PMID: 39363020 DOI: 10.1038/s41581-024-00893-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/27/2024] [Indexed: 10/05/2024]
Abstract
Sympathetic efferent renal nerves have key roles in the regulation of kidney function and blood pressure. Increased renal sympathetic nerve activity is thought to contribute to hypertension by promoting renal sodium retention, renin release and renal vasoconstriction. This hypothesis led to the development of catheter-based renal denervation (RDN) for the treatment of hypertension. Two RDN devices that ablate both efferent and afferent renal nerves received FDA approval for this indication in 2023. However, in animal models, selective ablation of afferent renal nerves resulted in comparable anti-hypertensive effects to ablation of efferent and afferent renal nerves and was associated with a reduction in sympathetic nerve activity. Selective afferent RDN also improved kidney function in a chronic kidney disease model. Notably, the beneficial effects of RDN extend beyond hypertension and chronic kidney disease to other clinical conditions that are associated with elevated sympathetic nerve activity, including heart failure and arrhythmia. These findings suggest that the kidney is an interoceptive organ, as increased renal sensory nerve activity modulates sympathetic activity to other organs. Future studies are needed to translate this knowledge into novel therapies for the treatment of hypertension and other cardiorenal diseases.
Collapse
Affiliation(s)
- Louise C Evans
- Department of Surgery, University of Minnesota, Minneapolis, MN, USA
| | - Alex Dayton
- Division of Nephrology and Hypertension, University of Minnesota, Minneapolis, MN, USA
| | - John W Osborn
- Department of Surgery, University of Minnesota, Minneapolis, MN, USA.
| |
Collapse
|
3
|
Evans LC, Dailey-Krempel B, Lauar MR, Dayton A, Vulchanova L, Osborn JW. Renal interoception in health and disease. Auton Neurosci 2024; 255:103208. [PMID: 39128142 DOI: 10.1016/j.autneu.2024.103208] [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: 04/17/2024] [Revised: 07/19/2024] [Accepted: 07/26/2024] [Indexed: 08/13/2024]
Abstract
Catheter based renal denervation has recently been FDA approved for the treatment of hypertension. Traditionally, the anti-hypertensive effects of renal denervation have been attributed to the ablation of the efferent sympathetic renal nerves. In recent years the role of the afferent sensory renal nerves in the regulation of blood pressure has received increased attention. In addition, afferent renal denervation is associated with reductions in sympathetic nervous system activity. This suggests that reductions in sympathetic drive to organs other than the kidney may contribute to the non-renal beneficial effects observed in clinical trials of catheter based renal denervation. In this review we will provide an overview of the role of the afferent renal nerves in the regulation of renal function and the development of pathophysiologies, both renal and non-renal. We will also describe the central projections of the afferent renal nerves, to give context to the responses seen following their ablation and activation. Finally, we will discuss the emerging role of the kidney as an interoceptive organ. We will describe the potential role of the kidney in the regulation of interoceptive sensitivity and in this context, speculate on the possible pathological consequences of altered renal function.
Collapse
Affiliation(s)
- Louise C Evans
- Department of Surgery, University of Minnesota Medical School, Minneapolis 55455, United States of America
| | - Brianna Dailey-Krempel
- Department of Neuroscience, University of Minnesota, Minneapolis 55455, United States of America
| | - Mariana R Lauar
- Department of Surgery, University of Minnesota Medical School, Minneapolis 55455, United States of America
| | - Alex Dayton
- Division of Nephrology and Hypertension, University of Minnesota Medical School, Minneapolis 55455, United States of America
| | - Lucy Vulchanova
- Department of Neuroscience, University of Minnesota, Minneapolis 55455, United States of America
| | - John W Osborn
- Department of Surgery, University of Minnesota Medical School, Minneapolis 55455, United States of America.
| |
Collapse
|
4
|
Herring N, Ajijola OA, Foreman RD, Gourine AV, Green AL, Osborn J, Paterson DJ, Paton JFR, Ripplinger CM, Smith C, Vrabec TL, Wang HJ, Zucker IH, Ardell JL. Neurocardiology: translational advancements and potential. J Physiol 2024. [PMID: 39340173 DOI: 10.1113/jp284740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Accepted: 09/03/2024] [Indexed: 09/30/2024] Open
Abstract
In our original white paper published in the The Journal of Physiology in 2016, we set out our knowledge of the structural and functional organization of cardiac autonomic control, how it remodels during disease, and approaches to exploit such knowledge for autonomic regulation therapy. The aim of this update is to build on this original blueprint, highlighting the significant progress which has been made in the field since and major challenges and opportunities that exist with regard to translation. Imbalances in autonomic responses, while beneficial in the short term, ultimately contribute to the evolution of cardiac pathology. As our understanding emerges of where and how to target in terms of actuators (including the heart and intracardiac nervous system (ICNS), stellate ganglia, dorsal root ganglia (DRG), vagus nerve, brainstem, and even higher centres), there is also a need to develop sensor technology to respond to appropriate biomarkers (electrophysiological, mechanical, and molecular) such that closed-loop autonomic regulation therapies can evolve. The goal is to work with endogenous control systems, rather than in opposition to them, to improve outcomes.
Collapse
Affiliation(s)
- N Herring
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - O A Ajijola
- UCLA Neurocardiology Research Center of Excellence, David Geffen School of Medicine, Los Angeles, CA, USA
| | - R D Foreman
- Department of Biochemistry and Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - A V Gourine
- Centre for Cardiovascular and Metabolic Neuroscience, University College London, London, UK
| | - A L Green
- Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK
| | - J Osborn
- Department of Surgery, University of Minnesota, Minneapolis, MN, USA
| | - D J Paterson
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - J F R Paton
- Manaaki Manawa - The Centre for Heart Research, Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - C M Ripplinger
- Department of Pharmacology, University of California Davis, Davis, CA, USA
| | - C Smith
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH, USA
| | - T L Vrabec
- Department of Physical Medicine and Rehabilitation, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - H J Wang
- Department of Anesthesiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - I H Zucker
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - J L Ardell
- UCLA Neurocardiology Research Center of Excellence, David Geffen School of Medicine, Los Angeles, CA, USA
| |
Collapse
|
5
|
Hu W, Tu H, Wadman MC, Li YL, Zhang D. Renal denervation achieves its antiarrhythmic effect through attenuating macrophage activation and neuroinflammation in stellate ganglia in chronic heart failure. Cardiovasc Res 2024:cvae196. [PMID: 39321201 DOI: 10.1093/cvr/cvae196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 05/22/2024] [Accepted: 09/23/2024] [Indexed: 09/27/2024] Open
Abstract
AIMS Renal denervation (RDN) is widely investigated in multiple studies of sympathetically driven cardiovascular diseases. While the therapeutic potential of RDN for ventricular arrhythmia has been reported, the mechanisms responsible for its antiarrhythmic effect are poorly understood. Our recent study showed that macrophage expansion-induced neuroinflammation in the stellate ganglion (SG) was a critical factor for cardiac sympathetic overactivation and ventricular arrhythmogenesis in chronic heart failure (CHF). This study investigates if and how RDN decreases ventricular arrhythmias by attenuating neuroinflammation in cardiac sympathetic postganglionic (CSP) neurons in CHF. METHODS AND RESULTS Rat CHF was induced by surgical ligation of the left anterior descending coronary artery (LAD). At 12 weeks after LAD ligation, completed bilateral RDN was achieved by surgically cutting all the visible renal nerves around the renal artery and vein, followed by applying of 70% ethanol around the vessels. Immunofluorescence staining and Western blot data showed that expression of granulocyte-macrophage colony-stimulating factor (GM-CSF) and its receptor-α subunit (GM-CSFRα) in SGs was increased in CHF rats. RDN not only reduced CHF-elevated GM-CSF levels in kidney, serum and SGs, but also attenuated macrophage expansion and neuroinflammation in SGs from CHF rats. Using flow cytometry, we confirmed that RDN reduced the percentage of macrophages in SGs, which is pathologically increased in CHF. RDN also decreased CHF-enhanced N-type Ca2+ currents in CSP neurons and attenuated CHF-elevated cardiac sympathetic nerve activity. ECG data from 24-hour continuous telemetry recording in conscious rats revealed that RDN improved CHF-induced heterogeneity of ventricular electrical activities and reduced the duration of spontaneous ventricular tachyarrhythmias in CHF rats. CONCLUSIONS RDN alleviates cardiac sympathetic overactivation and ventricular arrhythmogenesis through attenuating GM-CSF-induced macrophage activation and neuroinflammation within SGs in CHF. This suggests that manipulation of the GM-CSF signaling pathway could be a novel strategy for achieving the antiarrhythmic effect of RDN in CHF.
Collapse
Affiliation(s)
- Wenfeng Hu
- Department of Emergency Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Huiyin Tu
- Department of Emergency Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Michael C Wadman
- Department of Emergency Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Yu-Long Li
- Department of Emergency Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Department of Cellular & Integrative Physiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Dongze Zhang
- Department of Emergency Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| |
Collapse
|
6
|
Baumann D, Van Helden D, Evans LC, Vulchanova L, Dayton A, Osborn JW. IL-1R Mediated Activation of Renal Sensory Nerves in DOCA-Salt Hypertension. Hypertension 2024; 81:1811-1821. [PMID: 38841853 PMCID: PMC11254549 DOI: 10.1161/hypertensionaha.123.22620] [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: 12/19/2023] [Accepted: 05/20/2024] [Indexed: 06/07/2024]
Abstract
BACKGROUND Clinical trials of renal denervation for the treatment of hypertension have shown a variety of off-target improvements in conditions associated with sympathetic overactivity. This may be due to the ablation of sympathoexcitatory afferent renal nerves, which are overactive under conditions of renal inflammation. Renal IL (interleukin)-1β is elevated in the deoxycorticosterone acetate-salt model of hypertension, and its activity may be responsible for the elevation in afferent renal nerve activity and arterial pressure. METHODS Continuous blood pressure recording of deoxycorticosterone acetate-salt mice with IL-1R (IL-1 receptor) knockout or antagonism was used individually and combined with afferent renal denervation (ARDN) to assess mechanistic overlap. Protein quantification and histological analysis of kidneys were performed to characterize renal inflammation. RESULTS ARDN attenuated deoxycorticosterone acetate-salt hypertension (-20±2-Δmm Hg mean arterial pressure [MAP] relative to control at study end) to a similar degree as total renal denervation (-21±2-Δmm Hg MAP), IL-1R knockout (-16±4-Δmm Hg MAP), or IL-1R antagonism (-20±3-Δmm Hg MAP). The combination of ARDN with knockout (-18±2-Δmm Hg MAP) or antagonism (-19±4-Δmm Hg MAP) did not attenuate hypertension any further than ARDN alone. IL-1R antagonism was found to have an acute depressor effect (-15±3-Δmm Hg MAP, day 10) in animals with intact renal nerves but not those with ARDN. CONCLUSIONS These findings suggest that IL-1R signaling is partially responsible for the elevated afferent renal nerve activity, which stimulates central sympathetic outflow to drive deoxycorticosterone acetate-salt hypertension.
Collapse
Affiliation(s)
- Daniel Baumann
- Graduate Program in Integrative Biology and Physiology (D.B.), University of Minnesota, Minneapolis
- Department of Surgery (D.B., D.V.H., L.C.E., J.W.O.), University of Minnesota, Minneapolis
| | - Dusty Van Helden
- Department of Surgery (D.B., D.V.H., L.C.E., J.W.O.), University of Minnesota, Minneapolis
| | - Louise C Evans
- Department of Surgery (D.B., D.V.H., L.C.E., J.W.O.), University of Minnesota, Minneapolis
| | - Lucy Vulchanova
- Department of Neuroscience (L.V.), University of Minnesota, Minneapolis
| | - Alex Dayton
- Division of Nephrology and Hypertension (A.D.), University of Minnesota, Minneapolis
| | - John W Osborn
- Department of Surgery (D.B., D.V.H., L.C.E., J.W.O.), University of Minnesota, Minneapolis
| |
Collapse
|
7
|
Katsurada K, Patel KP. The role of afferent renal nerves in regulating sympathetic outflow via central nervous system mechanisms. Hypertens Res 2024; 47:1978-1980. [PMID: 38632458 DOI: 10.1038/s41440-024-01677-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Accepted: 03/20/2024] [Indexed: 04/19/2024]
Affiliation(s)
- Kenichi Katsurada
- Division of Cardiovascular Medicine, Department of Internal Medicine, Jichi Medical University School of Medicine, Shimotsuke, Tochigi, Japan.
