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Schrankl J, Fuchs M, Broeker K, Daniel C, Kurtz A, Wagner C. Localization of angiotensin II type 1 receptor gene expression in rodent and human kidneys. Am J Physiol Renal Physiol 2021; 320:F644-F653. [PMID: 33615887 DOI: 10.1152/ajprenal.00550.2020] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The kidneys are an important target for angiotensin II (ANG II). In adult kidneys, the effects of ANG II are mediated mainly by ANG II type 1 (AT1) receptors. AT1 receptor expression has been reported for a variety of different cell types within the kidneys, suggesting a broad spectrum of actions for ANG II. Since there have been heterogeneous results in the literature regarding the intrarenal distribution of AT1 receptors, this study aimed to obtain a comprehensive overview about the localization of AT1 receptor expression in mouse, rat, and human kidneys. Using the cell-specific and high-resolution RNAscope technique, we performed colocalization experiments with various cell markers to specifically discriminate between different segments of the tubular and vascular system. Overall, we found a similar pattern of AT1 mRNA expression in mouse, rat, and human kidneys. AT1 receptors were detected in mesangial cells and renin-producing cells. In addition, AT1 mRNA was found in interstitial cells of the cortex and outer medulla. In rodents, late afferent and early efferent arterioles expressed AT1 receptor mRNA, but larger vessels of the investigated species showed no AT1 expression. Tubular expression of AT1 mRNA was species dependent with a strong expression in proximal tubules of mice, whereas expression was undetectable in human tubular cells. These findings suggest that the (juxta)glomerular area and tubulointerstitium are conserved expression sites for AT1 receptors across species and might present the main target sites for ANG II in adult human and rodent kidneys.NEW & NOTEWORTHY Angiotensin II (ANG II) type 1 (AT1) receptors are essential for mediating the effects of ANG II in the kidneys. This study aimed to obtain a comprehensive overview about the cell-specific localization of AT1 receptor expression in rodent and human kidneys using the novel RNAscope technique. We found that the conserved AT1 receptor mRNA expression sites across species are the (juxta)glomerular areas and tubulointerstitium, which might present main target sites for ANG II in adult human and rodent kidneys.
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Affiliation(s)
- Julia Schrankl
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Michaela Fuchs
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Katharina Broeker
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Christoph Daniel
- Department of Nephropathology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Armin Kurtz
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Charlotte Wagner
- Institute of Physiology, University of Regensburg, Regensburg, Germany
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Sparks MA, Crowley SD, Gurley SB, Mirotsou M, Coffman TM. Classical Renin-Angiotensin system in kidney physiology. Compr Physiol 2015; 4:1201-28. [PMID: 24944035 DOI: 10.1002/cphy.c130040] [Citation(s) in RCA: 353] [Impact Index Per Article: 39.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The renin-angiotensin system has powerful effects in control of the blood pressure and sodium homeostasis. These actions are coordinated through integrated actions in the kidney, cardiovascular system and the central nervous system. Along with its impact on blood pressure, the renin-angiotensin system also influences a range of processes from inflammation and immune responses to longevity. Here, we review the actions of the "classical" renin-angiotensin system, whereby the substrate protein angiotensinogen is processed in a two-step reaction by renin and angiotensin converting enzyme, resulting in the sequential generation of angiotensin I and angiotensin II, the major biologically active renin-angiotensin system peptide, which exerts its actions via type 1 and type 2 angiotensin receptors. In recent years, several new enzymes, peptides, and receptors related to the renin-angiotensin system have been identified, manifesting a complexity that was previously unappreciated. While the functions of these alternative pathways will be reviewed elsewhere in this journal, our focus here is on the physiological role of components of the "classical" renin-angiotensin system, with an emphasis on new developments and modern concepts.
