1
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Jo SM. Understanding and Treatment Strategies of Hypertension and Hyperkalemia in Chronic Kidney Disease. Electrolyte Blood Press 2023; 21:24-33. [PMID: 37434804 PMCID: PMC10329905 DOI: 10.5049/ebp.2023.21.1.24] [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: 11/17/2022] [Revised: 06/10/2023] [Accepted: 06/12/2023] [Indexed: 07/13/2023] Open
Abstract
Hypertension and potassium imbalance are commonly observed in chronic kidney disease (CKD) patients. The development of hypertension would be related to several mechanisms. Hypertension is related to body mass index, dietary salt intake, and volume overload and is treated with antihypertensives. In CKD patients, managing hypertension can provide important effects that can slow the progression of CKD or reduce complications associated with reduced glomerular filtration rate. The prevalence of hyperkalemia and hypokalemia in CKD patients was similar at 15-20% and 15-18%, respectively, but more attention needs to be paid to treating and preventing hyperkalemia, which is related to a higher mortality rate, than hypokalemia. Hyperkalemia is prevalent in CKD due to impaired potassium excretion. Serum potassium level is affected by renin-angiotensin-aldosterone system inhibitors and diuretics and dietary potassium intake and can be managed by potassium restriction dietary, optimized renin-angiotensin-aldosterone system inhibitor, sodium polystyrene sulfonate, patiromer, and hemodialysis. This review discussed strategies to mitigate and care for the risk of hypertension and hyperkalemia in CKD patients.
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Affiliation(s)
- Sang Min Jo
- Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
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2
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Nanba K, Blinder AR, Rainey WE. Primary Cultures and Cell Lines for In Vitro Modeling of the Human Adrenal Cortex. TOHOKU J EXP MED 2021; 253:217-232. [PMID: 33840647 DOI: 10.1620/tjem.253.217] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The human adrenal cortex is a complex endocrine organ that produces mineralocorticoids, glucocorticoids and androgens. These steroids are produced in distinct cell types located within the glomerulosa, fasciculata and reticularis of the adrenal cortex. Abnormal adrenal steroidogenesis leads to a variety of diseases that can cause hypertension, metabolic syndrome, infertility and premature adrenarche. The adrenal cortex can also develop steroid-producing adenomas and rarely adrenocortical carcinomas. In vitro cell culture models provide important tools to study molecular and cellular mechanisms controlling both the physiologic and pathologic conditions of the adrenal cortex. In addition, the presence of multiple steroid-metabolizing enzymes within adrenal cells makes it a model for defining possible endocrine disruptors that might block these enzymes. The regulation and dysregulation of human adrenal steroid production and cell division/tumor growth can be studied using freshly isolated cells but this requires access to human adrenal glands, which are not available to most investigators. Immortalized human adrenocortical cell lines have proven to be of considerable value in studying the molecular and biochemical mechanisms controlling adrenal steroidogenesis and tumorigenesis. Current human adrenal cell lines include the original NCI-H295 and its substrains: H295A, H295R, HAC13, HAC15, HAC50 and H295RA as well as the recently established MUC-1, CU-ACC1 and CU-ACC2. The current review will discuss the use of primary cultures of fetal and adult adrenal cells as well as adrenocortical cell lines as in vitro models for the study of human adrenal physiology and pathophysiology.