- Division of Clinical Pharmacology, Department of Pharmacology, Jichi Medical University School of Medicine, Shimotsuke, Tochigi, Japan.
| | - Kaushik P Patel
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, USA
| |
Collapse
|
8
|
Abdulla MH, AlMarabeh S, Bolger T, Lucking EF, O'Halloran KD, Johns EJ. Effects of intrarenal pelvic infusion of tumour necrosis factor-α and interleukin 1-β on reno-renal reflexes in anaesthetised rats. J Hypertens 2024; 42:1027-1038. [PMID: 38690904 DOI: 10.1097/hjh.0000000000003689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2024]
Abstract
OBJECTIVE Reno-renal reflexes are disturbed in cardiovascular and hypertensive conditions when elevated levels of pro-inflammatory mediators/cytokines are present within the kidney. We hypothesised that exogenously administered inflammatory cytokines tumour necrosis factor alpha (TNF-α) and interleukin (IL)-1β modulate the renal sympatho-excitatory response to chemical stimulation of renal pelvic sensory nerves. METHODS In anaesthetised rats, intrarenal pelvic infusions of vehicle [0.9% sodium chloride (NaCl)], TNF-α (500 and 1000 ng/kg) and IL-1β (1000 ng/kg) were maintained for 30 min before chemical activation of renal pelvic sensory receptors was performed using randomized intrarenal pelvic infusions of hypertonic NaCl, potassium chloride (KCl), bradykinin, adenosine and capsaicin. RESULTS The increase in renal sympathetic nerve activity (RSNA) in response to intrarenal pelvic hypertonic NaCl was enhanced during intrapelvic TNF-α (1000 ng/kg) and IL-1β infusions by almost 800% above vehicle with minimal changes in mean arterial pressure (MAP) and heart rate (HR). Similarly, the RSNA response to intrarenal pelvic adenosine in the presence of TNF-α (500 ng/kg), but not IL-1β, was almost 200% above vehicle but neither MAP nor HR were changed. There was a blunted sympatho-excitatory response to intrapelvic bradykinin in the presence of TNF-α (1000 ng/kg), but not IL-1β, by almost 80% below vehicle, again without effect on either MAP or HR. CONCLUSION The renal sympatho-excitatory response to renal pelvic chemoreceptor stimulation is modulated by exogenous TNF-α and IL-1β. This suggests that inflammatory mediators within the kidney can play a significant role in modulating the renal afferent nerve-mediated sympatho-excitatory response.
Collapse
Affiliation(s)
- Mohammed H Abdulla
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork, Cork, Ireland
| | - Sara AlMarabeh
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Biopharmaceutics and Clinical Pharmacy, School of Pharmacy, The University of Jordan, Amman, Jordan
| | - Tom Bolger
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork, Cork, Ireland
| | - Eric F Lucking
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork, Cork, Ireland
| | - Ken D O'Halloran
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork, Cork, Ireland
| | - Edward J Johns
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork, Cork, Ireland
| |
Collapse
|
9
|
Esler MD, Osborn JW, Schlaich MP. Sympathetic Pathophysiology in Hypertension Origins: The Path to Renal Denervation. Hypertension 2024; 81:1194-1205. [PMID: 38557153 DOI: 10.1161/hypertensionaha.123.21715] [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] [Indexed: 04/04/2024]
Abstract
The importance of the sympathetic nervous system in essential hypertension has been recognized in 2 eras. The first was in early decades of the 20th century, through to the 1960s. Here, the sympathetic nervous system was identified as a target for the treatment of hypertension, and an extensive range of antiadrenergic therapies were developed. Then, after a period of lapsed interest, in a second era from 1985 on, the development of precise measures of human sympathetic nerve firing and transmitter release allowed demonstration of the importance of neural mechanisms in the initiation and maintenance of the arterial blood pressure elevation in hypertension. This led to the development of a device treatment of hypertension, catheter-based renal denervation, which we will discuss.
Collapse
Affiliation(s)
- Murray D Esler
- Human Neurotransmitter Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia (M.D.E., M.P.S.)
| | - John W Osborn
- Department of Surgery, Medical School, University of Minnesota, Minneapolis (J.W.O.)
| | - Markus P Schlaich
- Human Neurotransmitter Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia (M.D.E., M.P.S.)
- Dobney Hypertension Centre, Medical School, Royal Perth Hospital Unit and RPH Research Foundation, The University of Western Australia (M.P.S.)
| |
Collapse
|
10
|
Guzik TJ, Nosalski R, Maffia P, Drummond GR. Immune and inflammatory mechanisms in hypertension. Nat Rev Cardiol 2024; 21:396-416. [PMID: 38172242 DOI: 10.1038/s41569-023-00964-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/20/2023] [Indexed: 01/05/2024]
Abstract
Hypertension is a global health problem, with >1.3 billion individuals with high blood pressure worldwide. In this Review, we present an inflammatory paradigm for hypertension, emphasizing the crucial roles of immune cells, cytokines and chemokines in disease initiation and progression. T cells, monocytes, macrophages, dendritic cells, B cells and natural killer cells are all implicated in hypertension. Neoantigens, the NLRP3 inflammasome and increased sympathetic outflow, as well as cytokines (including IL-6, IL-7, IL-15, IL-18 and IL-21) and a high-salt environment, can contribute to immune activation in hypertension. The activated immune cells migrate to target organs such as arteries (especially the perivascular fat and adventitia), kidneys, the heart and the brain, where they release effector cytokines that elevate blood pressure and cause vascular remodelling, renal damage, cardiac hypertrophy, cognitive impairment and dementia. IL-17 secreted by CD4+ T helper 17 cells and γδ T cells, and interferon-γ and tumour necrosis factor secreted by immunosenescent CD8+ T cells, exert crucial effector roles in hypertension, whereas IL-10 and regulatory T cells are protective. Effector mediators impair nitric oxide bioavailability, leading to endothelial dysfunction and increased vascular contractility. Inflammatory effector mediators also alter renal sodium and water balance and promote renal fibrosis. These mechanisms link hypertension with obesity, autoimmunity, periodontitis and COVID-19. A comprehensive understanding of the immune and inflammatory mechanisms of hypertension is crucial for safely and effectively translating the findings to clinical practice.
Collapse
Affiliation(s)
- Tomasz J Guzik
- Centre for Cardiovascular Sciences, University of Edinburgh, Edinburgh, UK.
- Department of Medicine and Omicron Medical Genomics Laboratory, Jagiellonian University, Collegium Medicum, Kraków, Poland.
- Africa-Europe Cluster of Research Excellence (CoRE) in Non-Communicable Diseases & Multimorbidity, African Research Universities Alliance ARUA & The Guild, Glasgow, UK.
| | - Ryszard Nosalski
- Centre for Cardiovascular Sciences, University of Edinburgh, Edinburgh, UK
| | - Pasquale Maffia
- Africa-Europe Cluster of Research Excellence (CoRE) in Non-Communicable Diseases & Multimorbidity, African Research Universities Alliance ARUA & The Guild, Glasgow, UK
- School of Infection & Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
- Department of Pharmacy, School of Medicine and Surgery, University of Naples Federico II, Naples, Italy
| | - Grant R Drummond
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Melbourne, Victoria, Australia
- Centre for Cardiovascular Biology and Disease Research, La Trobe University, Melbourne, Victoria, Australia
| |
Collapse
|
11
|
Shinohara K. Renal denervation in patients with chronic kidney disease: an approach using CO 2 angiography. Hypertens Res 2024; 47:1431-1433. [PMID: 38467794 DOI: 10.1038/s41440-024-01635-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 02/18/2024] [Indexed: 03/13/2024]
Affiliation(s)
- Keisuke Shinohara
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan.
| |
Collapse
|
12
|
Collister JP, Fritcher N, Nahey D. Role of the median preoptic nucleus in the development of chronic deoxycorticosterone acetate (DOCA)-salt hypertension. Physiol Rep 2024; 12:e16046. [PMID: 38749925 PMCID: PMC11096131 DOI: 10.14814/phy2.16046] [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: 11/10/2023] [Revised: 04/18/2024] [Accepted: 04/28/2024] [Indexed: 05/18/2024] Open
Abstract
We have previously reported that the subfornical organ (SFO) does not contribute to the chronic hypertensive response to DOCA-salt in rats, and yet the organum vasculosum of the lamina terminalis (OVLT) plays a significant role in the development of deoxycorticosterone acetate (DOCA)-salt hypertension. Since efferent fibers of the OVLT project to and through the median preoptic nucleus (MnPO), the present study was designed to test the hypothesis that the MnPO is necessary for DOCA-salt hypertension in the rat. Male Sprague-Dawley rats underwent SHAM (MnPOsham; n = 5) or electrolytic lesion of the MnPO (MnPOx; n = 7) followed by subsequent unilateral nephrectomy and telemetry instrumentation. After recovery and during the experimental protocol, rats consumed a 0.1% NaCl diet and 0.9% NaCl drinking solution. Mean arterial pressure (MAP) was recorded telemetrically 5 days before and 21 days after DOCA implantation (100 mg/rat; SQ). The chronic pressor response to DOCA was attenuated in MnPOx rats by Day 11 of treatment and continued such that MAP increased 25 ± 3 mmHg in MnPOsham rats by Day 21 of DOCA compared to 14 ± 3 mmHg in MnPOx rats. These results support the hypothesis that the MnPO is an important brain site of action and necessary for the full development of DOCA-salt hypertension in the rat.
Collapse
Affiliation(s)
- John P. Collister
- Department of Veterinary and Biomedical Sciences, College of Veterinary MedicineUniversity of MinnesotaSt. PaulMinnesotaUSA
| | - Nora Fritcher
- Department of Veterinary and Biomedical Sciences, College of Veterinary MedicineUniversity of MinnesotaSt. PaulMinnesotaUSA
| | - David Nahey
- Department of Veterinary and Biomedical Sciences, College of Veterinary MedicineUniversity of MinnesotaSt. PaulMinnesotaUSA
| |
Collapse
|
13
|
N’Guetta PEY, McLarnon SR, Tassou A, Geron M, Shirvan S, Hill RZ, Scherrer G, O’Brien LL. Comprehensive mapping of sensory and sympathetic innervation of the developing kidney. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.11.15.567276. [PMID: 38496522 PMCID: PMC10942422 DOI: 10.1101/2023.11.15.567276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
The kidney functions as a finely tuned sensor to balance body fluid composition and filter out waste through complex coordinated mechanisms. This versatility requires tight neural control, with innervating efferent nerves playing a crucial role in regulating blood flow, glomerular filtration rate, water and sodium reabsorption, and renin release. In turn sensory afferents provide feedback to the central nervous system for the modulation of cardiovascular function. However, the cells targeted by sensory afferents and the physiological sensing mechanisms remain poorly characterized. Moreover, how the kidney is innervated during development to establish these functions remains elusive. Here, we utilized a combination of light-sheet and confocal microscopy to generate anatomical maps of kidney sensory and sympathetic nerves throughout development and resolve the establishment of functional crosstalk. Our analyses revealed that kidney innervation initiates at embryonic day (E)13.5 as the nerves associate with vascular smooth muscle cells and follow arterial differentiation. By E17.5 axonal projections associate with kidney structures such as glomeruli and tubules and the network continues to expand postnatally. These nerves are synapsin I-positive, highlighting ongoing axonogenesis and the potential for functional crosstalk. We show that sensory and sympathetic nerves innervate the kidney concomitantly and classify the sensory fibers as calcitonin gene related peptide (CGRP)+, substance P+, TRPV1+, and PIEZO2+, establishing the presence of PIEZO2 mechanosensory fibers in the kidney. Using retrograde tracing, we identified the primary dorsal root ganglia, T10-L2, from which PIEZO2+ sensory afferents project to the kidney. Taken together our findings elucidate the temporality of kidney innervation and resolve the identity of kidney sympathetic and sensory nerves.