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Affiliation(s)
- Matthew A Sparks
- Division of Nephrology, Department of Medicine, Duke University Medical Center, Durham, North Carolina
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Kandalam U, Palanisamy M, Clark MA. Angiotensin II induces cell growth and IL-6 mRNA expression through the JAK2-STAT3 pathway in rat cerebellar astrocytes. JAKSTAT 2013; 1:83-9. [PMID: 24058756 PMCID: PMC3670299 DOI: 10.4161/jkst.19688] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The pleiotrophic effects of angiotensin II (Ang II) play important roles in astrocyte growth and inflammatory responses. We investigated whether Ang II induces astrocyte growth and interleukin-6 (IL-6) mRNA expression in rat cerebellar astrocytes through Janus kinase 2-signal transduction activator of transcription (JAK2-STAT3). Ang II increased JAK2 and STAT3 phosphorylation in a time- and a dose-dependent manner. One hundred nanomolar Ang II induced maximal phosphorylation of both JAK2 and STAT3 between 15 min and 30 min. The Ang II-mediated phosphorylation of both JAK2 and STAT3 was blocked by AG490, a selective JAK2 inhibitor. Losartan, a selective AT1 receptor antagonist, inhibited Ang II-mediated JAK2 and STAT3 phosphorylation, while pretreatment with an AT2 receptor blocker, PD123319, was ineffective. Ang II increased the mRNA expression of IL-6 in a concentration-and time-dependent manner. Maximal IL-6 mRNA expression occurred with 100 nM Ang II, and the peak effect occurred in a biphasic manner at 3 h and between 12 and 24 h. Moreover, pretreatments with AG490 attenuated Ang II-induced IL-6 mRNA levels, and Ang II-induced astrocyte growth. This study has demonstrated that Ang II induced the phosphorylation of both JAK2 and STAT3 via the AT1 receptor in cerebellar astrocytes. In addition, our results suggest that JAK2 and STAT3 are upstream signals that mediate Ang II-induced IL-6 mRNA expression and astrocyte growth. These findings represent a novel non-classical mechanism of Ang II signaling in cerebellar astrocytes.
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Affiliation(s)
- Umadevi Kandalam
- Department of Pediatric Dentistry; College of Dental Medicine; Nova Southeastern University; Fort Lauderdale, FL USA
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Yugandhar VG, Clark MA. Angiotensin III: a physiological relevant peptide of the renin angiotensin system. Peptides 2013; 46:26-32. [PMID: 23692861 DOI: 10.1016/j.peptides.2013.04.014] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 04/23/2013] [Accepted: 04/27/2013] [Indexed: 01/02/2023]
Abstract
The renin angiotensin system (RAS) is a peptide hormone system that plays an important role in the pathophysiology of various diseases, including congestive heart failure, hypertension, myocardial infarction, and diabetic nephropathy. This has led researchers to focus extensively on this system, leading to the discovery of various peptides, peptidases, receptors and signal transduction mechanisms intrinsic to the RAS. Angiotensinogen (AGT), angiotensin (Ang) II, Ang III, Ang IV, and Ang-(1-7) are the main biologically active peptides of RAS. However, most of the available studies have focused on Ang II as the likely key peptide from the RAS that directly and indirectly regulates physiological functions leading to pathological conditions. However, data from recent studies suggest that Ang III may produce physiologically relevant effects that are similar to those produced by Ang II. Hence, this review focuses on Ang III and the myriad of physiological effects that it produces in the body.