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Affiliation(s)
- Kazutaka Nanba
- Department of Molecular and Integrative Physiology, University of Michigan.,Department of Endocrinology and Metabolism, National Hospital Organization Kyoto Medical Center
| | - Amy R Blinder
- Department of Molecular and Integrative Physiology, University of Michigan
| | - William E Rainey
- Department of Molecular and Integrative Physiology, University of Michigan.,Division of Metabolism, Endocrinology, and Diabetes, Department of Internal Medicine, University of Michigan
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3
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Sapouckey SA, Morselli LL, Deng G, Patil CN, Balapattabi K, Oliveira V, Claflin KE, Gomez J, Pearson NA, Potthoff MJ, Gibson-Corley KN, Sigmund CD, Grobe JL. Exploration of cardiometabolic and developmental significance of angiotensinogen expression by cells expressing the leptin receptor or agouti-related peptide. Am J Physiol Regul Integr Comp Physiol 2020; 318:R855-R869. [PMID: 32186897 DOI: 10.1152/ajpregu.00297.2019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Angiotensin II (ANG II) Agtr1a receptor (AT1A) is expressed in cells of the arcuate nucleus of the hypothalamus that express the leptin receptor (Lepr) and agouti-related peptide (Agrp). Agtr1a expression in these cells is required to stimulate resting energy expenditure in response to leptin and high-fat diets (HFDs), but the mechanism activating AT1A signaling by leptin remains unclear. To probe the role of local paracrine/autocrine ANG II generation and signaling in this mechanism, we bred mice harboring a conditional allele for angiotensinogen (Agt, encoding AGT) with mice expressing Cre-recombinase via the Lepr or Agrp promoters to cause cell-specific deletions of Agt (AgtLepr-KO and AgtAgrp-KO mice, respectively). AgtLepr-KO mice were phenotypically normal, arguing against a paracrine/autocrine AGT signaling mechanism for metabolic control. In contrast, AgtAgrp-KO mice exhibited reduced preweaning survival, and surviving adults exhibited altered renal structure and steroid flux, paralleling previous reports of animals with whole body Agt deficiency or Agt disruption in albumin (Alb)-expressing cells (thought to cause liver-specific disruption). Surprisingly, adult AgtAgrp-KO mice exhibited normal circulating AGT protein and hepatic Agt mRNA expression but reduced Agt mRNA expression in adrenal glands. Reanalysis of RNA-sequencing data sets describing transcriptomes of normal adrenal glands suggests that Agrp and Alb are both expressed in this tissue, and fluorescent reporter gene expression confirms Cre activity in adrenal gland of both Agrp-Cre and Alb-Cre mice. These findings lead to the iconoclastic conclusion that extrahepatic (i.e., adrenal) expression of Agt is critically required for normal renal development and survival.
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Affiliation(s)
- Sarah A Sapouckey
- Department of Neuroscience and Pharmacology, University of Iowa, Iowa City, Iowa
| | - Lisa L Morselli
- Division of Endocrinology, Department of Internal Medicine, University of Iowa, Iowa City, Iowa
| | - Guorui Deng
- Department of Neuroscience and Pharmacology, University of Iowa, Iowa City, Iowa
| | - Chetan N Patil
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | | | - Vanessa Oliveira
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Kristin E Claflin
- Department of Neuroscience and Pharmacology, University of Iowa, Iowa City, Iowa
| | - Javier Gomez
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Nicole A Pearson
- Department of Neuroscience and Pharmacology, University of Iowa, Iowa City, Iowa
| | - Matthew J Potthoff
- Department of Neuroscience and Pharmacology, University of Iowa, Iowa City, Iowa.,Obesity Research & Education Initiative, University of Iowa, Iowa City, Iowa.,Fraternal Order of Eagles' Diabetes Research Center, University of Iowa, Iowa City, Iowa
| | - Katherine N Gibson-Corley
- Fraternal Order of Eagles' Diabetes Research Center, University of Iowa, Iowa City, Iowa.,Department of Pathology, University of Iowa, Iowa City, Iowa
| | - Curt D Sigmund
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin.,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin.,Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Justin L Grobe
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin.,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin.,Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin.,Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, Wisconsin.,Comprehensive Rodent Metabolic Phenotyping Core, Medical College of Wisconsin, Milwaukee, Wisconsin
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4
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Lalli E, Barhanin J, Zennaro MC, Warth R. Local Control of Aldosterone Production and Primary Aldosteronism. Trends Endocrinol Metab 2016; 27:123-131. [PMID: 26803728 DOI: 10.1016/j.tem.2016.01.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 01/08/2016] [Accepted: 01/08/2016] [Indexed: 12/13/2022]
Abstract
Primary aldosteronism (PA) is caused by excessive production of aldosterone by the adrenal cortex and is determined by a benign aldosterone-producing adenoma (APA) in a significant proportion of cases. Local mechanisms, as opposed to circulatory ones, that control aldosterone production in the adrenal cortex are particularly relevant in the physiopathological setting and in the pathogenesis of PA. A breakthrough in our understanding of the pathogenetic mechanisms in APA has been the identification of somatic mutations in genes controlling membrane potential and intracellular calcium concentrations. However, recent data show that the processes of nodule formation and aldosterone hypersecretion can be dissociated in pathological adrenals and suggest a model envisaging different molecular events for the pathogenesis of APA.