Collapse
Affiliation(s)
- Pierre-Emmanuel Y. N’Guetta
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Sarah R. McLarnon
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Adrien Tassou
- Department of Cell Biology and Physiology, UNC Neuroscience Center, Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Matan Geron
- Department of Cell Biology and Physiology, UNC Neuroscience Center, Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Sepenta Shirvan
- Department of Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA, USA 92037
| | - Rose Z. Hill
- Department of Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA, USA 92037
| | - Grégory Scherrer
- Department of Cell Biology and Physiology, UNC Neuroscience Center, Department of Pharmacology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; New York Stem Cell Foundation – Robertson Investigator, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Lori L. O’Brien
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| |
Collapse
|
14
|
Benjamin JI, Pollock DM. Current perspective on circadian function of the kidney. Am J Physiol Renal Physiol 2024; 326:F438-F459. [PMID: 38134232 PMCID: PMC11207578 DOI: 10.1152/ajprenal.00247.2023] [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: 08/17/2023] [Revised: 11/28/2023] [Accepted: 12/18/2023] [Indexed: 12/24/2023] Open
Abstract
Behavior and function of living systems are synchronized by the 24-h rotation of the Earth that guides physiology according to time of day. However, when behavior becomes misaligned from the light-dark cycle, such as in rotating shift work, jet lag, and even unusual eating patterns, adverse health consequences such as cardiovascular or cardiometabolic disease can arise. The discovery of cell-autonomous molecular clocks expanded interest in regulatory systems that control circadian physiology including within the kidney, where function varies along a 24-h cycle. Our understanding of the mechanisms for circadian control of physiology is in the early stages, and so the present review provides an overview of what is known and the many gaps in our current understanding. We include a particular focus on the impact of eating behaviors, especially meal timing. A better understanding of the mechanisms guiding circadian function of the kidney is expected to reveal new insights into causes and consequences of a wide range of disorders involving the kidney, including hypertension, obesity, and chronic kidney disease.
Collapse
Affiliation(s)
- Jazmine I Benjamin
- Section of Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - David M Pollock
- Section of Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| |
Collapse
|
15
|
Perrotta S, Carnevale D. Brain-Splenic Immune System Interactions in Hypertension: Cellular and Molecular Mechanisms. Arterioscler Thromb Vasc Biol 2024; 44:65-75. [PMID: 37942610 DOI: 10.1161/atvbaha.123.318230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 10/20/2023] [Indexed: 11/10/2023]
Abstract
Hypertension represents a major worldwide cause of death and disability, and it is becoming increasingly clear that available therapies are not sufficient to reduce the risk of major cardiovascular events. Various mechanisms contribute to blood pressure increase: neurohormonal activation, autonomic nervous system imbalance, and immune activation. Of note, the brain is an important regulator of blood pressure levels; it recognizes the peripheral perturbation and organizes a reflex response by modulating immune system and hormonal release to attempt at restoring the homeostasis. The connection between the brain and peripheral organs is mediated by the autonomic nervous system, which also modulates immune and inflammatory responses. Interestingly, an increased autonomic nervous system activity has been correlated with an altered immune response in cardiovascular diseases. The spleen is the largest immune organ exerting a potent influence on the cardiovascular system during disease and is characterized by a dense noradrenergic innervation. Taken together, these aspects led to hypothesize a key role of neuroimmune mechanisms in the onset and progression of hypertension. This review discusses how the nervous and splenic immune systems interact and how the mechanisms underlying the neuroimmune cross talk influence the disease progression.
Collapse
Affiliation(s)
- Sara Perrotta
- Department of Angiocardioneurology and Translational Medicine, Unit of Neuro and Cardiovascular Pathophysiology, IRCCS (Istituto di Ricovero e Cura a Carattere Scientifico) Neuromed, Pozzilli, Italy (S.P., D.C.)
| | - Daniela Carnevale
- Department of Angiocardioneurology and Translational Medicine, Unit of Neuro and Cardiovascular Pathophysiology, IRCCS (Istituto di Ricovero e Cura a Carattere Scientifico) Neuromed, Pozzilli, Italy (S.P., D.C.)
- Department of Molecular Medicine, "Sapienza" University of Rome, Italy (D.C.)
| |
Collapse
|
16
|
Gauthier MM, Hayoz S, Banek CT. Neuroimmune interplay in kidney health and disease: Role of renal nerves. Auton Neurosci 2023; 250:103133. [PMID: 38061177 PMCID: PMC10748436 DOI: 10.1016/j.autneu.2023.103133] [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: 10/02/2023] [Revised: 11/15/2023] [Accepted: 11/22/2023] [Indexed: 12/18/2023]
Abstract
Renal nerves and their role in physiology and disease have been a topic of increasing interest in the past few decades. Renal inflammation contributes to many cardiorenal disease conditions, including hypertension, chronic kidney disease, and polycystic kidney disease. Much is known about the role of renal sympathetic nerves in physiology - they contribute to the regulation of sodium reabsorption, renin release, and renal vascular resistance. In contrast, far less is known about afferent, or "sensory," renal nerves, which convey signals from the kidney to the brain. While much remains unknown about these nerves in the context of normal physiology, even less is known about their contribution to disease states. Furthermore, it has become apparent that the crosstalk between renal nerves and the immune system may augment or modulate disease. Research from other fields, especially pain research, has provided critical insight into neuroimmune crosstalk. Sympathetic renal nerve activity may increase immune cell recruitment, but far less work has been done investigating the interplay between afferent renal nerves and the immune system. Evidence from other fields suggests that inflammation may augment afferent renal nerve activity. Furthermore, these nerves may exacerbate renal inflammation through the release of afferent-specific neurotransmitters.
Collapse
Affiliation(s)
- Madeline M Gauthier
- Department of Physiology, University of Arizona Health Sciences Center, Tucson, AZ, USA
| | - Sebastien Hayoz
- Department of Physiology, University of Arizona Health Sciences Center, Tucson, AZ, USA
| | - Christopher T Banek
- Department of Physiology, University of Arizona Health Sciences Center, Tucson, AZ, USA.
| |
Collapse
|
17
|
Lale N, Ditting T, Hilgers KF, Linz P, Ott C, Schmieder RE, Schiffer M, Amann K, Veelken R, Rodionova K. Afferent neurons of the kidney with impaired firing pattern in inflammation - role of sodium currents? Pflugers Arch 2023; 475:1329-1342. [PMID: 37672108 PMCID: PMC10567872 DOI: 10.1007/s00424-023-02852-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 08/15/2023] [Accepted: 08/16/2023] [Indexed: 09/07/2023]
Abstract
Peripheral neurons with renal afferents exhibit a predominantly tonic firing pattern of higher frequency that is reduced to low frequencies (phasic firing pattern) in renal inflammation. We wanted to test the hypothesis that the reduction in firing activity during inflammation is due to high-activity tonic neurons switching from higher to low frequencies depending on altered sodium currents. We identified and cultivated afferent sensory neurons with renal projections from the dorsal root ganglia (Th11-L2). Cultivated neurons were incubated with the chemokine CXCL1 (1,5 nmol/ml) for 12 h. We characterized neurons as "tonic," i.e., sustained action potential (AP) firing, or "phasic," i.e., < 5 APs upon stimulation in the current clamp. Their membrane currents were investigated in a voltage clamp. Data analyzed: renal vs. non-renal and tonic vs. phasic neurons. Renal afferent neurons exposed to CXCL1 showed a decrease in tonic firing pattern (CXCL1: 35,6% vs. control: 57%, P < 0.05). Na+ and K+ currents were not different between control renal and non-renal DRG neurons. Phasic neurons exhibited higher Na+ and K+ currents than tonic resulting in shorter APs (3.7 ± 0.3 vs. 6.1 ± 0.6 ms, P < 0.01). In neurons incubated with CXCL1, Na+ and K+ peak current density increased in phasic (Na+: - 969 ± 47 vs. - 758 ± 47 nA/pF, P < 0.01; K+: 707 ± 22 vs. 558 ± 31 nA/pF, P < 0.01), but were unchanged in tonic neurons. Phasic neurons exposed to CXCL1 showed a broader range of Na+ currents ([- 365- - 1429 nA] vs. [- 412- - 4273 nA]; P < 0.05) similar to tonic neurons. After CXCL1 exposure, significant changes in phasic neurons were observed in sodium activation/inactivation as well as a wider distribution of Na+ currents characteristic of tonic neurons. These findings indicate a subgroup of tonic neurons besides mere tonic or phasic neurons exists able to exhibit a phasic activity pattern under pathological conditions.
Collapse
Affiliation(s)
- Nena Lale
- Department of Internal Medicine 4 Nephrology and Hypertension, Friedrich-Alexander University Erlangen, 91054, Erlangen, Germany
| | - Tilmann Ditting
- Department of Internal Medicine 4 Nephrology and Hypertension, Friedrich-Alexander University Erlangen, 91054, Erlangen, Germany
- Department of Internal Medicine 4 - Nephrology and Hypertension, Paracelsus Private Medical School Nuremberg, Nuremberg, Germany
| | - Karl F Hilgers
- Department of Internal Medicine 4 Nephrology and Hypertension, Friedrich-Alexander University Erlangen, 91054, Erlangen, Germany
| | - Peter Linz
- Department of Radiology, Friedrich-Alexander University Erlangen, 91054, Erlangen, Germany
| | - Christian Ott
- Department of Internal Medicine 4 Nephrology and Hypertension, Friedrich-Alexander University Erlangen, 91054, Erlangen, Germany
- Department of Internal Medicine 4 - Nephrology and Hypertension, Paracelsus Private Medical School Nuremberg, Nuremberg, Germany
| | - Roland E Schmieder
- Department of Internal Medicine 4 Nephrology and Hypertension, Friedrich-Alexander University Erlangen, 91054, Erlangen, Germany
| | - Mario Schiffer
- Department of Internal Medicine 4 Nephrology and Hypertension, Friedrich-Alexander University Erlangen, 91054, Erlangen, Germany
| | - Kerstin Amann
- Department of Nephropathology, Friedrich-Alexander University Erlangen, 91054, Erlangen, Germany
| | - Roland Veelken
- Department of Internal Medicine 4 Nephrology and Hypertension, Friedrich-Alexander University Erlangen, 91054, Erlangen, Germany.
- Department of Internal Medicine 4 - Nephrology and Hypertension, Paracelsus Private Medical School Nuremberg, Nuremberg, Germany.
| | - Kristina Rodionova
- Department of Internal Medicine 4 Nephrology and Hypertension, Friedrich-Alexander University Erlangen, 91054, Erlangen, Germany
| |
Collapse
|
18
|
Kharazmi F, Hosseini-Dastgerdi H, Pourshanazari AA, Nematbakhsh M. The denervation or activation of renal sympathetic nerve and renal blood flow. JOURNAL OF RESEARCH IN MEDICAL SCIENCES : THE OFFICIAL JOURNAL OF ISFAHAN UNIVERSITY OF MEDICAL SCIENCES 2023; 28:76. [PMID: 38152073 PMCID: PMC10751519 DOI: 10.4103/jrms.jrms_216_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 07/09/2023] [Accepted: 07/17/2023] [Indexed: 12/29/2023]
Abstract
The denervation or activation of the sympathetic nerve in the kidney can affect renal hemodynamics. The sympathetic nervous system regulates the physiological functions of the kidneys. Stimulation of sympathetic efferent nerves affects various parameters related to renal hemodynamics, including sodium excretion, renin secretion, and renal blood flow (RBF). Hence, renal sympathetic fibers may also play an essential role in regulating systemic vascular resistance and controlling blood pressure. In the absence of renal nerves, the hemodynamics response to stimuli is negligible or absent. The effect of renal sympathetic denervation on RBF is dependent on several factors such as interspecies differences, the basic level of nerve activity in the vessels or local density of adrenergic receptor in the vascular bed. The role of renal denervation has been investigated therapeutically in hypertension and related disorders. Hence, the dynamic impact of renal nerves on RBF enables using RBF dynamic criteria as a marker for renal denervation therapy.
