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Renal Denervation Influences Angiotensin II Types 1 and 2 Receptors. Int J Nephrol 2022; 2022:8731357. [PMID: 36262553 PMCID: PMC9576444 DOI: 10.1155/2022/8731357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 09/05/2022] [Accepted: 09/12/2022] [Indexed: 11/17/2022] Open
Abstract
The sympathetic and renin-angiotensin systems (RAS) are two critical regulatory systems in the kidney which affect renal hemodynamics and function. These two systems interact with each other so that angiotensin II (Ang II) has the presynaptic effect on the norepinephrine secretion. Another aspect of this interaction is that the sympathetic nervous system affects the function and expression of local RAS receptors, mainly Ang II receptors. Therefore, in many pathological conditions associated with an increased renal sympathetic tone, these receptors' expression changes and renal denervation can normalize these changes and improve the diseases. It seems that the renal sympathectomy can alter Ang II receptors expression and the distribution of RAS receptors in the kidneys, which influence renal functions.
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2
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Guo Z, Poglitsch M, Cowley D, Domenig O, McWhinney BC, Ungerer JPJ, Wolley M, Stowasser M. Effects of Ramipril on the Aldosterone/Renin Ratio and the Aldosterone/Angiotensin II Ratio in Patients With Primary Aldosteronism. Hypertension 2020; 76:488-496. [PMID: 32507039 DOI: 10.1161/hypertensionaha.120.14871] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The aldosterone/renin ratio (ARR) is currently considered the most reliable approach for case detection of primary aldosteronism (PA). ACE (Angiotensin-converting enzyme) inhibitors are known to raise renin and lower aldosterone levels, thereby causing false-negative ARR results. Because ACE inhibitors lower angiotensin II levels, we hypothesized that the aldosterone/equilibrium angiotensin II (eqAngII) ratio (AA2R) would remain elevated in PA. Receiver operating characteristic curve analysis involving 60 patients with PA and 40 patients without PA revealed that the AA2R was not inferior to the ARR in screening for PA. When using liquid chromatography-tandem mass spectrometry to measure plasma aldosterone concentration, the predicted optimal AA2R cutoff for PA screening was 8.3 (pmol/L)/(pmol/L). We then compared the diagnostic performance of the AA2R with the ARR among 25 patients with PA administered ramipril (5 mg/day) for 2 weeks. Compared with basally, plasma levels of equilibrium angiotensin I (eqAngI) and direct renin concentration increased significantly (P<0.01 or P<0.05) after ramipril treatment, whereas eqAngII and ACE activity (eqAngII/eqAngI) decreased significantly (P<0.01). The changes of plasma renin activity and plasma aldosterone concentration in the current study were not significant. On day 14, 4 patients displayed false-negative results using ARR_direct renin concentration (plasma aldosterone concentration/direct renin concentration), 3 of whom also showed false-negative ARR_plasma renin activity (plasma aldosterone concentration/plasma renin activity). On day 15, 2 patients still demonstrated false-negative ARR_plasma renin activity, one of whom also showed a false-negative ARR_direct renin concentration. No false-negative AA2R results were observed on either day 14 or 15. In conclusion, compared with ARR which can be affected by ACE inhibitors causing false-negative screening results, the AA2R seems to be superior in detecting PA among subjects receiving ACE inhibitors.
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Affiliation(s)
- Zeng Guo
- From the Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia (Z.G., D.C., M.W., M.S.)
| | | | - Diane Cowley
- From the Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia (Z.G., D.C., M.W., M.S.)
| | - Oliver Domenig
- Attoquant Diagnostics GmbH, Vienna, Austria (M.P., O.D.)
| | - Brett C McWhinney
- Department of Chemical Pathology, Pathology Queensland, Queensland Health, Brisbane, Australia (B.C.M., J.P.J.U.)
| | - Jacobus P J Ungerer
- Department of Chemical Pathology, Pathology Queensland, Queensland Health, Brisbane, Australia (B.C.M., J.P.J.U.).,School of Biomedical Sciences, University of Queensland, Brisbane, Australia (J.P.J.U.)
| | - Martin Wolley
- From the Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia (Z.G., D.C., M.W., M.S.)
| | - Michael Stowasser
- From the Endocrine Hypertension Research Centre, University of Queensland Diamantina Institute, Greenslopes and Princess Alexandra Hospitals, Brisbane, Australia (Z.G., D.C., M.W., M.S.)