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Affiliation(s)
- Enzo Lalli
- Institut de Pharmacologie Moléculaire et Cellulaire CNRS, 06560 Valbonne, France; NEOGENEX CNRS International Associated Laboratory, 06560 Valbonne, France; Université de Nice - Sophia Antipolis, 06560 Sophia Antipolis, France.
| | - Jacques Barhanin
- Laboratoire de PhysioMédecine Moléculaire CNRS-UNS UMR 7370, 06108 Nice Cedex 2, France; Laboratories of Excellence, Ion Channel Science and Therapeutics, 06107 Nice, France
| | - Maria-Christina Zennaro
- INSERM, UMRS 970, Paris Cardiovascular Research Center, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Service de Génétique, 75015 Paris, France
| | - Richard Warth
- Medical Cell Biology - University of Regensburg, 93053 Regensburg, Germany
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5
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Raff H, Gehrand A, Bruder ED, Hoffman MJ, Engeland WC, Moreno C. Renin knockout rat: control of adrenal aldosterone and corticosterone synthesis in vitro and adrenal gene expression. Am J Physiol Regul Integr Comp Physiol 2014; 308:R73-7. [PMID: 25394830 DOI: 10.1152/ajpregu.00440.2014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The classic renin-angiotensin system is partly responsible for controlling aldosterone secretion from the adrenal cortex via the peptide angiotensin II (ANG II). In addition, there is a local adrenocortical renin-angiotensin system that may be involved in the control of aldosterone synthesis in the zona glomerulosa (ZG). To characterize the long-term control of adrenal steroidogenesis, we utilized adrenal glands from renin knockout (KO) rats and compared steroidogenesis in vitro and steroidogenic enzyme expression to wild-type (WT) controls (Dahl S rat). Adrenal capsules (ZG; aldosterone production) and subcapsules [zona reticularis/fasciculata (ZFR); corticosterone production] were separately dispersed and studied in vitro. Plasma renin activity and ANG II concentrations were extremely low in the KO rats. Basal and cAMP-stimulated aldosterone production was significantly reduced in renin KO ZG cells, whereas corticosterone production was not different between WT and KO ZFR cells. As expected, adrenal renin mRNA expression was lower in the renin KO compared with the WT rat. Real-time PCR and immunohistochemical analysis showed a significant decrease in P450aldo (Cyp11b2) mRNA and protein expression in the ZG from the renin KO rat. The reduction in aldosterone synthesis in the ZG of the renin KO adrenal seems to be accounted for by a specific decrease in P450aldo and may be due to the absence of chronic stimulation of the ZG by circulating ANG II or to a reduction in locally released ANG II within the adrenal gland.