Collapse
Affiliation(s)
- Fatemeh Kharazmi
- Water and Electrolytes Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
- Department of Physiology, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hajaralsadat Hosseini-Dastgerdi
- Water and Electrolytes Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
- Department of Physiology, Isfahan University of Medical Sciences, Isfahan, Iran
| | | | - Mehdi Nematbakhsh
- Water and Electrolytes Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
- Department of Physiology, Isfahan University of Medical Sciences, Isfahan, Iran
| |
Collapse
|
19
|
Lauar MR, Evans LC, Van Helden D, Fink GD, Banek CT, Menani JV, Osborn JW. Renal and hypothalamic inflammation in renovascular hypertension: role of afferent renal nerves. Am J Physiol Regul Integr Comp Physiol 2023; 325:R411-R422. [PMID: 37519252 PMCID: PMC10639016 DOI: 10.1152/ajpregu.00072.2023] [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: 03/24/2023] [Revised: 06/30/2023] [Accepted: 07/25/2023] [Indexed: 08/01/2023]
Abstract
Renal denervation (RDN) is a potential therapy for drug-resistant hypertension. However, whether its effects are mediated by ablation of efferent or afferent renal nerves is not clear. Previous studies have implicated that renal inflammation and the sympathetic nervous system are driven by the activation of afferent and efferent renal nerves. RDN attenuated the renal inflammation and sympathetic activity in some animal models of hypertension. In the 2 kidney,1 clip (2K1C) model of renovascular hypertension, RDN also decreased sympathetic activity; however, mechanisms underlying renal and central inflammation are still unclear. We tested the hypothesis that the mechanisms by which total RDN (TRDN; efferent + afferent) and afferent-specific RDN (ARDN) reduce arterial pressure in 2K1C rats are the same. Male Sprague-Dawley rats were instrumented with telemeters to measure mean arterial pressure (MAP), and after 7 days, a clip was placed on the left renal artery. Rats underwent TRDN, ARDN, or sham surgery of the clipped kidney and MAP was measured for 6 wk. Weekly measurements of water intake (WI), urine output (UO), and urinary copeptin were conducted, and urine was analyzed for cytokines/chemokines. Neurogenic pressor activity (NPA) was assessed at the end of the protocol calculated by the depressor response after intraperitoneal injection of hexamethonium. Rats were euthanized and the hypothalamus and kidneys removed for measurement of cytokine content. MAP, NPA, WI, and urinary copeptin were significantly increased in 2K1C-sham rats, and these responses were abolished by both TRDN and ARDN. 2K1C-sham rats presented with renal and hypothalamic inflammation and these responses were largely mitigated by TRDN and ARDN. We conclude that RDN attenuates 2K1C hypertension primarily by ablation of afferent renal nerves which disrupts bidirectional renal neural-immune pathways.NEW & NOTEWORTHY Hypertension resulting from reduced perfusion of the kidney is dependent on renal sensory nerves, which are linked to inflammation in the kidney and hypothalamus. Afferent renal nerves are required for chronic increases in both water intake and vasopressin release observed following renal artery stenosis. Findings from this study suggest an important role of renal sensory nerves that has previously been underestimated in the pathogenesis of 2K1C hypertension.
Collapse
Affiliation(s)
- Mariana R Lauar
- Department of Surgery, Medical School, University of Minnesota, Minneapolis, Minnesota, United States
- Department of Physiology and Pathology, Dentistry School, São Paulo State University-UNESP, Araraquara, São Paulo, Brazil
| | - Louise C Evans
- Department of Surgery, Medical School, University of Minnesota, Minneapolis, Minnesota, United States
| | - Dusty Van Helden
- Department of Surgery, Medical School, University of Minnesota, Minneapolis, Minnesota, United States
| | - Gregory D Fink
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, United States
| | - Christopher T Banek
- Department of Physiology, University of Arizona Health Sciences, Tucson, Arizona, United States
| | - José V Menani
- Department of Physiology and Pathology, Dentistry School, São Paulo State University-UNESP, Araraquara, São Paulo, Brazil
| | - John W Osborn
- Department of Surgery, Medical School, University of Minnesota, Minneapolis, Minnesota, United States
| |
Collapse
|
20
|
Becker BK, Grady CM, Markl AE, Torres Rodriguez AA, Pollock DM. Elevated renal afferent nerve activity in a rat model of endothelin B receptor deficiency. Am J Physiol Renal Physiol 2023; 325:F235-F247. [PMID: 37348026 PMCID: PMC10396274 DOI: 10.1152/ajprenal.00064.2023] [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: 03/21/2023] [Revised: 06/13/2023] [Accepted: 06/21/2023] [Indexed: 06/24/2023] Open
Abstract
Renal nerves have been an attractive target for interventions aimed at lowering blood pressure; however, the specific roles of renal afferent (sensory) versus efferent sympathetic nerves in mediating hypertension are poorly characterized. A number of studies have suggested that a sympathoexcitatory signal conveyed by renal afferents elicits increases in blood pressure, whereas other studies identified sympathoinhibitory afferent pathways. These sympathoinhibitory pathways have been identified as protective against salt-sensitive increases in blood pressure through endothelin B (ETB) receptor activation. We hypothesized that ETB-deficient (ETB-def) rats, which are devoid of functional ETB receptors except in adrenergic tissues, lack appropriate sympathoinhibition and have lower renal afferent nerve activity following a high-salt diet compared with transgenic controls. We found that isolated renal pelvises from high salt-fed ETB-def animals lack a response to a physiological stimulus, prostaglandin E2, compared with transgenic controls but respond equally to a noxious stimulus, capsaicin. Surprisingly, we observed elevated renal afferent nerve activity in intact ETB-def rats compared with transgenic controls under both normal- and high-salt diets. ETB-def rats have been previously shown to have heightened global sympathetic tone, and we also observed higher total renal sympathetic nerve activity in ETB-def rats compared with transgenic controls under both normal- and high-salt diets. These data indicate that ETB receptors are integral mediators of the sympathoinhibitory renal afferent reflex (renorenal reflex), and, in a genetic rat model of ETB deficiency, the preponderance of sympathoexcitatory renal afferent nerve activity prevails and may contribute to hypertension.NEW & NOTEWORTHY Here, we found that endothelin B receptors are an important contributor to renal afferent nerve responsiveness to a high-salt diet. Rats lacking endothelin B receptors have increased afferent nerve activity that is not responsive to a high-salt diet.
Collapse
Affiliation(s)
- Bryan K Becker
- Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Caroline M Grady
- Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Alexa E Markl
- Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Alfredo A Torres Rodriguez
- Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - David M Pollock
- Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| |
Collapse
|
21
|
Stocker SD, Sullivan JB. Deletion of the Transient Receptor Potential Vanilloid 1 Channel Attenuates Sympathoexcitation and Hypertension and Improves Glomerular Filtration Rate in 2-Kidney-1-Clip Rats. Hypertension 2023; 80:1671-1682. [PMID: 37334698 PMCID: PMC10527253 DOI: 10.1161/hypertensionaha.123.21153] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 06/06/2023] [Indexed: 06/20/2023]
Abstract
BACKGROUND Renal denervation lowers arterial blood pressure in both clinical populations and multiple experimental models of hypertension. This therapeutic effect is partly attributed to the removal of overactive renal sensory nerves. The TRPV1 (transient receptor potential vanilloid 1) channel is highly expressed in renal sensory nerves and detects changes in noxious and mechanosensitive stimuli, pH, and chemokines. However, the extent to which TRPV1 channels contribute to 2-kidney-1-clip (2K1C) renovascular hypertension has not been tested. METHODS We generated a novel Trpv1-/- (TRPV1 knockout) rat using CRISPR/Cas9 and 26-bp deletion in exon 3 and induced 2K1C hypertension. RESULTS The majority (85%) of rat renal sensory neurons retrogradely labeled from the kidney were TRPV1-positive. Trpv1-/- rats lacked TRPV1 immunofluorescence in the dorsal root ganglia, had a delayed tail-flick response to hot but not cold water, and lacked an afferent renal nerve activity response to intrarenal infusion of the TRPV1 agonist capsaicin. Interestingly, 2K1C hypertension was significantly attenuated in male Trpv1-/- versus wild-type rats. 2K1C hypertension significantly increased the depressor response to ganglionic blockade, total renal nerve activity (efferent and afferent), and afferent renal nerve activity in wild-type rats, but these responses were attenuated in male Trpv1-/- rats. 2K1C hypertension was attenuated in female rats with no differences between female strains. Finally, glomerular filtration rate was reduced by 2K1C in wild-type rats but improved in Trpv1-/- rats. CONCLUSIONS These findings suggest that renovascular hypertension requires activation of the TRPV1 channel to elevate renal afferent and sympathetic nerve activity, reduce glomerular filtration rate, and increase arterial blood pressure.
Collapse
Affiliation(s)
- Sean D Stocker
- Department of Neurobiology, University of Pittsburgh School of Medicine, PA
| | - Jacob B Sullivan
- Department of Neurobiology, University of Pittsburgh School of Medicine, PA
| |
Collapse
|
22
|
Parvin I, Gauthier MM, Dennis MR, Encinas NM, Nangia EL, Schwartz KL, Banek CT. Sequential afferent and sympathetic renal denervation impact on cardiovascular and renal homeostasis in the male Sprague-Dawley rat. Life Sci 2023; 325:121768. [PMID: 37169146 PMCID: PMC10225348 DOI: 10.1016/j.lfs.2023.121768] [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: 03/28/2023] [Revised: 05/05/2023] [Accepted: 05/05/2023] [Indexed: 05/13/2023]
Abstract
Renal denervation (RDNx) is emerging as a promising treatment for cardiovascular disease, yet the underlying mechanisms and contributions of afferent (sensory) and efferent (sympathetic) renal nerves in healthy conditions remains limited. We hypothesize that sympathetic renal nerves contribute to long-term MAP and renal function, whereas afferent renal nerves do not contribute to the maintenance of cardiovascular and renal function. To test this hypothesis, we performed two experiments. In experiment one, we performed total renal denervation (T-RDNx), ablating afferent and sympathetic renal nerves, in normotensive adult SD rats to determine effects on MAP and renal function. Experiment 2 employed a sequential surgical ablation using: (1) afferent targeted renal denervation (A-RDNx), then (2) sympathetic (T-RDNx) denervation to determine the individual contributions to cardiovascular and renal homeostasis. In experiment 1, MAP decreased following T-RDNx and GFR increased. In experiment 2, A-RDNx led to an increase in MAP but did not change renal function. In contrast, T-RDNx decreased MAP and improved renal filtration. Together, these data partially support our hypothesis that renal sympathetic nerves contribute to the chronic regulation of arterial pressure and renal function. Contrary to the hypothesis, A-RDNx produced an increase in MAP without a detected change in renal function. We concluded that renal sympathetic nerves influence MAP and renal function regulation through a well-defined tonic contribution to renal vascular resistance and sodium reabsorption, whereas afferent renal nerves likely contribute to the maintenance of MAP through a tonic sympatho-inhibitory, negative feedback regulation in the normotensive, healthy rat.
Collapse
Affiliation(s)
- Irin Parvin
- Department of Physiology, University of Arizona College of Medicine, Tucson, AZ, USA
| | - Madeline M Gauthier
- Department of Physiology, University of Arizona College of Medicine, Tucson, AZ, USA
| | - Melissa R Dennis
- Department of Physiology, University of Arizona College of Medicine, Tucson, AZ, USA
| | - Noah M Encinas
- Department of Physiology, University of Arizona College of Medicine, Tucson, AZ, USA
| | - Ellen L Nangia
- Department of Physiology, University of Arizona College of Medicine, Tucson, AZ, USA
| | - Kyle L Schwartz
- Department of Physiology, University of Arizona College of Medicine, Tucson, AZ, USA
| | - Christopher T Banek
- Department of Physiology, University of Arizona College of Medicine, Tucson, AZ, USA.
| |
Collapse
|
23
|
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] [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.