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Affiliation(s)
- Vudhya G Yugandhar
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, 3200 South University Drive, Fort Lauderdale, FL 33328, USA
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Small but powerful: short peptide hormones and their role in autoimmune inflammation. J Neuroimmunol 2009; 217:1-7. [PMID: 19748684 DOI: 10.1016/j.jneuroim.2009.08.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2009] [Accepted: 08/19/2009] [Indexed: 12/31/2022]
Abstract
In the recent years, it has become increasingly clear that the immune response is also influenced by mediators which were first discovered as regulators in the nervous or also cardiovascular system. Here, small peptide hormones may play an important role. Kinins like bradykinins act on the endothelium and play a role for trafficking of lymphocytes over the blood-brain barrier. Neuropeptides like vasoactive intestinal peptide or neuropeptide Y also directly act on T cells and favour the differentiation of Th2 cells or regulatory T cell populations. Recently, the renin-angiotensin system (RAS) came into the focus of interest. Inhibition of the RAS at different levels may influence autoimmune responses and involve T cells as well as antigen-presenting cells, probably via different signalling pathways. Inhibitors of angiotensin converting enzyme and antagonists of the angiotensin 1 receptors are used in the treatment of hypertension, kidney disease or stroke by millions of people worldwide. These inexpensive and safe pharmaceuticals may also represent an interesting and innovative approach for the (combination) treatment of autoimmune diseases like multiple sclerosis.
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Abstract
The renin-angiotensin system (RAS) is a master regulator of blood pressure and fluid homeostasis. Because RAS components are expressed in several tissues that may influence blood pressure, studies using conventional gene targeting to globally interrupt the RAS have not determined the contributions of angiotensin II receptor type 1 (AT(1)) receptors in specific tissue pools to blood pressure regulation and tissue injury. Recent experiments using kidney cross-transplantation and mice lacking the dominant murine AT(1) receptor isoform, AT(1A), have demonstrated that 1) AT(1) receptors inside and outside the kidney make equivalent contributions to normal blood pressure homeostasis, 2) activation of renal AT(1) receptors is required for the development of angiotensin II-dependent hypertension, and 3) this blood pressure elevation rather than activation of AT(1) receptors in the heart drives angiotensin II-induced cardiac hypertrophy. These findings, together with previous experiments, confirm the kidney's critical role in the pathogenesis of hypertension and its complications.
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Clark MA, Gonzalez N. Angiotensin II stimulates rat astrocyte mitogen-activated protein kinase activity and growth through EGF and PDGF receptor transactivation. ACTA ACUST UNITED AC 2007; 144:115-22. [PMID: 17688958 DOI: 10.1016/j.regpep.2007.07.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Revised: 07/03/2007] [Accepted: 07/04/2007] [Indexed: 10/23/2022]
Abstract
We showed that the intracellular tyrosine kinases src and pyk2 mediate angiotensin II (Ang II) stimulation of growth and ERK1/2 mitogen-activated protein (MAP) kinase phosphorylation in astrocytes. In this study, we investigated whether the membrane-bound receptor tyrosine kinases platelet-derived growth factor (PDGF) and epidermal growth factor (EGF) receptors mediate Ang II stimulation of ERK1/2 and astrocyte growth. Ang II significantly stimulated PDGF and EGF receptors in a dose- and time-dependent manner. The PDGF receptor and the EGF receptor were maximally stimulated with 100 nM Ang II (0.98+/-0.18- and 4.4+/-1.4-fold above basal, respectively). This stimulation occurred as early as 5 min, and was sustained for at least 15 min for both receptor tyrosine kinases. Moreover, 1 microM AG1478 and 0.25 microM PDGFRInhib attenuated Ang II stimulation of the EGF and PDGF receptors, respectively. Ang II-induced phosphorylation of ERK1/2 and astrocyte growth was mediated by both PDGF and EGF receptors. This report also provides novel findings that co-inhibiting EGF and PDGF receptors had a greater effect to decrease Ang II-induced ERK1/2 (90% versus 49% and 71% with PDGF receptor and EGF receptor inhibition, respectively), and astrocyte growth (60% versus 10% and 32% with PDGF receptor and EGF receptor inhibition, respectively). In conclusion we showed in astrocytes that the PDGF and the EGF receptors mediate Ang II-induced ERK1/2 phosphorylation and astrocyte growth and that these two receptors may exhibit synergism to regulate effects of the peptide in these cells.
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Affiliation(s)
- Michelle A Clark
- Department of Pharmaceutical and Administrative Sciences, College of Pharmacy, Cardiovascular and Metabolic Research Unit, Nova Southeastern University, 3200 South University Drive, Fort Lauderdale, FL 33328, United States.