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Affiliation(s)
- Hershel Raff
- Endocrine Research Laboratory, Aurora St. Luke's Medical Center, Aurora Research Institute, Milwaukee, Wisconsin; Departments of Medicine, Surgery, and Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin;
| | - Ashley Gehrand
- Endocrine Research Laboratory, Aurora St. Luke's Medical Center, Aurora Research Institute, Milwaukee, Wisconsin
| | - Eric D Bruder
- Endocrine Research Laboratory, Aurora St. Luke's Medical Center, Aurora Research Institute, Milwaukee, Wisconsin
| | - Matthew J Hoffman
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin; and
| | - William C Engeland
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota
| | - Carol Moreno
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin; and
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6
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Bandulik S, Tauber P, Penton D, Schweda F, Tegtmeier I, Sterner C, Lalli E, Lesage F, Hartmann M, Barhanin J, Warth R. Severe hyperaldosteronism in neonatal Task3 potassium channel knockout mice is associated with activation of the intraadrenal renin-angiotensin system. Endocrinology 2013; 154:2712-22. [PMID: 23698720 DOI: 10.1210/en.2013-1101] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Task3 K(+) channels are highly expressed in the adrenal cortex and contribute to the angiotensin II and K(+) sensitivity of aldosterone-producing glomerulosa cells. Adult Task3(-/-) mice display a partially autonomous aldosterone secretion, subclinical hyperaldosteronism, and salt-sensitive hypertension. Here, we investigated the age dependence of the adrenal phenotype of Task3(-/-) mice. Compared with adults, newborn Task3(-/-) mice displayed a severe adrenal phenotype with strongly increased plasma levels of aldosterone, corticosterone, and progesterone. This adrenocortical dysfunction was accompanied by a modified gene expression profile. The most strongly up-regulated gene was the protease renin. Real-time PCR corroborated the strong increase in adrenal renin expression, and immunofluorescence revealed renin-expressing cells in the zona fasciculata. Together with additional factors, activation of the local adrenal renin system is probably causative for the severely disturbed steroid hormone secretion of neonatal Task3(-/-) mice. The changes in gene expression patterns of neonatal Task3(-/-) mice could also be relevant for other forms of hyperaldosteronism.
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Affiliation(s)
- Sascha Bandulik
- Department of Medical Cell Biology, University of Regensburg, 93053 Regensburg, Germany.
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7
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Müller-Fielitz H, Lau M, Jöhren O, Stellmacher F, Schwaninger M, Raasch W. Blood pressure response to angiotensin II is enhanced in obese Zucker rats and is attributed to an aldosterone-dependent mechanism. Br J Pharmacol 2012; 166:2417-29. [PMID: 22452651 DOI: 10.1111/j.1476-5381.2012.01953.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Plasma aldosterone levels correlate positively with obesity, suggesting a link between the hypertension associated with obesity and increased mineralocorticoid levels. We tested the hypothesis that aldosterone is involved in the BP response to angiotensin II (AngII) in obese rats. EXPERIMENTAL APPROACH Lean (LZR) and obese (OZR) Zucker rats were treated with AngII (9 µg·h(-1) ; 4 weeks), and BP and plasma AngII and aldosterone were determined. KEY RESULTS Chronic AngII increased the BP in OZR markedly more so than in LZR. Plasma AngII levels in LZR and OZR were similar after AngII treatment. The AngII stimulated a rise in plasma aldosterone that was sixfold more in OZR than in LZR. The thickness of the zona glomerulosa of the adrenal glands was selectively increased by AngII in OZR. Adrenal mRNA levels of CYP11B2 aldosterone synthase and the AT(1B) receptor were selectively increased in AngII-treated OZR. The BP response to chronic AngII stimulation was diminished in OZR after adrenalectomy when plasma aldosterone was absent. Acute bolus injections of AngII did not increase the BP response or aldosterone release in OZR. CONCLUSIONS AND IMPLICATIONS The AngII-induced BP response is enhanced in obesity and this is associated with a specific increase in circulating aldosterone. Due to the AngII-induced growth of the zona glomerulosa in OZR, the AT(1B) receptors and aldosterone synthase may be selectively enhanced in obesity under concomitant AngII stimulation, increasing the adrenal synthesis of aldosterone. Our results confirm functionally that aldosterone plays a major role in obesity-related hypertension.