Collapse
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
| |
Collapse
|
24
|
Liu H, Li Y, Zhou H, Chen W, Xu Y, Du H, Zhang B, Xia T, Li D, Ou Z, Tang R, Chen Q, Zhao B, Yin Y. Renal nerve stimulation identifies renal innervation and optimizes the strategy for renal denervation in canine. J Transl Med 2023; 21:100. [PMID: 36759871 PMCID: PMC9912587 DOI: 10.1186/s12967-023-03919-9] [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: 06/10/2022] [Accepted: 01/25/2023] [Indexed: 02/11/2023] Open
Abstract
BACKGROUND Renal denervation (RDN) was still performed without any intra-procedural method for nerve mapping. Whether renal nerve stimulation (RNS) is an efficient way to identify renal autonomic innervation and optimize the strategy for RDN remain to be worthy for further exploration. METHODS The characteristics of renal autonomic innervation at the sites with different blood pressure (BP) responses to RNS were explored. Then, dogs anatomically eligible for RDN were randomly assigned into elevated BP response ablation group, reduced BP response ablation group, and RNS-control group. The postoperative outcomes were measured at baseline and after 4 weeks follow-up. RESULTS The proportion of afferent sensory nerve was higher at elevated BP response sites (ERS) than reduced BP response sites (RRS) and non-response sites (NRS) (P = 0.012 and P = 0.004). Conversely, the proportion of parasympathetic nerve at RRS was the highest (RRS vs. ERS, P = 0.017; RRS vs. NRS, P = 0.023). More importantly, there was a significant correlation between systolic blood pressure changes and the area ratios of afferent sensory and parasympathetic nerve (R = 0.859; P < 0.001). In addition, ablation at BP-elevation sites can result in a significant decrease in BP and plasma norepinephrine (NE) after 4 weeks (P = 0.002; P = 0.008), while ablation at BP-reduction sites can lead to significant increases in BP and plasma NE (P = 0.016; P = 0.033). CONCLUSIONS RNS is an effective method to identify renal autonomic innervation. It could not only help to identify optimal target sites, but also avoid ablation of sympathetic-inhibitory areas during RDN.
Collapse
Affiliation(s)
- Hang Liu
- grid.412461.40000 0004 9334 6536Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China ,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China
| | - Yidan Li
- grid.412461.40000 0004 9334 6536Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China ,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China
| | - Hao Zhou
- grid.412461.40000 0004 9334 6536Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China ,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China
| | - Weijie Chen
- grid.412461.40000 0004 9334 6536Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China ,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China
| | - Yanping Xu
- grid.412461.40000 0004 9334 6536Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China ,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China
| | - Huaan Du
- grid.412461.40000 0004 9334 6536Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China ,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China
| | - Bo Zhang
- grid.412461.40000 0004 9334 6536Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China ,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China
| | - Tianli Xia
- grid.412461.40000 0004 9334 6536Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China ,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China
| | - Dan Li
- grid.412461.40000 0004 9334 6536Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China ,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China
| | - Zhenhong Ou
- grid.412461.40000 0004 9334 6536Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China ,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China
| | - Ruotian Tang
- grid.412461.40000 0004 9334 6536Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China ,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China
| | - Qingsong Chen
- grid.412461.40000 0004 9334 6536Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China ,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China
| | - Binyi Zhao
- grid.412461.40000 0004 9334 6536Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China ,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China
| | - Yuehui Yin
- Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China. .,Chongqing Cardiac Arrhythmias Therapeutic Service Center, Chongqing, China. .,Chongqing Key Laboratory of Arrhythmia, Chongqing, China.
| |
Collapse
|
25
|
Tyshynsky R, Sensarma S, Riedl M, Bukowy J, Schramm LP, Vulchanova L, Osborn JW. Periglomerular afferent innervation of the mouse renal cortex. Front Neurosci 2023; 17:974197. [PMID: 36777644 PMCID: PMC9909228 DOI: 10.3389/fnins.2023.974197] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 01/09/2023] [Indexed: 01/27/2023] Open
Abstract
Recent studies using a novel method for targeted ablation of afferent renal nerves have demonstrated their importance in the development and maintenance of some animal models of hypertension. However, relatively little is known about the anatomy of renal afferent nerves distal to the renal pelvis. Here, we investigated the anatomical relationship between renal glomeruli and afferent axons identified based on transient receptor potential vanilloid 1 channel (TRPV1) lineage or calcitonin gene related peptide (CGRP) immunolabeling. Analysis of over 6,000 (10,000 was accurate prior to the removal of the TH data during the review process) glomeruli from wildtype C57BL/6J mice and transgenic mice expressing tdTomato in TRPV1 lineage cells indicated that approximately half of all glomeruli sampled were closely apposed to tdTomato+ or CGRP+ afferent axons. Glomeruli were categorized as superficial, midcortical, or juxtamedullary based on their depth within the cortex. Juxtamedullary glomeruli were more likely to be closely apposed by afferent axon subtypes than more superficial glomeruli. High-resolution imaging of thick, cleared renal slices and subsequent distance transformations revealed that CGRP+ axons closely apposed to glomeruli were often found within 2 microns of nephrin+ labeling of glomerular podocytes. Furthermore, imaging of thick slices suggested that CGRP+ axon bundles can closely appose multiple glomeruli that share the same interlobular artery. Based on their expression of CGRP or tdTomato, prevalence near glomeruli, proximity to glomerular structures, and close apposition to multiple glomeruli within a module, we hypothesize that periglomerular afferent axons may function as mechanoreceptors monitoring glomerular pressure. These anatomical findings highlight the importance of further studies investigating the physiological role of periglomerular afferent axons in neural control of renal function in health and disease.
Collapse
Affiliation(s)
- Roman Tyshynsky
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN, United States
| | - Sulagna Sensarma
- Department of Surgery, University of Minnesota, Minneapolis, MN, United States
| | - Maureen Riedl
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, United States
| | - John Bukowy
- Department of Electrical Engineering and Computer Science, Milwaukee School of Engineering, Milwaukee, WI, United States
| | - Lawrence P. Schramm
- Department of Biomedical Engineering, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Lucy Vulchanova
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN, United States,Department of Neuroscience, University of Minnesota, Minneapolis, MN, United States
| | - John W. Osborn
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN, United States,Department of Surgery, University of Minnesota, Minneapolis, MN, United States,*Correspondence: John W. Osborn,
| |
Collapse
|
26
|
Zucker IH, Xia Z, Wang HJ. Potential Neuromodulation of the Cardio-Renal Syndrome. J Clin Med 2023; 12:803. [PMID: 36769450 PMCID: PMC9917464 DOI: 10.3390/jcm12030803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/20/2023] Open
Abstract
The cardio-renal syndrome (CRS) type 2 is defined as a progressive loss of renal function following a primary insult to the myocardium that may be either acute or chronic but is accompanied by a decline in myocardial pump performance. The treatment of patients with CRS is difficult, and the disease often progresses to end-stage renal disease that is refractory to conventional therapy. While a good deal of information is known concerning renal injury in the CRS, less is understood about how reflex control of renal sympathetic nerve activity affects this syndrome. In this review, we provide insight into the role of the renal nerves, both from the afferent or sensory side and from the efferent side, in mediating renal dysfunction in CRS. We discuss how interventions such as renal denervation and abrogation of systemic reflexes may be used to alleviate renal dysfunction in the setting of chronic heart failure. We specifically focus on a novel cardiac sensory reflex that is sensitized in heart failure and activates the sympathetic nervous system, especially outflow to the kidney. This so-called Cardiac Sympathetic Afferent Reflex (CSAR) can be ablated using the potent neurotoxin resinferitoxin due to the high expression of Transient Receptor Potential Vanilloid 1 (TRPV1) receptors. Following ablation of the CSAR, several markers of renal dysfunction are reversed in the post-myocardial infarction heart failure state. This review puts forth the novel idea of neuromodulation at the cardiac level in the treatment of CRS Type 2.
Collapse
Affiliation(s)
- Irving H. Zucker
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Zhiqiu Xia
- Department of Anesthesiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Han-Jun Wang
- Department of Anesthesiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| |
Collapse
|
27
|
Contribution of afferent renal nerve signals to acute and chronic blood pressure regulation in stroke-prone spontaneously hypertensive rats. Hypertens Res 2023; 46:268-279. [PMID: 36369375 DOI: 10.1038/s41440-022-01091-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 10/27/2022] [Accepted: 10/28/2022] [Indexed: 11/13/2022]
Abstract
The activation of sympathetic nervous system plays a critical role in the development of hypertension. The input from afferent renal nerves may affect central sympathetic outflow; however, its contribution to the development of hypertension remains unclear. We investigated the role of afferent renal nerves in acute and chronic blood pressure regulation using normotensive Wistar-Kyoto rats (WKY) and stroke-prone spontaneously hypertensive rats (SHRSP). Acute chemical stimulation of afferent renal nerves elicited larger increases in blood pressure and renal sympathetic nerve activity in young 9-week-old SHRSP compared to WKY. Selective afferent renal denervation (ARDN) and conventional total renal denervation (TRDN) ablating both afferent and efferent nerves in young SHRSP revealed that only TRDN, but not ARDN, chronically attenuated blood pressure elevation. ARDN did not affect plasma renin activity or plasma angiotensin II levels, whereas TRDN decreased both. Neither TRDN nor ARDN affected central sympathetic outflow and systemic sympathetic activity determined by neuronal activity in the parvocellular region of hypothalamic paraventricular nucleus and rostral ventrolateral medulla and by plasma and urinary norepinephrine levels, respectively. Renal injury was not apparent in young SHRSP compared with WKY, suggesting that renal afferent input might not be activated in young SHRSP. In conclusion, the chronic input from afferent renal nerves does not contribute to the development of hypertension in SHRSP despite the increased blood pressure response to the acute stimulation of afferent renal nerves. Efferent renal nerves may be involved in the development of hypertension via activation of the renin-angiotensin system in SHRSP.
Collapse
|
28
|
DeLalio LJ, Stocker SD. Sympathoexcitatory responses to renal chemosensitive stimuli are exaggerated at nighttime in rats. Am J Physiol Heart Circ Physiol 2022; 323:H437-H448. [PMID: 35867707 PMCID: PMC9394783 DOI: 10.1152/ajpheart.00665.2021] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 07/14/2022] [Accepted: 07/14/2022] [Indexed: 11/22/2022]
Abstract
The circadian cycle impacts sympathetic nerve activity (SNA), cardiovascular hemodynamics, and renal function. Activation of renal sensory nerves by chemosensory and mechanosensory stimuli reflexively changes efferent SNA and arterial blood pressure (ABP) to maintain homeostasis. However, it is unclear to what extent circadian cycle influences reflex SNA and ABP responses to renal sensory stimuli. Renal, splanchnic, and lumbar SNA and ABP responses to intrarenal arterial infusion of bradykinin or capsaicin and elevated renal pelvic pressure were measured in male and female Sprague-Dawley rats during nighttime (wakeful/active phase) and daytime (inactive phase). Intrarenal arterial bradykinin infusion significantly increased efferent renal SNA, splanchnic SNA, and ABP but not lumbar SNA. Responses were greater during nighttime versus daytime. Similarly, intrarenal arterial capsaicin infusion significantly increased renal SNA and splanchnic SNA, and responses were again greater during nighttime. Elevated renal pelvic pressure increased renal SNA and splanchnic SNA; however, responses did not differ between daytime and nighttime. Finally, afferent renal nerve activity responses to bradykinin were not different between daytime and nighttime. Thus, renal chemokines elicit greater sympathoexcitatory responses at nighttime that cannot be attributed to differences in afferent renal nerve activity. Collectively, these data suggest that the circadian cycle alters the excitability of central autonomic networks to alter baseline SNA and ABP as well as the magnitude of visceral reflexes.NEW & NOTEWORTHY The current study discovers that the circadian cycle influences sympathetic and hemodynamic responses to activation of renal chemosensitive sensory fibers. Sympathetic responses to intrarenal bradykinin or capsaicin infusion were exaggerated during nighttime (active period), but mechanosensitive responses to elevated renal pelvic pressure were not. Importantly, renal afferent nerve responses were not different between nighttime and daytime. These data suggest that the circadian cycle modulates sympathetic responses to visceral afferent activation.