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3
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Martins JR, Reichhart N, Kociok N, Stindl J, Foeckler R, Lachmann P, Todorov V, Castrop H, Strauß O. Systemic ß adrenergic stimulation/ sympathetic nerve system stimulation influences intraocular RAS through cAMP in the RPE. Exp Eye Res 2019; 189:107828. [PMID: 31589840 DOI: 10.1016/j.exer.2019.107828] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2019] [Revised: 10/02/2019] [Accepted: 10/03/2019] [Indexed: 10/25/2022]
Abstract
Several lines of evidence support the existence of a renin-angiotensin system (RAS) in the retina that is separated from the blood stream by the retinal pigment epithelium (RPE). Under physiological conditions, increased activity of intraretinal RAS regulates neuronal activity of the retina but patho-physiologically participates in retinal degeneration such as hypertensive or diabetic retinopathy. Interestingly, the RPE appears to be a modulator of intraretinal RAS in response to changes in systemic RAS. As increased systemic RAS activity is associated with increased sympathetic tonus, we investigated whether systemic β-adrenergic stimulation of the RPE also modulates renin expression in the RPE. In vivo, the mouse RPE expresses the β-adrenergic receptor subtypes 1 and 2. Staining of retina sagittal sections showed tyrosine hydroxylase positive nerve endings in the choroid indicating adrenaline/noradrenaline production sites in close proximity to the RPE. Systemic infusion of isoproterenol increased renin expression in the RPE but not in the retina. This increase was sensitive to concomitant systemic application of the angiotensin-2 receptor-type-1 blocker losartan. In vitro analysis of renin gene expression using polarized porcine RPE showed that the activity of the renin promoter can be increased by cAMP stimulation (IBMX/forskolin) but was not influenced by angiotensin-2. Thus, with the identification of the β-adrenergic system we added a new regulator of the retinal RAS with relevance for retinal function and pathology. Furthermore, it appears that the RPE is not only a close interaction partner of the photoreceptors but also a regulator or retinal activity in general.
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Affiliation(s)
- Joana Raquel Martins
- Experimental Ophthalmology, Eye Hospital, University Medical Center Regensburg, Regensburg, Germany
| | - Nadine Reichhart
- Experimental Ophthalmology, Department of Ophthalmology, Charité - Universitätsmedizin Berlin, a Corporate Member of Freie Universität, Humboldt-University, The Berlin Institute of Health, Berlin, Germany
| | - Nobert Kociok
- Experimental Ophthalmology, Department of Ophthalmology, Charité - Universitätsmedizin Berlin, a Corporate Member of Freie Universität, Humboldt-University, The Berlin Institute of Health, Berlin, Germany
| | - Julia Stindl
- Experimental Ophthalmology, Eye Hospital, University Medical Center Regensburg, Regensburg, Germany
| | - Renate Foeckler
- Experimental Ophthalmology, Eye Hospital, University Medical Center Regensburg, Regensburg, Germany
| | - Peter Lachmann
- Laboratory for Experimental Nephrology, Dresden University of Technology, Dresden, Germany
| | - Vladimir Todorov
- Laboratory for Experimental Nephrology, Dresden University of Technology, Dresden, Germany
| | - Hayo Castrop
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Olaf Strauß
- Experimental Ophthalmology, Department of Ophthalmology, Charité - Universitätsmedizin Berlin, a Corporate Member of Freie Universität, Humboldt-University, The Berlin Institute of Health, Berlin, Germany.