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Affiliation(s)
- Helge Müller-Fielitz
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Germany
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8
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Peters J. Local renin-angiotensin systems in the adrenal gland. Peptides 2012; 34:427-32. [PMID: 22391260 DOI: 10.1016/j.peptides.2012.01.023] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Revised: 01/28/2012] [Accepted: 01/28/2012] [Indexed: 10/28/2022]
Abstract
In the adrenal gland all components of the renin-angiotensin system (RAS) are expressed in both the adrenal cortex and the adrenal medulla. In this review evidence shall be presented that a local secretory RAS exists in the adrenal cortex that stimulates aldosterone production and serves as an amplification system for circulating angiotensin (ANG) II. The regulation of the secretory adrenal RAS clearly differs from the regulation of the circulatory RAS in terms of renin expression as well as of renin secretion. For example under potassium load the activity of the renal and circulatory RAS is suppressed whereas the activity of the adrenal RAS is stimulated. Thus the activity of the adrenal RAS but not of the circulating RAS correlates well with the regulation of aldosterone production by potassium. The present review also summarizes the knowledge about the expression and functions of an additional renin transcript that has recently been discovered. This transcript encodes for a non-secretory cytosolic renin isoform. The cytosolic renin may be a basis for the existence of an intracellular renin system in the adrenal gland that has long been proposed. The present state of knowledge shall be discussed indicating that such an intracellular system modulates cell survival and cell death such as apoptosis and necrosis or cell functions such as aldosterone production.
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Affiliation(s)
- Jörg Peters
- Institute of Physiology, University of Greifswald, Germany.
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9
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Abstract
The human adrenal cortex secretes mineralocorticoids, glucocorticoids and adrenal androgens. These steroids are produced from unique cell types located within the three distinct zones of the adrenal cortex. Disruption of adrenal steroid production results in a variety of diseases that can lead to hypertension, metabolic syndrome, infertility and androgen excess. The adrenal cortex is also a common site for the development of adenomas, and rarely the site for the development of carcinomas. The adenomas can lead to diseases associated with adrenal steroid excess, while the carcinomas are particularly aggressive and have a poor prognosis. In vitro cell culture models provide important tools to examine molecular and cellular mechanisms controlling both the normal and pathologic function of the adrenal cortex. Herein, we discuss currently available human adrenocortical carcinoma cell lines and their use as model systems for adrenal studies.
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Affiliation(s)
- Tao Wang
- Department of Physiology, Georgia Health Sciences University, Augusta, GA 30912, USA
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10
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Jansen PM, Hofland J, van den Meiracker AH, de Jong FH, Danser AHJ. Renin and prorenin have no direct effect on aldosterone synthesis in the human adrenocortical cell lines H295R and HAC15. J Renin Angiotensin Aldosterone Syst 2012; 13:360-6. [PMID: 22396488 DOI: 10.1177/1470320312438792] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
INTRODUCTION Transgenic rats expressing the human (pro)renin receptor (h(P)RR) have elevated plasma aldosterone levels despite unaltered levels, in plasma and adrenal, of renin and angiotensin II. MATERIALS AND METHODS To investigate whether renin/prorenin-(P)RR interaction underlies these elevated aldosterone levels, the effect of (pro)renin on steroidogenesis was compared with that of angiotensin II in two (P)RR-expressing human adrenocortical cell lines, H295R and HAC15. Angiotensin II rapidly induced extracellular signal-regulated kinase (ERK) phosphorylation and increased the expression of STAR, CYP21A2, CYP11B2, and CYP17A1 at 6 and 24 hours, whereas the expression of CYP11A1 and HSD3B2 remained unaltered. Incubation with renin or prorenin at nanomolar concentrations had no effect on the expression of any of the steroidogenic enzymes tested, nor resulted in ERK phosphorylation. Angiotensin II, but not renin or prorenin, induced aldosterone production. CONCLUSION Although the (P)RR is present in adrenocortical cells, renin and prorenin do not elicit ERK phosphorylation nor directly affect steroid production via this receptor at nanomolar concentrations. Thus, direct (pro)renin-(P)RR interaction is unlikely to contribute to the elevated aldosterone levels in human (P)RR transgenic rats. This conclusion also implies that the aldosterone rise that often occurs during prolonged renin-angiotensin system blockade is rather due to the angiotensin II 'escape' during such blockade.