Collapse
Affiliation(s)
- Leon J DeLalio
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Sean D Stocker
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| |
Collapse
|
29
|
Patel KP, Katsurada K, Zheng H. Cardiorenal Syndrome: The Role of Neural Connections Between the Heart and the Kidneys. Circ Res 2022; 130:1601-1617. [PMID: 35549375 PMCID: PMC9179008 DOI: 10.1161/circresaha.122.319989] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The maintenance of cardiovascular homeostasis is highly dependent on tightly controlled interactions between the heart and the kidneys. Therefore, it is not surprising that a dysfunction in one organ affects the other. This interlinking relationship is aptly demonstrated in the cardiorenal syndrome. The characteristics of the cardiorenal syndrome state include alterations in neurohumoral drive, autonomic reflexes, and fluid balance. The evidence suggests that several factors contribute to these alterations. These may include peripheral and central nervous system abnormalities. However, accumulating evidence from animals with experimental models of congestive heart failure and renal dysfunction as well as humans with the cardiorenal syndrome suggests that alterations in neural pathways, from and to the kidneys and the heart, including the central nervous system are involved in regulating sympathetic outflow and may be critically important in the alterations in neurohumoral drive, autonomic reflexes, and fluid balance commonly observed in the cardiorenal syndrome. This review focuses on studies implicating neural pathways, particularly the afferent and efferent signals from the heart and the kidneys integrating at the level of the paraventricular nucleus in the hypothalamus to alter neurohumoral drive, autonomic pathways, and fluid balance. Further, it explores the potential mechanisms of action for the known beneficial use of various medications or potential novel therapeutic manipulations for the treatment of the cardiorenal syndrome. A comprehensive understanding of these mechanisms will enhance our ability to treat cardiorenal conditions and their cardiovascular complications more efficaciously and thoroughly.
Collapse
Affiliation(s)
- Kaushik P Patel
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (K.P.P.)
| | - Kenichi Katsurada
- Division of Cardiovascular Medicine, Department of Internal Medicine (K.K.), Jichi Medical University School of Medicine, Shimotsuke, Tochigi, Japan.,Division of Clinical Pharmacology, Department of Pharmacology (K.K.), Jichi Medical University School of Medicine, Shimotsuke, Tochigi, Japan
| | - Hong Zheng
- Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion (H.Z.)
| |
Collapse
|
30
|
Hengel FE, Benitah JP, Wenzel UO. Mosaic theory revised: inflammation and salt play central roles in arterial hypertension. Cell Mol Immunol 2022; 19:561-576. [PMID: 35354938 PMCID: PMC9061754 DOI: 10.1038/s41423-022-00851-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 02/21/2022] [Indexed: 02/06/2023] Open
Abstract
The mosaic theory of hypertension was advocated by Irvine Page ~80 years ago and suggested that hypertension resulted from the close interactions of different causes. Increasing evidence indicates that hypertension and hypertensive end-organ damage are not only mediated by the proposed mechanisms that result in hemodynamic injury. Inflammation plays an important role in the pathophysiology and contributes to the deleterious consequences of arterial hypertension. Sodium intake is indispensable for normal body function but can be detrimental when it exceeds dietary requirements. Recent data show that sodium levels also modulate the function of monocytes/macrophages, dendritic cells, and different T-cell subsets. Some of these effects are mediated by changes in the microbiome and metabolome due to high-salt intake. The purpose of this review is to propose a revised and extended version of the mosaic theory by summarizing and integrating recent advances in salt, immunity, and hypertension research. Salt and inflammation are placed in the middle of the mosaic because both factors influence each of the remaining pieces.
Collapse
|
31
|
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] [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
| |
Collapse
|
32
|
Gauthier MM, Dennis MR, Morales MN, Brooks HL, Banek CT. Contribution of Afferent Renal Nerves to Cystogenesis and Arterial Pressure Regulation in a Preclinical Model of Autosomal Recessive Polycystic Kidney Disease. Am J Physiol Renal Physiol 2022; 322:F680-F691. [PMID: 35466689 PMCID: PMC9159540 DOI: 10.1152/ajprenal.00009.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Polycystic kidney disease (PKD) is the most common inheritable cause of kidney failure, and the underlying mechanisms remain incompletely uncovered. Renal nerves contribute to hypertension and chronic kidney disease - frequent complications of PKD. There is limited evidence that renal nerves may contribute to cardiorenal dysfunction in PKD, and no investigations of the role of sympathetic versus afferent nerves in PKD. Afferent renal nerve activity (ARNA) is elevated in models of renal disease and fibrosis. However, it remains unknown if this is true in PKD. We tested the hypothesis that ARNA is elevated in a preclinical model of autosomal recessive PKD (ARPKD), and that targeted renal nerve ablation would attenuate cystogenesis and cardiorenal dysfunction. We tested this by performing a total (T-RDNx) or afferent (A-RDNx) denervation in 4-week-old male and female PCK rats, then quantifying renal and cardiovascular responses 6 weeks following treatment. Cystogenesis was attenuated with A-RDNx and T-RDNx vs. sham controls, highlighting a crucial role for renal afferent nerves in cystogenesis. In contrast, blood pressure was improved with T-RDNx but not A-RDNx. Importantly, treatments produced similar results in both males and females. Direct renal afferent nerve recordings revealed that ARNA was 2-fold greater in PCK rats vs. non-cystic controls and was directly correlated to cystic severity. To our knowledge, we are the first to demonstrate that PCK rats have greater ARNA than non-cystic, age-matched controls. The findings of these studies support a novel and crucial role for renal afferent innervation in cystogenesis in the PCK rat.
Collapse
Affiliation(s)
- Madeline M Gauthier
- Department of Physiology, University of Arizona Health Sciences Center, Tucson, AZ, United States
| | - Melissa R Dennis
- Department of Physiology, University of Arizona Health Sciences Center, Tucson, AZ, United States
| | - Mark N Morales
- Department of Physiology, University of Arizona Health Sciences Center, Tucson, AZ, United States
| | - Heddwen L Brooks
- Department of Physiology, University of Arizona Health Sciences Center, Tucson, AZ, United States
| | - Christopher T Banek
- Department of Physiology, University of Arizona Health Sciences Center, Tucson, AZ, United States.,Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis, MN, United States
| |
Collapse
|
33
|
Carnevale D. Neuroimmune axis of cardiovascular control: mechanisms and therapeutic implications. Nat Rev Cardiol 2022; 19:379-394. [PMID: 35301456 DOI: 10.1038/s41569-022-00678-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/07/2022] [Indexed: 12/21/2022]
Abstract
Cardiovascular diseases (CVDs) make a substantial contribution to the global burden of disease. Prevention strategies have succeeded in reducing the effect of acute CVD events and deaths, but the long-term consequences of cardiovascular risk factors still represent the major cause of disability and chronic illness, suggesting that some pathophysiological mechanisms might not be adequately targeted by current therapies. Many of the underlying causes of CVD have now been recognized to have immune and inflammatory components. However, inflammation and immune activation were mostly regarded as a consequence of target-organ damage. Only more recent findings have indicated that immune dysregulation can be pathogenic for CVD, identifying a need for novel immunomodulatory therapeutic strategies. The nervous system, through an array of afferent and efferent arms of the autonomic nervous system, profoundly affects cardiovascular function. Interestingly, the autonomic nervous system also innervates immune organs, and neuroimmune interactions that are biologically relevant to CVD have been discovered, providing the foundation to target neural reflexes as an immunomodulatory therapeutic strategy. This Review summarizes how the neural regulation of immunity and inflammation participates in the onset and progression of CVD and explores promising opportunities for future therapeutic strategies.
Collapse
Affiliation(s)
- Daniela Carnevale
- Department of Molecular Medicine, Sapienza University, Rome, Italy. .,Research Unit of Neuro and Cardiovascular Pathophysiology, IRCCS Neuromed, Pozzilli, Italy.
| |
Collapse
|
34
|
Minic Z, O’Leary DS, Reynolds CA. Spinal Reflex Control of Arterial Blood Pressure: The Role of TRP Channels and Their Endogenous Eicosanoid Modulators. Front Physiol 2022; 13:838175. [PMID: 35283783 PMCID: PMC8904930 DOI: 10.3389/fphys.2022.838175] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 01/26/2022] [Indexed: 01/14/2023] Open
Abstract
The spinal cord is an important integrative center for blood pressure control. Spinal sensory fibers send projections to sympathetic preganglionic neurons of the thoracic spinal cord and drive sympathetically-mediated increases in blood pressure. While these reflexes responses occur in able-bodied individuals, they are exaggerated following interruption of descending control - such as occurs following spinal cord injury. Similar reflex control of blood pressure may exist in disease states, other than spinal cord injury, where there is altered input to sympathetic preganglionic neurons. This review primarily focuses on mechanisms wherein visceral afferent information traveling via spinal nerves influences sympathetic nerve activity and blood pressure. There is an abundance of evidence for the widespread presence of this spinal reflex arch originating from virtually every visceral organ and thus having a substantial role in blood pressure control. Additionally, this review highlights specific endogenous eicosanoid species, which modulate the activity of afferent fibers involved in this reflex, through their interactions with transient receptor potential (TRP) cation channels.
Collapse
Affiliation(s)
- Zeljka Minic
- Department of Emergency Medicine Wayne State University School of Medicine, Detroit, MI, United States
- Department of Biotechnology, University of Rijeka, Rijeka, Croatia
| | - Donal S. O’Leary
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, United States
| | - Christian A. Reynolds
- Department of Emergency Medicine Wayne State University School of Medicine, Detroit, MI, United States
- Department of Biotechnology, University of Rijeka, Rijeka, Croatia
| |
Collapse
|
35
|
Renal denervation: basic and clinical evidence. Hypertens Res 2022; 45:198-209. [PMID: 34921299 DOI: 10.1038/s41440-021-00827-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 11/29/2021] [Accepted: 11/30/2021] [Indexed: 01/20/2023]
Abstract
Renal nerves have critical roles in regulating blood pressure and fluid volume, and their dysfunction is closely related with cardiovascular diseases. Renal nerves are composed of sympathetic efferent and sensory afferent nerves. Activation of the efferent renal sympathetic nerves induces renin secretion, sodium absorption, and increased renal vascular resistance, which lead to increased blood pressure and fluid retention. Afferent renal sensory nerves, which are densely innervated in the renal pelvic wall, project to the hypothalamic paraventricular nucleus in the brain to modulate sympathetic outflow to the periphery, including the heart, kidneys, and arterioles. The effects of renal denervation on the cardiovascular system are mediated by both efferent denervation and afferent denervation. The first half of this review focuses on basic research using animal models of hypertension and heart failure, and addresses the therapeutic effects of renal denervation for hypertension and heart failure, including underlying mechanisms. The second half of this review focuses on clinical research related to catheter-based renal denervation in patients with hypertension. Randomized sham-controlled trials using second-generation devices, endovascular radiofrequency-based devices and ultrasound-based devices are reviewed and their results are assessed. This review summarizes the basic and clinical evidence of renal denervation to date, and discusses future prospects and potential developments in renal denervation therapy for cardiovascular diseases.
Collapse
|
36
|
Perrotta M, Carnevale D. Brain Areas Involved in Modulating the Immune Response Participating in Hypertension and Its Target Organ Damage. Antioxid Redox Signal 2021; 35:1515-1530. [PMID: 34269604 DOI: 10.1089/ars.2021.0142] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Significance: Hypertension is a multifactorial disease ensuing from the continuous challenge imposed by several risk factors on the cardiovascular system. Classically known pathophysiological alterations associated with hypertension comprise neurogenic mechanisms dysregulating the autonomic nervous system (ANS), vascular dysfunction, and excessive activation of the renin angiotensin system. During the past few years, a considerable number of studies indicated that immune activation and inflammation also have an important role in the onset and maintenance of hypertension. Critical Issues: On these premises, it has been necessary to reconsider the pathophysiological mechanisms underlying hypertension development, taking into account the potential interactions established between classically known determinants of high blood pressure and the immune system. Recent Advances: Interestingly, central nervous system areas controlling cardiovascular functions are enriched with Angiotensin II receptors. Observations showing that these brain areas are crucial for mediating peripheral ANS and immune responses were suggestive of a critical role of neuroimmune interactions in hypertension. In fact, the ANS, characterized by an intricate network of afferent and efferent fibers, represents an intermediate between the brain and peripheral responses that are essential for blood pressure regulation. Future Directions: In this review, we will summarize studies showing how specific brain areas can modulate immune responses that are involved in hypertension. Antioxid. Redox Signal. 35, 1515-1530.