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4
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Neubauer B, Schrankl J, Steppan D, Neubauer K, Sequeira-Lopez ML, Pan L, Gomez RA, Coffman TM, Gross KW, Kurtz A, Wagner C. Angiotensin II Short-Loop Feedback: Is There a Role of Ang II for the Regulation of the Renin System In Vivo? Hypertension 2018; 71:1075-1082. [PMID: 29661841 DOI: 10.1161/hypertensionaha.117.10357] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 10/11/2017] [Accepted: 03/19/2018] [Indexed: 11/16/2022]
Abstract
The activity of the renin-angiotensin-aldosterone system is triggered by the release of the protease renin from the kidneys, which in turn is controlled in the sense of negative feedback loops. It is widely assumed that Ang II (angiotensin II) directly inhibits renin expression and secretion via a short-loop feedback by an effect on renin-producing cells (RPCs) mediated by AT1 (Ang II type 1) receptors. Because the concept of such a direct short-loop negative feedback control, which originates mostly from in vitro experiments, has not yet been systematically proven in vivo, we aimed to test the validity of this concept by studying the regulation of renin synthesis and secretion in mice lacking Ang II-AT1 receptors on RPCs. We found that RPCs of the kidney express Ang II-AT1 receptors. Mice with conditional deletion of Ang II-AT1 receptors in RPCs were normal with regard to the number of renin cells, renal renin mRNA, and plasma renin concentrations. Renin expression and secretion of these mice responded to Ang I (angiotensin I)-converting enzyme inhibition and to Ang II infusion like in wild-type (WT) controls. In summary, we did not obtain evidence that Ang II-AT1 receptors on RPCs are of major relevance for the normal regulation of renin expression and secretion in mice. Therefore, we doubt the existence of a direct negative feedback function of Ang II on RPCs.
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Affiliation(s)
- Bjoern Neubauer
- From the Institute of Physiology, University of Regensburg, Germany (B.N., J.S., D.S., K.N., A.K., C.W.)
| | - Julia Schrankl
- From the Institute of Physiology, University of Regensburg, Germany (B.N., J.S., D.S., K.N., A.K., C.W.)
| | - Dominik Steppan
- From the Institute of Physiology, University of Regensburg, Germany (B.N., J.S., D.S., K.N., A.K., C.W.)
| | - Katharina Neubauer
- From the Institute of Physiology, University of Regensburg, Germany (B.N., J.S., D.S., K.N., A.K., C.W.).,Division of Pediatric Hematology and Oncology, Department of Pediatrics and Adolescent Medicine, Medical Center-University of Freiburg, Germany (K.N.)
| | - Maria Luisa Sequeira-Lopez
- Department of Pediatrics, Child Health Research Center, University of Virginia School of Medicine, Charlottesville (M.L.S.-L., R.A.G.)
| | - Li Pan
- Department of Pathology, Brigham and Women's Hospital, Boston, MA (L.P.)
| | - R Ariel Gomez
- Department of Pediatrics, Child Health Research Center, University of Virginia School of Medicine, Charlottesville (M.L.S.-L., R.A.G.)
| | - Thomas M Coffman
- Division of Nephrology, Department of Medicine, Durham Veterans Affairs Medical Centers, Duke University, NC (T.M.C.).,and Department of Molecular and Cellular Biology, Roswell Park Cancer Institute, Buffalo, NY (K.W.G.)
| | - Kenneth W Gross
- and Department of Molecular and Cellular Biology, Roswell Park Cancer Institute, Buffalo, NY (K.W.G.)
| | - Armin Kurtz
- From the Institute of Physiology, University of Regensburg, Germany (B.N., J.S., D.S., K.N., A.K., C.W.)
| | - Charlotte Wagner
- From the Institute of Physiology, University of Regensburg, Germany (B.N., J.S., D.S., K.N., A.K., C.W.)
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5
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Bohlender JM, Nussberger J, Birkhäuser F, Grouzmann E, Thalmann GN, Imboden H. Resetting of renal tissular renin-angiotensin and bradykinin-kallikrein systems after unilateral kidney denervation in rats. Histochem Cell Biol 2017; 147:585-593. [PMID: 28220244 DOI: 10.1007/s00418-017-1543-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/20/2017] [Indexed: 01/11/2023]
Abstract
The renal tissular renin-angiotensin and bradykinin-kallikrein systems control kidney function together with the renal sympathetic innervation but their interaction is still unclear. To further elucidate this relationship, we investigated these systems in rats 6 days after left kidney denervation (DNX, n = 8) compared to sham-operated controls (CTR, n = 8). Plasma renin concentration was unchanged in DNX vs. CTR (p = NS). Kidney bradykinin (BK) and angiotensin (Ang) I and II concentrations decreased bilaterally in DNX vs. CTR rats (~20 to 40%, p < 0.05) together with Ang IV and V concentrations that were extremely low (p = NS). Renin, Ang III and dopamine concentrations decreased by ~25 to 50% and norepinephrine concentrations by 99% in DNX kidneys (p < 0.05) but were unaltered in opposite kidneys. Ang II/I and KA were comparable in DNX, contralateral and CTR kidneys. Ang III/II increased in right vs. DNX or CTR kidneys (40-50%, p < 0.05). Ang II was mainly located in tubular epithelium by immunocytological staining and its cellular distribution was unaffected by DNX. Moreover, the angiotensinergic and catecholaminergic innervation of right kidneys was unchanged vs. CTR. We found an important dependency of tissular Ang and BK levels on the renal innervation that may contribute to the resetting of kidney function after DNX. The DNX-induced peptide changes were not readily explained by kidney KA, renin or plasma Ang I generation. However, tissular peptide metabolism and compartmentalization may have played a central role. The mechanisms behind the concentration changes remain unclear and deserve further clarification.