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Affiliation(s)
- Pieter M Jansen
- Division of Pharmacology and Vascular Medicine, Department of Internal Medicine, Erasmus Medical Centre Rotterdam, The Netherlands
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11
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Ouyang J, Wu Z, Xing J, Yan Y, Zhang G, Wang B, Li H, Ma X, Zhang X. Association of polymorphisms in angiotensin II receptor genes with aldosterone-producing adenoma. ACTA ACUST UNITED AC 2011; 31:301. [PMID: 21671168 DOI: 10.1007/s11596-011-0371-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Indexed: 11/27/2022]
Abstract
This study examined the association of polymorphisms in angiotensin II receptor genes (AT (1) R and AT (2) R) with the risk for aldosterone-producing adenoma (APA) in a Chinese Han population. Four polymorphisms including rs5182 (573T/C) in exon 4, rs5186 (1166A/C) in 3'-untranslated region (3'-UTR) in AT (1) R gene and rs5194 (2274G/A) in 3'-UTR, rs1403543 (1675G/A) in intron 1 in AT (2) R gene were detected in 148 APA patients and 192 normal subjects (serving as control) by using a MGB-Taqman probe. The distribution of genotypes of each locus was in accordance with Hardy-Weinberg Equilibrium (HWE) in the APA and control groups (P>0.05). The allele A frequency at rs5194 was significantly higher in the APA group (0.49) than in the control group (0.35) (χ (2)=12.08, P=0.001). Subjects with homozygotic genotype AA and heterozygotic genotype GA were at an increased risk for APA as compared to those with GG genotype (OR=2.66, 95% CI=1.45-4.87; OR=1.67, 95% CI=1.02-2.74). Furthermore, rs5194 single-nucleotide polymorphism (SNP) at AT (2) R gene was significantly associated with APA in additive (OR=1.64, 95% CI=1.21-2.20, P=0.001), dominant (OR=1.94, 95% CI=1.23-3.06, P=0.003), and recessive model (OR=2.01, 95% CI=1.17-3.45, P=0.01). It was concluded that rs5194 polymorphism at AT (2) R gene was associated with the risk for APA, which may constitute a genetic marker of APA.
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Affiliation(s)
- Jinzhi Ouyang
- Department of Endocrinology, Chinese PLA General Hospital, Beijing, 100086, China
| | - Zhun Wu
- Department of Urology, the First Affiliated Hospital of Xiamen University, Xiamen, 361003, China
| | - Jinchun Xing
- Department of Urology, the First Affiliated Hospital of Xiamen University, Xiamen, 361003, China
| | - Yongji Yan
- Department of Urology, the Second Affiliated Hospital of Kunming Medical University, Kunming, 650101, China
| | - Guoxi Zhang
- Department of Urology, the First Affiliated Hospital of Gannan Medical University, Ganzhou, 341000, China
| | - Baojun Wang
- Department of Urology, Chinese PLA General Hospital, Beijing, 100086, China
| | - Hongzhao Li
- Department of Urology, Chinese PLA General Hospital, Beijing, 100086, China
| | - Xin Ma
- Department of Urology, Chinese PLA General Hospital, Beijing, 100086, China
| | - Xu Zhang
- Department of Urology, Chinese PLA General Hospital, Beijing, 100086, China.