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Abstract
The renin-angiotensin system (RAS) is a critical regulator of blood pressure and fluid homeostasis. Components of the RAS, including renin, angiotensin-converting enzyme (ACE), and angiotensin type 1 (AT1) receptors, are expressed throughout the body in tissues that may impact blood pressure control. Blocking actions of individual components of the RAS lowers blood pressure. Although it has been suggested that control of sodium excretion by the kidney is the dominant mechanism for blood pressure regulation by the RAS, pharmacologic antagonists or conventional gene targeting experiments globally interrupt the RAS and cannot discriminate its actions in the kidney from other tissue compartments. Recent experiments using kidney cross-transplantation and genetically engineered mice have confirmed a major role for angiotensin II acting via AT1 receptors in the kidney in hypertension. These actions of renal AT1 receptors are required for the development of angiotensin II-dependent hypertension and cardiac hypertrophy. These findings, with previous experiments, clearly establish the critical role of the kidney in the pathogenesis of hypertension and its cardiovascular complications.
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Crowley SD, Gurley SB, Coffman TM. AT1 Receptors and Control of Blood Pressure: The Kidney and More…. Trends Cardiovasc Med 2007; 17:30-4. [PMID: 17210476 DOI: 10.1016/j.tcm.2006.11.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Revised: 10/14/2006] [Accepted: 11/02/2006] [Indexed: 11/28/2022]
Abstract
The renin-angiotensin system (RAS) is a critical regulator of blood pressure and fluid homeostasis. The components of the RAS including renin, angiotensin-converting enzyme, and angiotensin receptors are expressed throughout the body in tissues that may impact blood pressure control. Blocking actions of individual components of the RAS including renin, angiotensin-converting enzyme, or the type 1 (AT(1)) receptor lowers blood pressure. Although it has been suggested that control of sodium excretion by the kidney is the dominant mechanism for blood pressure regulation by the RAS, pharmacologic antagonists or conventional gene-targeting experiments globally interrupt the RAS and cannot discriminate its actions in the kidney from other tissue compartments. Recent experiments with the use of kidney cross-transplantation and genetically engineered mice suggest independent and equivalent effects of angiotensin II acting via AT(1) receptors in the kidney and in extrarenal tissues to maintain the normal level of blood pressure. However, the nature and relative contributions of these actions may differ in hypertension.
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Affiliation(s)
- Steven D Crowley
- Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, Durham, NC 27710, USA
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Crowley SD, Gurley SB, Oliverio MI, Pazmino AK, Griffiths R, Flannery PJ, Spurney RF, Kim HS, Smithies O, Le TH, Coffman TM. Distinct roles for the kidney and systemic tissues in blood pressure regulation by the renin-angiotensin system. J Clin Invest 2005; 115:1092-9. [PMID: 15841186 PMCID: PMC1070417 DOI: 10.1172/jci23378] [Citation(s) in RCA: 242] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2004] [Accepted: 01/04/2005] [Indexed: 01/13/2023] Open
Abstract
Angiotensin II, acting through type 1 angiotensin (AT(1)) receptors, has potent effects that alter renal excretory mechanisms. Control of sodium excretion by the kidney has been suggested to be the critical mechanism for blood pressure regulation by the renin-angiotensin system (RAS). However, since AT(1) receptors are ubiquitously expressed, precisely dissecting their physiological actions in individual tissue compartments including the kidney with conventional pharmacological or gene targeting experiments has been difficult. Here, we used a cross-transplantation strategy and AT(1A) receptor-deficient mice to demonstrate distinct and virtually equivalent contributions of AT(1) receptor actions in the kidney and in extrarenal tissues to determining the level of blood pressure. We demonstrate that regulation of blood pressure by extrarenal AT(1A) receptors cannot be explained by altered aldosterone generation, which suggests that AT(1) receptor actions in systemic tissues such as the vascular and/or the central nervous systems make nonredundant contributions to blood pressure regulation. We also show that interruption of the AT(1) receptor-mediated short-loop feedback in the kidney is not sufficient to explain the marked stimulation of renin production induced by global AT(1) receptor deficiency or by receptor blockade. Instead, the renin response seems to be primarily determined by renal baroreceptor mechanisms triggered by reduced blood pressure. Thus, the regulation of blood pressure by the RAS is mediated by AT(1) receptors both within and outside the kidney.