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Affiliation(s)
- Jürgen M Bohlender
- Institute for Cell Biology, University of Bern, Bern, Switzerland. .,Department of Nephrology, Hypertension and Clinical Pharmacology, Inselspital, Bern University Hospital, University of Bern, Freiburgstr. 4, 3010, Bern, Switzerland.
| | - Jürg Nussberger
- Department of Medicine, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland
| | - Frédéric Birkhäuser
- Department of Urology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Eric Grouzmann
- Service of Biomedicine, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland
| | - George N Thalmann
- Department of Urology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Hans Imboden
- Institute for Cell Biology, University of Bern, Bern, Switzerland
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Castrop H, Höcherl K, Kurtz A, Schweda F, Todorov V, Wagner C. Physiology of Kidney Renin. Physiol Rev 2010; 90:607-73. [PMID: 20393195 DOI: 10.1152/physrev.00011.2009] [Citation(s) in RCA: 189] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The protease renin is the key enzyme of the renin-angiotensin-aldosterone cascade, which is relevant under both physiological and pathophysiological settings. The kidney is the only organ capable of releasing enzymatically active renin. Although the characteristic juxtaglomerular position is the best known site of renin generation, renin-producing cells in the kidney can vary in number and localization. (Pro)renin gene transcription in these cells is controlled by a number of transcription factors, among which CREB is the best characterized. Pro-renin is stored in vesicles, activated to renin, and then released upon demand. The release of renin is under the control of the cAMP (stimulatory) and Ca2+(inhibitory) signaling pathways. Meanwhile, a great number of intrarenally generated or systemically acting factors have been identified that control the renin secretion directly at the level of renin-producing cells, by activating either of the signaling pathways mentioned above. The broad spectrum of biological actions of (pro)renin is mediated by receptors for (pro)renin, angiotensin II and angiotensin-( 1 – 7 ).
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Affiliation(s)
- Hayo Castrop
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Klaus Höcherl
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Armin Kurtz
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Frank Schweda
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Vladimir Todorov
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Charlotte Wagner
- Institute of Physiology, University of Regensburg, Regensburg, Germany
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7
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Cocco G, Ettlin T, Baumeler HR. The effect of amlodipine and enalapril on blood pressure and neurohumoral activation in hypertensive patients with Ribbing's disease (multiple epiphysal dystrophy). Clin Cardiol 2009; 23:109-14. [PMID: 10676602 PMCID: PMC6655105 DOI: 10.1002/clc.4960230208] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In patients with Ribbing's disease (RD)--a form of multiple epiphysal dystrophy--hypertension is frequent, often severe, and accompanied by a relevant cardiac dysfunction. HYPOTHESIS This study was undertaken to evaluate the contribution of the calcium antagonist amlodipine and of the angiotensin-converting-enzyme inhibitor enalapril to blood pressure regulation by studying their effect on neurohormonal activation. METHODS Fifty hypertensive patients with RD were studied. After a placebo run-in period of 4 to 6 weeks, patients were randomly assigned to receive either amlodipine (10 mg once daily) or enalapril (20 mg once daily) for 6 months. RESULTS Both drugs significantly lowered blood pressure. Enalapril did not result in activation of the sympathetic system (as determined by measurement of the plasma norepinephrine level). On the other hand, the hypotensive effect of amlodipine occurred with an increase in heart rate and in the levels of plasma norepinephrine and angiotensin II. CONCLUSION It is unclear whether amlodipine may reduce cardiac dysfunction in patients with RD.