Collapse
Affiliation(s)
- Marialuisa Perrotta
- Department of Molecular Medicine, "Sapienza" University of Rome, Rome, Italy
| | - Daniela Carnevale
- Department of Molecular Medicine, "Sapienza" University of Rome, Rome, Italy.,Research Unit of Neuro and Cardiovascular Pathophysiology, IRCCS Neuromed, Pozzilli, Italy
| |
Collapse
|
37
|
Katsurada K, Kario K. Neural afferents as potential targets to ameliorate FGF21-mediated sympathoexcitation. Hypertens Res 2021; 45:372-375. [PMID: 34880422 DOI: 10.1038/s41440-021-00811-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 11/02/2021] [Accepted: 11/02/2021] [Indexed: 11/09/2022]
Affiliation(s)
- Kenichi Katsurada
- Division of Cardiovascular Medicine, Department of Internal Medicine, Jichi Medical University School of Medicine, Shimotsuke, Tochigi, Japan.,Division of Clinical Pharmacology, Department of Pharmacology, Jichi Medical University School of Medicine, Shimotsuke, Tochigi, Japan
| | - Kazuomi Kario
- Division of Cardiovascular Medicine, Department of Internal Medicine, Jichi Medical University School of Medicine, Shimotsuke, Tochigi, Japan.
| |
Collapse
|
38
|
Mariano VS, Boer PA, Gontijo JAR. Fetal Undernutrition Programming, Sympathetic Nerve Activity, and Arterial Hypertension Development. Front Physiol 2021; 12:704819. [PMID: 34867434 PMCID: PMC8635863 DOI: 10.3389/fphys.2021.704819] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 10/14/2021] [Indexed: 12/11/2022] Open
Abstract
A wealth of evidence showed that low birth weight is associated with environmental disruption during gestation, triggering embryotic or fetal adaptations and increasing the susceptibility of progeny to non-communicable diseases, including metabolic and cardiovascular diseases, obesity, and arterial hypertension. In addition, dietary disturbance during pregnancy in animal models has highlighted mechanisms that involve the genesis of arterial hypertension, particularly severe maternal low-protein intake (LP). Functional studies demonstrated that maternal low-protein intake leads to the renal decrease of sodium excretion and the dysfunction of the renin-angiotensin-aldosterone system signaling of LP offspring. The antinatriuretic effect is accentuated by a reduced number of nephron units and glomerulosclerosis, which are critical in establishing arterial hypertension phenotype. Also, in this way, studies have shown that the overactivity of the central and peripheral sympathetic nervous system occurs due to reduced sensory (afferent) renal nerve activity. As a result of this reciprocal and abnormal renorenal reflex, there is an enhanced tubule sodium proximal sodium reabsorption, which, at least in part, contributes directly to arterial hypertension development in some of the programmed models. A recent study has observed that significant changes in adrenal medulla secretion could be involved in the pathophysiological process of increasing blood pressure. Thus, this review aims to compile studies that link the central and peripheral sympathetic system activity mechanisms on water and salt handle and blood pressure control in the maternal protein-restricted offspring. Besides, these pathophysiological mechanisms mainly may involve the modulation of neurokinins and catecholamines pathways.
Collapse
Affiliation(s)
- Vinícius Schiavinatto Mariano
- Fetal Programming and Hydroelectrolyte Metabolism Laboratory, Nucleus of Medicine and Experimental Surgery, Department of Internal Medicine, Faculty of Medical Sciences, State University of Campinas, São Paulo, Brazil
| | - Patrícia Aline Boer
- Fetal Programming and Hydroelectrolyte Metabolism Laboratory, Nucleus of Medicine and Experimental Surgery, Department of Internal Medicine, Faculty of Medical Sciences, State University of Campinas, São Paulo, Brazil
| | - José Antônio Rocha Gontijo
- Fetal Programming and Hydroelectrolyte Metabolism Laboratory, Nucleus of Medicine and Experimental Surgery, Department of Internal Medicine, Faculty of Medical Sciences, State University of Campinas, São Paulo, Brazil
| |
Collapse
|
39
|
Katsurada K, Nandi SS, Sharma NM, Patel KP. Enhanced Expression and Function of Renal SGLT2 (Sodium-Glucose Cotransporter 2) in Heart Failure: Role of Renal Nerves. Circ Heart Fail 2021; 14:e008365. [PMID: 34789005 PMCID: PMC8692398 DOI: 10.1161/circheartfailure.121.008365] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Recent clinical studies demonstrate that SGLT2 (sodium-glucose cotransporter 2) inhibitors ameliorate heart failure (HF). The present study was conducted to assess the expression and function of renal SGLT2 and the influence of enhanced renal sympathetic tone in HF. METHODS Four weeks after coronary artery ligation surgery to induce HF, surgical bilateral renal denervation (RDN) was performed in rats. Four groups of rats (Sham-operated control [Sham], Sham+RDN, HF and HF+RDN; n=6/group) were used. Immunohistochemistry and Western blot analysis were performed to evaluate the renal SGLT2 expression. One week after RDN (5 weeks after induction of HF), intravenous injection of SGLT2 inhibitor dapagliflozin were performed to assess renal excretory responses. In vitro, human embryonic kidney cells were used to investigate the fractionation of SGLT2 after norepinephrine treatment. RESULTS In rats with HF, (1) SGLT2 expression in the proximal tubule of the kidney was increased; (2) the response of increases in urine flow, sodium excretion, and glucose excretion to dapagliflozin were greater; and (3) RDN attenuated renal SGLT2 expression and normalized renal functional responses to dapagliflozin. In vitro, norepinephrine promoted translocation of SGLT2 to the cell membrane. CONCLUSIONS These results indicate that the enhanced tonic renal sympathetic nerve activation in HF increases the expression and functional activity of renal SGLT2. Potentiated trafficking of SGLT2 to cell surface in renal proximal tubules mediated by norepinephrine may contribute to this functional activation of SGLT2 in HF. These findings provide critical insight into the underlying mechanisms for the beneficial effects of SGLT2 inhibitors on HF reported in the clinical studies.
Collapse
Affiliation(s)
- Kenichi Katsurada
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha
| | - Shyam S Nandi
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha
| | - Neeru M Sharma
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha
| | - Kaushik P Patel
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha
| |
Collapse
|
40
|
Renal denervation based on experimental rationale. Hypertens Res 2021; 44:1385-1394. [PMID: 34518650 PMCID: PMC9577563 DOI: 10.1038/s41440-021-00746-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 08/03/2021] [Accepted: 08/16/2021] [Indexed: 02/07/2023]
Abstract
Excessive activation of the sympathetic nervous system is one of the pathophysiological hallmarks of hypertension and heart failure. Within the central nervous system, the paraventricular nucleus (PVN) of the hypothalamus and the rostral ventrolateral medulla in the brain stem play critical roles in the regulation of sympathetic outflow to peripheral organs. Information from the peripheral circulation, including serum concentrations of sodium and angiotensin II, is conveyed to the PVN via adjacent structures with a weak blood-brain barrier. In addition, signals from baroreceptors, chemoreceptors and cardiopulmonary receptors as well as afferent input via the renal nerves are all integrated at the level of the PVN. The brain renin-angiotensin system and the balance between nitric oxide and reactive oxygen species in these brain areas also determine the final sympathetic outflow. Additionally, brain inflammatory responses have been shown to modulate these processes. Renal denervation interrupts both the afferent inputs from the kidney to the PVN and the efferent outputs from the PVN to the kidney, resulting in the suppression of sympathetic outflow and eliciting beneficial effects on both hypertension and heart failure.
Collapse
|
41
|
DeLalio LJ, Stocker SD. Impact of anesthesia and sex on sympathetic efferent and hemodynamic responses to renal chemo- and mechanosensitive stimuli. J Neurophysiol 2021; 126:668-679. [PMID: 34259043 DOI: 10.1152/jn.00277.2021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Activation of renal sensory nerves by chemo- and mechanosensitive stimuli produces changes in efferent sympathetic nerve activity (SNA) and arterial blood pressure (ABP). Anesthesia and sex influence autonomic function and cardiovascular hemodynamics, but it is unclear to what extent anesthesia and sex impact SNA and ABP responses to renal sensory stimuli. We measured renal, splanchnic, and lumbar SNA and ABP in male and female Sprague-Dawley rats during contralateral renal infusion of capsaicin and bradykinin or during elevation in renal pelvic pressure. Responses were evaluated with a decerebrate preparation or Inactin, urethane, or isoflurane anesthesia. Intrarenal arterial infusion of capsaicin (0.1-30.0 μM) increased renal SNA, splanchnic SNA, or ABP but decreased lumbar SNA in the Inactin group. Intrarenal arterial infusion of bradykinin (0.1-30.0 μM) increased renal SNA, splanchnic SNA, and ABP but decreased lumbar SNA in the Inactin group. Elevated renal pelvic pressure (0-20 mmHg, 30 s) significantly increased renal SNA and splanchnic SNA but not lumbar SNA in the Inactin group. In marked contrast, SNA and ABP responses to every renal stimulus were severely blunted in the urethane and decerebrate groups and absent in the isoflurane group. In the Inactin group, the magnitude of SNA responses to chemo- and mechanosensory stimuli were not different between male and female rats. Thus, chemo- and mechanosensitive stimuli produce differential changes in renal, splanchnic, and lumbar SNA. Experimentally, future investigations should consider Inactin anesthesia to examine sympathetic and hemodynamic responses to renal sensory stimuli.NEW & NOTEWORTHY The findings highlight the impact of anesthesia, and to a lesser extent sex, on sympathetic efferent and hemodynamic responses to chemosensory and mechanosensory renal stimuli. Sympathetic nerve activity (SNA) and arterial blood pressure (ABP) responses were present in Inactin-anesthetized rats but largely absent in decerebrate, isoflurane, or urethane preparations. Renal chemosensory stimuli differentially changed SNA: renal and splanchnic SNA increased, but lumbar SNA decreased. Future investigations should consider Inactin anesthesia to study SNA and hemodynamic responses to renal sensory nerve activation.
Collapse
Affiliation(s)
- Leon J DeLalio
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Sean D Stocker
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| |
Collapse
|
42
|
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] [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.
Collapse
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.
| |
Collapse
|
43
|
Rodionova K, Hilgers KF, Rafii-Tabrizi S, Doellner J, Cordasic N, Linz P, Karl AL, Ott C, Schmieder RE, Schiffer M, Amann K, Veelken R, Ditting T. Responsiveness of afferent renal nerve units in renovascular hypertension in rats. Pflugers Arch 2021; 473:1617-1629. [PMID: 34232378 PMCID: PMC8433106 DOI: 10.1007/s00424-021-02591-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 05/12/2021] [Accepted: 06/03/2021] [Indexed: 12/01/2022]
Abstract
Previous data suggest that renal afferent nerve activity is increased in hypertension exerting sympathoexcitatory effects. Hence, we wanted to test the hypothesis that in renovascular hypertension, the activity of dorsal root ganglion (DRG) neurons with afferent projections from the kidneys is augmented depending on the degree of intrarenal inflammation. For comparison, a nonhypertensive model of mesangioproliferative nephritis was investigated. Renovascular hypertension (2-kidney, 1-clip [2K1C]) was induced by unilateral clipping of the left renal artery and mesangioproliferative glomerulonephritis (anti-Thy1.1) by IV injection of a 1.75-mg/kg BW OX-7 antibody. Neuronal labeling (dicarbocyanine dye [DiI]) in all rats allowed identification of renal afferent dorsal root ganglion (DRG) neurons. A current clamp was used to characterize neurons as tonic (sustained action potential [AP] firing) or phasic (1–4 AP) upon stimulation by current injection. All kidneys were investigated using standard morphological techniques. DRG neurons exhibited less often tonic response if in vivo axonal input from clipped kidneys was received (30.4% vs. 61.2% control, p < 0.05). However, if the nerves to the left clipped kidneys were cut 7 days prior to investigation, the number of tonic renal neurons completely recovered to well above control levels. Interestingly, electrophysiological properties of neurons that had in vivo axons from the right non-clipped kidneys were not distinguishable from controls. Renal DRG neurons from nephritic rats also showed less often tonic activity upon current injection (43.4% vs. 64.8% control, p < 0.05). Putative sympathoexcitatory and impaired sympathoinhibitory renal afferent nerve fibers probably contribute to increased sympathetic activity in 2K1C hypertension.