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Affiliation(s)
- Steven D Crowley
- Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, Durham, North Carolina 27705, USA
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Crowley SD, Gurley SB, Oliverio MI, Pazmino AK, Griffiths R, Flannery PJ, Spurney RF, Kim HS, Smithies O, Le TH, Coffman TM. Distinct roles for the kidney and systemic tissues in blood pressure regulation by the renin-angiotensin system. J Clin Invest 2005. [PMID: 15841186 DOI: 10.1172/jci200523378] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Angiotensin II, acting through type 1 angiotensin (AT(1)) receptors, has potent effects that alter renal excretory mechanisms. Control of sodium excretion by the kidney has been suggested to be the critical mechanism for blood pressure regulation by the renin-angiotensin system (RAS). However, since AT(1) receptors are ubiquitously expressed, precisely dissecting their physiological actions in individual tissue compartments including the kidney with conventional pharmacological or gene targeting experiments has been difficult. Here, we used a cross-transplantation strategy and AT(1A) receptor-deficient mice to demonstrate distinct and virtually equivalent contributions of AT(1) receptor actions in the kidney and in extrarenal tissues to determining the level of blood pressure. We demonstrate that regulation of blood pressure by extrarenal AT(1A) receptors cannot be explained by altered aldosterone generation, which suggests that AT(1) receptor actions in systemic tissues such as the vascular and/or the central nervous systems make nonredundant contributions to blood pressure regulation. We also show that interruption of the AT(1) receptor-mediated short-loop feedback in the kidney is not sufficient to explain the marked stimulation of renin production induced by global AT(1) receptor deficiency or by receptor blockade. Instead, the renin response seems to be primarily determined by renal baroreceptor mechanisms triggered by reduced blood pressure. Thus, the regulation of blood pressure by the RAS is mediated by AT(1) receptors both within and outside the kidney.
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Affiliation(s)
- Steven D Crowley
- Division of Nephrology, Department of Medicine, Duke University and Durham VA Medical Centers, Durham, North Carolina 27705, USA
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Davisson RL. Physiological genomic analysis of the brain renin-angiotensin system. Am J Physiol Regul Integr Comp Physiol 2003; 285:R498-511. [PMID: 12909574 DOI: 10.1152/ajpregu.00190.2003] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The brain renin-angiotensin system (RAS) has long been considered pivotal in cardiovascular regulation and important in the pathogenesis of hypertension and heart failure. However, despite more than 30 years of study, the brain RAS continues to defy explanation. Our lack of understanding of how the brain RAS is organized at the cellular and regional levels has made it difficult to resolve long-sought questions of how ANG II is produced in the brain and the precise mechanisms by which it exerts its actions. A major reason for this is the difficulty in experimentally dissecting the brain RAS at the regional, cellular, and whole organism levels. Recently, we and others developed a series of molecular tools for selective manipulation of the murine brain RAS, in parallel with technologies for integrative analysis of cardiovascular and volume homeostasis in the conscious mouse. This review, based in part on a lecture given in conjunction with the American Physiological Society Young Investigator Award in Regulatory and Integrative Physiology (Water and Electrolyte Homeostasis Section), outlines the physiological genomics strategy that we have taken in an effort to unravel some of the complexities of this system. It also summarizes the principles, progress, and prospects for a better understanding of the brain RAS in health and disease.
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Affiliation(s)
- Robin L Davisson
- Dept. of Anatomy and Cell Biology, 1-251 Bowen Science Bldg., The Univ. of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, USA.
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