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Affiliation(s)
- G Cocco
- Rehaklinik Rheinfelden, Switzerland
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8
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Krieger MH, Moreira ED, Oliveira EM, Oliveira VLL, Krieger EM, Krieger JE. DISSOCIATION OF BLOOD PRESSURE AND SYMPATHETIC ACTIVATION OF RENIN RELEASE IN SINOAORTIC-DENERVATED RATS. Clin Exp Pharmacol Physiol 2006; 33:471-6. [PMID: 16700880 DOI: 10.1111/j.1440-1681.2006.04389.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
1. Blood pressure (BP) and heart rate (HR) increase 6 and 24 h after sinoaortic baroreceptor denervation (SAD), whereas plasma renin activity (PRA) and renal renin mRNA levels remain unchanged. We postulated that a simultaneous rise in BP could offset the expected activation of renin associated with an increased renal sympathetic discharge secondary to SAD. 2. To test this hypothesis, the increase in BP associated with the onset of SAD was prevented by a continuous infusion of sodium nitroprusside (SNP; 30 microg/kg per h). Changes were measured in five groups of conscious adult male Wistar rats: (i) sham; (ii) SAD; (iii) SAD rats in which the BP was prevented from increasing by infusion of SNP; (iv) sham rats in which the BP was increased by 30% by infusion of phenylephrine (PE; 1.5-2.0 mL/h); and (v) SNP + PE for 3 h by infusion as above. 3. As expected, BP and heart rate (HR) increased significantly following SAD compared with sham rats (152 +/- 4 vs 116 +/- 3 mmHg, respectively, for BP and 503 +/- 6 vs 345 +/- 13 b.p.m., respectively for HR; n = 5; P < 0.05) but remained unchanged when SNP was infused for 3 h (106 +/- 1 mmHg and 455 +/- 9 b.p.m., respectively; n = 5; P < 0.05). 4. Similarly, BP and HR increased with PE infusion compared with PE + SNP (138 +/- 9.9 vs 113 +/- 2.3 mmHg for BP, respectively, and 325 +/- 9 vs 423 +/- 18 b.p.m. for HR, respectively; n = 5; P < 0.05). 5. Plasma renin activity remained unchanged in SAD compared with sham rats (1.67 +/- 0.35 vs 1.05 +/- 0.17 ng angiotensin (Ang) I/mL per h), but increased significantly when hypertension was prevented (5.86 +/- 0.77 ng AngI/mL per h; n = 5; P < 0.05). Renin mRNA levels in the kidneys were unchanged in all groups. 6. These results show that an elevation in BP appears to offset increased renal sympathetic discharge with no change in PRA.
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Affiliation(s)
- Marta H Krieger
- Department of Physiology and Biophysics, Institute of Biology, State University of Campinas, Campinas, SP, Brazil.
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9
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Bucher M, Kees F, Taeger K, Kurtz A. Cytokines down-regulate alpha1-adrenergic receptor expression during endotoxemia. Crit Care Med 2003; 31:566-71. [PMID: 12576967 DOI: 10.1097/01.ccm.0000048621.36569.69] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The reduced pressure response to norepinephrine in septic patients has directed our interest to the regulation of alpha1-adrenergic receptors in vitro and in vivo during conditions mimicking acute sepsis. DESIGN Prospective animal trial followed by a controlled cell culture study. SETTING Laboratory of the Department of Anesthesiology. SUBJECTS Male Sprague-Dawley rats weighing 200 to 250 g and a mesangial cell line. INTERVENTIONS Experimental endotoxemia was induced in rats with lipopolysaccharide, and blood pressure dose-response studies with norepinephrine were performed. Alpha1-receptor gene expression was determined in various organs by a specific RNase protection assay, and tissue concentrations of the proinflammatory cytokines interleukin-1beta and tumor necrosis factor-alpha were measured. Rat renal mesangial cells were incubated with these cytokines or with nitric oxide donors to investigate the regulation of alpha1-adrenergic receptors during severe inflammation on a cellular level. MEASUREMENTS AND MAIN RESULTS The pressor effect of norepinephrine was markedly diminished during endotoxemia. The animals showed down-regulated mRNA levels of alpha1A-, alpha1B- and alpha1D-receptors in all organs investigated, and the tissue concentrations of interleukin-1beta and tumor necrosis factor-alpha were highly increased during experimental endotoxemia. Incubation of cultured rat renal mesangial cells with the cytokines resulted in diminished alpha -receptor gene expression and [3H]prazosin binding capacity, whereas incubation of the cells with nitric oxide donors did not affect alpha1B-receptor expression. In line, blocking of cytokine-induced nitric oxide synthesis by coincubation of mesangial cells with N(G)-nitro-L-arginine methyl ester did not influence cytokine-induced down-regulation of alpha1B-receptors. CONCLUSIONS Our data show that endotoxemia causes a systemic down-regulation of alpha1-receptors on the level of gene expression and suggest that this effect is likely mediated by proinflammatory cytokines in a synergistic but nitric oxide-independent fashion. We propose that this down-regulation of alpha1-adrenergic receptors contributes to the attenuated blood pressure response to norepinephrine and, therefore, to septic circulatory failure in patients.