Collapse
Affiliation(s)
- Kristina Rodionova
- Department of Internal Medicine 4 - Nephrology and Hypertension, Friedrich-Alexander University Erlangen, Erlangen, Germany
| | - Karl F Hilgers
- Department of Internal Medicine 4 - Nephrology and Hypertension, Friedrich-Alexander University Erlangen, Erlangen, Germany
| | - Salman Rafii-Tabrizi
- Department of Internal Medicine 4 - Nephrology and Hypertension, Friedrich-Alexander University Erlangen, Erlangen, Germany
| | - Johannes Doellner
- Department of Internal Medicine 4 - Nephrology and Hypertension, Friedrich-Alexander University Erlangen, Erlangen, Germany
| | - Nada Cordasic
- Department of Internal Medicine 4 - Nephrology and Hypertension, Friedrich-Alexander University Erlangen, Erlangen, Germany
| | - Peter Linz
- Department of Radiology, Friedrich-Alexander University Erlangen, Erlangen, Germany
| | - Anna-Lena Karl
- Department of Internal Medicine 4 - Nephrology and Hypertension, Friedrich-Alexander University Erlangen, Erlangen, Germany
| | - Christian Ott
- Department of Internal Medicine 4 - Nephrology and Hypertension, Friedrich-Alexander University Erlangen, Erlangen, Germany.,Department of Internal Medicine 4 - Nephrology and Hypertension, Paracelsus Private Medical School Nuremberg, Nuremberg, Germany
| | - Roland E Schmieder
- Department of Internal Medicine 4 - Nephrology and Hypertension, Friedrich-Alexander University Erlangen, Erlangen, Germany
| | - Mario Schiffer
- Department of Internal Medicine 4 - Nephrology and Hypertension, Friedrich-Alexander University Erlangen, Erlangen, Germany
| | - Kerstin Amann
- Department of Nephropathology, Friedrich-Alexander University Erlangen, Erlangen, Germany
| | - Roland Veelken
- Department of Internal Medicine 4 - Nephrology and Hypertension, Friedrich-Alexander University Erlangen, Erlangen, Germany. .,Department of Radiology, Friedrich-Alexander University Erlangen, Erlangen, Germany.
| | - Tilmann Ditting
- Department of Internal Medicine 4 - Nephrology and Hypertension, Friedrich-Alexander University Erlangen, Erlangen, Germany.,Department of Internal Medicine 4 - Nephrology and Hypertension, Paracelsus Private Medical School Nuremberg, Nuremberg, Germany
| |
Collapse
|
44
|
Liang B, Liang Y, Li R, Gu N. Effect of renal denervation on long-term outcomes in patients with resistant hypertension. Cardiovasc Diabetol 2021; 20:117. [PMID: 34090434 PMCID: PMC8180124 DOI: 10.1186/s12933-021-01309-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Accepted: 05/28/2021] [Indexed: 12/13/2022] Open
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.
Collapse
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.
| |
Collapse
|
45
|
Weber MA, Osborn JW. Improved Understanding of Renal Nerve Anatomy: An Opportunity to Enhance Denervation Treatment of Hypertension. JACC Cardiovasc Interv 2021; 14:316-318. [PMID: 33541542 DOI: 10.1016/j.jcin.2020.11.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 10/27/2020] [Accepted: 11/03/2020] [Indexed: 12/29/2022]
Affiliation(s)
- Michael A Weber
- Division of Cardiovascular Medicine, State University of New York, Downstate College of Medical, Brooklyn, New York, USA.
| | - John W Osborn
- Department of Surgery, University of Minnesota, Minneapolis, Minnesota, USA
| |
Collapse
|
46
|
Abstract
Dr Irvine Page proposed the Mosaic Theory of Hypertension in the 1940s advocating that hypertension is the result of many factors that interact to raise blood pressure and cause end-organ damage. Over the years, Dr Page modified his paradigm, and new concepts regarding oxidative stress, inflammation, genetics, sodium homeostasis, and the microbiome have arisen that allow further refinements of the Mosaic Theory. A constant feature of this approach to understanding hypertension is that the various nodes are interdependent and that these almost certainly vary between experimental models and between individuals with hypertension. This review discusses these new concepts and provides an introduction to other reviews in this compendium of Circulation Research.
Collapse
Affiliation(s)
- David G. Harrison
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center
| | - Thomas M. Coffman
- Cardiovascular and Metabolic Disorders Research Program, Duke-National University of Singapore Medical School
| | | |
Collapse
|
47
|
Pestana-Oliveira N, Nahey DB, Hartson R, Weber B, Johnson TJ, Collister JP. DOCA-salt hypertension and the role of the OVLT-sympathetic-gut microbiome axis. Clin Exp Pharmacol Physiol 2021; 48:490-497. [PMID: 33462863 PMCID: PMC11078564 DOI: 10.1111/1440-1681.13457] [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: 09/02/2020] [Revised: 09/02/2020] [Accepted: 12/19/2020] [Indexed: 11/29/2022]
Abstract
Hypertension is a multifaceted condition influenced by genetic and environmental factors and estimated to cause 9.4 million deaths globally every year. Recently, there has been growing interest in understanding the gut microbe-host interaction in the maintenance of health or disease states, but relatively few studies have shown an association between the gut microbiome and specific types of hypertension. The deoxycorticosterone acetate (DOCA)-salt model of hypertension in rats is known to have a neurogenic component linked to increased sympathetic nervous system activity. As such, our lab has recently shown the hypertensive response in DOCA treated rats requires an intact organum vasculosum of the lamina terminalis (OVLT), a central hypothalamic circumventricular organ. Currently, we hypothesize the OVLT mediates changes in the gut microbiome associated with concomitant hypertension. Herein, we report that the hypertensive effects of DOCA-salt treatment were significantly attenuated throughout the 24-hour day/night cycle in OLVT lesioned rats on days 1, 3, and 9-21 of DOCA treatment compared with sham rats. Increased blood pressure (BP) in DOCA-salt treated rats was accompanied by specific changes in regional gut microbial populations yet was mitigated and offset by lesion of the OVLT. Furthermore, bacterial populations in OVLT-lesioned rats with attenuated hypertension more closely resembled those in normal control rats. We conclude that DOCA-salt hypertension is associated with specific microbiome changes in the gut, and the attenuated hypertensive effects of DOCA-salt in OVLT-lesioned rats is mediated in part through counteracting changes in these bacterial populations.
Collapse
Affiliation(s)
- Nayara Pestana-Oliveira
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
| | - David B Nahey
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
| | - Rochelle Hartson
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
| | - Bonnie Weber
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
| | - Timothy J Johnson
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
| | - John P Collister
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
| |
Collapse
|
48
|
Yang T, Chakraborty S, Mandal J, Mei X, Joe B. Microbiota and Metabolites as Factors Influencing Blood Pressure Regulation. Compr Physiol 2021; 11:1731-1757. [PMID: 33792901 DOI: 10.1002/cphy.c200009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The study of microbes has rapidly expanded in recent years due to a surge in our understanding that humans host a plethora of commensal microbes, which reside in their bodies and depending upon their composition, contribute to either normal physiology or pathophysiology. This article provides a general foundation for learning about host-commensal microbial interactions as an emerging area of research. The article is divided into two sections. The first section is dedicated to introducing commensal microbiota and its known effects on the host. The second section is on metabolites, which are biochemicals that the host and the microbes use for bi-directional communication with each other. Together, the sections review what is known about how microbes interact with the host to impact cardiovascular physiology, especially blood pressure regulation. © 2021 American Physiological Society. Compr Physiol 11:1731-1757, 2021.
Collapse
Affiliation(s)
- Tao Yang
- Center for Hypertension and Precision Medicine and Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Saroj Chakraborty
- Center for Hypertension and Precision Medicine and Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Juthika Mandal
- Center for Hypertension and Precision Medicine and Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Xue Mei
- Center for Hypertension and Precision Medicine and Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Bina Joe
- Center for Hypertension and Precision Medicine and Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| |
Collapse
|
49
|
Neurogenic substance P-influences on action potential production in afferent neurons of the kidney? Pflugers Arch 2021; 473:633-646. [PMID: 33786667 PMCID: PMC8049925 DOI: 10.1007/s00424-021-02552-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 03/01/2021] [Accepted: 03/03/2021] [Indexed: 12/23/2022]
Abstract
We recently showed that a substance P (SP)–dependent sympatho-inhibitory mechanism via afferent renal nerves is impaired in mesangioproliferative nephritis. Therefore, we tested the hypothesis that SP released from renal afferents inhibits the action potential (AP) production in their dorsal root ganglion (DRG) neurons. Cultured DRG neurons (Th11-L2) were investigated in current clamp mode to assess AP generation during both TRPV1 stimulation by protons (pH 6) and current injections with and without exposure to SP (0.5 µmol) or CGRP (0.5 µmol). Neurons were classified as tonic (sustained AP generation) or phasic (≤ 4 APs) upon current injection; voltage clamp experiments were performed for the investigation of TRPV1-mediated inward currents due to proton stimulation. Superfusion of renal neurons with protons and SP increased the number of action potentials in tonic neurons (9.6 ± 5 APs/10 s vs. 16.9 ± 6.1 APs/10 s, P < 0.05, mean ± SD, n = 7), while current injections with SP decreased it (15.2 ± 6 APs/600 ms vs. 10.2 ± 8 APs/600 ms, P < 0.05, mean ± SD, n = 29). Addition of SP significantly reduced acid-induced TRPV1-mediated currents in renal tonic neurons (− 518 ± 743 pA due to pH 6 superfusion vs. − 82 ± 50 pA due to pH 6 with SP superfusion). In conclusion, SP increased action potential production via a TRPV1-dependent mechanism in acid-sensitive renal neurons. On the other hand, current injection in the presence of SP led to decreased action potential production. Thus, the peptide SP modulates signaling pathways in renal neurons in an unexpected manner leading to both stimulation and inhibition of renal neuronal activity in different (e.g., acidic) environmental contexts.
Collapse
|
50
|
Selective afferent renal denervation mitigates renal and splanchnic sympathetic nerve overactivity and renal function in chronic kidney disease-induced hypertension. J Hypertens 2021; 38:765-773. [PMID: 31764582 DOI: 10.1097/hjh.0000000000002304] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Clinical and experimental evidence have shown that renal denervation, by removing both the sympathetic and afferent nerves, improves arterial hypertension and renal function in chronic kidney disease (CKD). Given the key role of renal sympathetic innervation in maintaining sodium and water homeostasis, studies have indicated that the total removal of renal nerves leads to impaired compensatory mechanisms during hemodynamic challenges. METHOD In the present study, we hypothesized that afferent (or sensory) fibers from the diseased kidney contribute to sympathetic overactivation to the kidney and other target organ, such as the splanchnic region, contributing to hypertension in CKD. We used a method to remove selectively the afferent renal fibers (periaxonal application of 33 mmol/l capsaicin) in a rat model of CKD, the 5/6 nephrectomy. RESULTS Three weeks after afferent renal denervation (ARD), we found a decrease in mean arterial pressure (∼15%) and normalization in renal and splanchnic sympathetic nerve hyperactivity in the CKD group. Interestingly, intrarenal renin--angiotensin system, as well as renal fibrosis and function and proteinuria were improved after ARD in CKD rats. CONCLUSION The findings demonstrate that afferent fibers contribute to the maintenance of arterial hypertension and reduced renal function that are likely to be mediated by increased sympathetic nerve activity to the renal territory as well as to other target organs in CKD.
Collapse
|