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Affiliation(s)
- Michael Bucher
- Department of Anesthesiology, University of Regensburg, Germany.
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10
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Seifarth C, Trenkel S, Schobel H, Hahn EG, Hensen J. Influence of antihypertensive medication on aldosterone and renin concentration in the differential diagnosis of essential hypertension and primary aldosteronism. Clin Endocrinol (Oxf) 2002; 57:457-65. [PMID: 12354127 DOI: 10.1046/j.1365-2265.2002.01613.x] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE Antihypertensive drugs influence the neurohumoral cardiovascular system and the concentration of hormones involved in blood pressure regulation. Little is known, however, about the extent to which various antihypertensive drugs influence cardiovascular hormone concentrations and thus disturb the differential diagnosis of hypertension in clinical practice. In this study we compare the impact of different antihypertensive medicaments on the renin-angiotensin-aldosterone system in patients with essential hypertension who are screened for primary aldosteronism. DESIGN AND SUBJECTS We analysed serum aldosterone (SAC) and plasma renin concentration (PRC) in 37 normotensive controls, 144 hypertensive patients with essential hypertension, and 19 patients with primary aldosteronism. Patients were on different treatment regimens such as single drug or combination therapy with beta-blockers, angiotensin-converting enzyme (ACE) inhibitors or angiotensin II subtype 1 (AT1) receptor antagonists, calcium channel blockers, spironolactone and no treatment. RESULTS In patients with essential hypertension, beta-blocker therapy (n = 47) led to a highly significant suppression of renin, whereas serum levels of aldosterone were not significantly altered. ACE inhibitors and AT1 receptor antagonists (n = 55) decreased aldosterone levels only to a minor extent. Calcium channel blockers (n = 23) had no significant influence on SAC or PRC. In patients with primary aldosteronism treated with spironolactone (n = 8), renin escaped suppression and reached very high levels. CONCLUSION Beta-blockers and aldosterone antagonists have the strongest impact on the renin-angiotensin system. The decrease in renin concentration by beta-blockers leads to an increase in the ratio of aldosterone to renin, and thus to false-positive results in patients with essential hypertension. Calcium channel blockers, and probably also ACE inhibitors and AT1 receptor antagonists alone or in combination, may be continued during screening for primary aldosteronism by determination of renin and aldosterone concentration.
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Affiliation(s)
- C Seifarth
- Department of Internal Medicine I, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany
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11
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Höcherl K, Kammerl M, Kees F, Krämer BK, Grobecker HF, Kurtz A. Role of renal nerves in stimulation of renin, COX-2, and nNOS in rat renal cortex during salt deficiency. Am J Physiol Renal Physiol 2002; 282:F478-84. [PMID: 11832429 DOI: 10.1152/ajprenal.00209.2001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
We investigated a possible involvement of the sympathetic nervous system in the parallel increase of renin, cyclooxygenase-2 (COX-2), and neuronal nitric oxide synthase (nNOS) gene expression in the juxtaglomerular apparatus of rat kidneys induced by salt deficiency. Therefore, we determined the effects of renal denervation and the beta-adrenoreceptor antagonist metoprolol (50 mg/kg body wt po, twice a day) on renocortical expression of renin, COX-2, and nNOS in rats fed a low-salt (0.02% wt/wt) diet or treated for 1 wk with ramipril (10 mg/kg body wt) in combination with a low-salt diet. We found that a low-salt diet in combination with ramipril strongly increased renocortical mRNA levels of renin, COX-2, and nNOS 9-, 7-, and 2.5-fold, respectively. Treatment with metoprolol did not change basal expression of the three genes or induction of renin and COX-2 gene expression, while induction of nNOS expression was clearly attenuated. Similarly, unilateral renal denervation attenuated induction of nNOS expression but had no effect on all other parameters. These findings suggest that beta-adrenergic stimulation is not required for stimulation of renin and COX-2 gene expression in the juxtaglomerular apparatus during salt deficiency. However, beta-adrenoreceptor activity or renal nerve activity appears to be required for the full stimulation of nNOS expression by low salt intake or combined with angiotensin-converting enzyme inhibition.
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Affiliation(s)
- K Höcherl
- Department of Pharmacology, University of Regensburg, 93040 Regensburg, Germany.
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12
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Rosnes JS, Valego N, Wang JJ, Perez FM, Rose JC. Renal mRNA response to reduced perfusion pressure conserved despite denervation in mature ovine fetuses. Am J Physiol Regul Integr Comp Physiol 2001; 280:R1830-6. [PMID: 11353689 DOI: 10.1152/ajpregu.2001.280.6.r1830] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We hypothesized that renal denervation in mature ovine fetuses reduces renin mRNA response to 24 h of reduced renal perfusion pressure (RPP). Seven occluder (O) (132.4 ± 1.2 days gestation) and six control (C) (131.5 ± 1.2 days gestation) fetuses underwent left renal denervation. Postoperatively, O fetuses experienced 24 h of reduced RPP by suprarenal aortic occlusion. Femoral arterial blood pressure (FAB) and plasma active renin (pARC) and prorenin (pPRC) concentrations were obtained hourly for 6 h and at h 23 and 24. Renin mRNA was measured by RNase protection assay. We quantitated renin containing glomeruli by immunocytochemistry. Variables were compared by ANOVA. Mean O group FAB reduction from baseline was −6.60 ± 0.41 mmHg. pARC and pPRC increased with occlusion, renal ARC and renal PRC 1 did not increase with occlusion. No effect in renin mRNA or number of positive glomeruli was noted with denervation in the basal state; however, significant increases were noted in response to RPP irrespective of innervation status. In conclusion, 24 h or reduced RPP in mature ovine fetus increases renal renin mRNA and the immunocytochemical expression of renin. This response is conserved despite denervation.
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Affiliation(s)
- J S Rosnes
- Department of Obstetrics and Gynecology, Perinatal Research Laboratories, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA.
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Höcherl K, Färber L, Ladenburger S, Vosshage D, Stratz T, Müller W, Grobecker H. Effect of tropisetron on circulating catecholamines and other putative biochemical markers in serum of patients with fibromyalgia. Scand J Rheumatol Suppl 2001; 113:46-8. [PMID: 11028831 DOI: 10.1080/030097400446634] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
OBJECTIVE The aim of the study was to assess the influence of the 5HT3-receptor antagonist tropisetron on circulating catecholamines as biochemical markers of the activity of the sympathoadrenal system in fibromyalgia. Moreover, serum concentrations of serotonin, somatomedin C, oxytocin, calcitonin-gene-related-peptide, calcitonin and cholecystokinin were assayed as putative markers in pain-related disorders like primary fibromyalgia. METHODS In 96 patients, who met the ACR classification criteria for fibromyalgia, and in 20 sex and age matched controls concentrations of dopamine, noradrenaline, adrenaline, serotonin and tropisetron were assayed in serum by HPLC with electrochemical detection. All other transmitters were determined by ELISA. RESULTS There was with the exception of tropisetron, calcitonin and dopamine, no correlation between doses of tropisetron 5, 10, 15 mg respectively and significant changes in circulating transmitters or other transmitters as putative biochemicals markers in primary fibromyalgia. Regarding the prediction of pain reduction to tropisetron, patients with elevated dopamine and/or reduced plasma 5-HT concentrations tended to show a higher response rate. CONCLUSION Despite these partly disappointing results another prospective pilot study with selected patients vs. age and sex matched controls, double blind and with comparison of other 5HT3-receptor antagonists e.g. dolasetron and granisetron e.g. after i.v. bolus injection is suggested. Still the data obtained in this preliminary paper provide some evidence regarding the present discussion on subgroups of patients with primary fibromyalgia.
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Affiliation(s)
- K Höcherl
- Department of Pharmacology and Clinical Pharmacology, University of Regensburg, Germany.
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Draper ML, Wang J, Valego N, Block WA, Rose JC. Effect of renal denervation on renin gene expression, concentration, and secretion in mature ovine fetus. Am J Physiol Regul Integr Comp Physiol 2000; 279:R263-70. [PMID: 10896890 DOI: 10.1152/ajpregu.2000.279.1.r263] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To determine the role of the renal nerves on renin secretion and expression in the mature ovine fetus, we performed bilateral renal denervation on eight fetuses of time-dated pregnant ewes (126.8 +/- 0.6 days gestation) and compared renin in them to seven fetuses that underwent sham denervation (126.7 +/- 0.6 days gestation). Fetal arterial and venous catheters were implanted, and after 5-7 days of recovery isoproterenol was infused. Plasma active renin was lower in denervated animals than in intact animals under basal conditions and at each dose of isoproterenol. Plasma prorenin levels were lower in denervated fetuses but unaffected by isoproterenol. Denervation did not change renal renin, prorenin, or renin mRNA, but it did block isoproterenol-induced increases in renin mRNA in renocortical cells in vitro. We conclude that the renal nerves are required for renin secretory mechanisms and responsiveness of renin mRNA to beta-adrenergic stimulation but not for the expression of renin in the fetal kidney. We propose that one or more of the factors that maintain renin expression in the perinatal period may be absent or may be replaced by the renal nerves in the adult.
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Affiliation(s)
- M L Draper
- Department of Obstetrics and Gynecology, and the Perinatal Research Laboratories, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA.
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Wagner C, Hinder M, Krämer BK, Kurtz A. Role of renal nerves in the stimulation of the renin system by reduced renal arterial pressure. Hypertension 1999; 34:1101-5. [PMID: 10567189 DOI: 10.1161/01.hyp.34.5.1101] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The aim of this study was to determine the role of renal innervation in the prolonged stimulation of renin secretion and renin synthesis accompanying renal artery stenosis. Male Sprague-Dawley rats, in which the left kidney had been denervated or sham denervated 4 days earlier, received a left renal artery clip (ID 0.2 mm). Plasma renin activity and renin mRNA were assayed 1, 2, or 4 days after clipping. The stimulation of both plasma renin activity and renin mRNA was blunted markedly in the rats with the denervated clipped kidney. The typical suppression of renin mRNA in the intact right kidney, however, was not different between rats with sham-denervated or denervated left kidneys, nor was the increase of blood pressure in response to renal artery clipping different between the experimental groups. To test whether the suppression of renin mRNA in the contralateral kidney was related to the increase of blood pressure, another group of rats with denervated clipped left kidneys was treated additionally with the T-type calcium channel blocker mibefradil (15 mg. kg(-1). d(-1)). Despite blood pressure normalization by mibefradil, plasma renin activities and renin mRNA levels in the clipped denervated kidneys and in the intact right kidneys remained unchanged. These findings suggest that renal nerves are responsible for marked background stimulation of both renin secretion and renin mRNA expression, which is normally masked by the inhibitory effect of renal perfusion pressure on the renin system. Renal nerve activity is therefore an important determinant of the gain of renin stimulation during reduced renal arterial pressure.
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Affiliation(s)
- C Wagner
- Institut für Physiologie, Universität Regensburg, (Germany).
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Abstract
Renal renin release is affected by several systemic and intrarenal factors. Systemic factors include sympathetic nerves, circulating angiotensin II, blood pressure and salt balance of the organism. Intrarenal factors involved are nitric oxide and the prostaglandins, which stimulate renin secretion.
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Affiliation(s)
- C Wagner
- Department of Physiology, University of Regensburg, Germany
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