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12
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Essick EE, Sam F. Cardiac hypertrophy and fibrosis in the metabolic syndrome: a role for aldosterone and the mineralocorticoid receptor. Int J Hypertens 2011; 2011:346985. [PMID: 21747976 PMCID: PMC3124304 DOI: 10.4061/2011/346985] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Accepted: 03/07/2011] [Indexed: 12/28/2022] Open
Abstract
Obesity and hypertension, major risk factors for the metabolic syndrome, render individuals susceptible to an increased risk of cardiovascular complications, such as adverse cardiac remodeling and heart failure. There has been much investigation into the role that an increase in the renin-angiotensin-aldosterone system (RAAS) plays in the pathogenesis of metabolic syndrome and in particular, how aldosterone mediates left ventricular hypertrophy and increased cardiac fibrosis via its interaction with the mineralocorticoid receptor (MR). Here, we review the pertinent findings that link obesity with elevated aldosterone and the development of cardiac hypertrophy and fibrosis associated with the metabolic syndrome. These studies illustrate a complex cross-talk between adipose tissue, the heart, and the adrenal
cortex. Furthermore, we discuss findings from our laboratory that suggest that cardiac hypertrophy and fibrosis in the metabolic syndrome may involve cross-talk between aldosterone and adipokines (such as adiponectin).
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Affiliation(s)
- Eric E Essick
- Whitaker Cardiovascular Institute, Boston University School of Medicine 715 Albany Street, W507 Boston, MA 02118, USA
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13
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Yanes LL, Romero DG. Dihydrotestosterone stimulates aldosterone secretion by H295R human adrenocortical cells. Mol Cell Endocrinol 2009; 303:50-6. [PMID: 19428991 PMCID: PMC2681414 DOI: 10.1016/j.mce.2008.12.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Revised: 12/08/2008] [Accepted: 12/19/2008] [Indexed: 11/22/2022]
Abstract
Men exhibit a higher incidence of cardiovascular diseases than do women. The cardiovascular actions of sex steroids have been suggested as primary factors in mediating this sex difference. The mechanisms by which sex steroids, androgens and estrogens, mediate cardiovascular actions remain unclear. Excess aldosterone secretion has been associated with cardiovascular diseases. The hypothesis tested in this study was that at physiological concentrations, androgens stimulate and estradiol inhibits aldosterone secretion by human adrenal cells. In contrast to our hypothesis, physiological concentrations of sex steroids did not modify aldosterone secretion by H295R human adrenocortical cells. However, supraphysiological concentrations (300-1000 nM) of dihydrotestosterone (DHT) significantly stimulated basal and Angiotensin II-mediated aldosterone secretion. The stimulatory effect of DHT on aldosterone secretion was not blocked by the classical androgen receptor blocker flutamide. The stimulatory effect of DHT on aldosterone secretion was also independent of the intra-adrenal renin-angiotensin system since it was neither modified by treatment with the Angiotensin II receptor type 1 blocker losartan or the angiotensin converting enzyme inhibitor captopril. Inhibitors of the calmodulin/calmodulin-dependent protein kinase (CaMK) and protein kinase C intracellular signaling pathways abolished the DHT stimulatory effect on aldosterone secretion by H295R cells. In conclusion, physiological concentrations of sex steroids did not modify aldosterone secretion by human adrenal cells. However, supraphysiological concentrations of DHT-stimulated aldosterone secretion by human adrenal cells by the calmodulin/CaMK and protein kinase C intracellular signaling pathways but independently of the classical androgen receptor. Supraphysiological doses of androgen may promote cardiovascular diseases via stimulation of aldosterone secretion.
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Affiliation(s)
- Licy L Yanes
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS 39216, USA.
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14
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Pavel J, Benicky J, Murakami Y, Sanchez-Lemus E, Saavedra JM. Peripherally administered angiotensin II AT1 receptor antagonists are anti-stress compounds in vivo. Ann N Y Acad Sci 2009; 1148:360-6. [PMID: 19120129 DOI: 10.1196/annals.1410.006] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Angiotensin II AT(1) receptor blockers (ARBs) are commonly used in the clinical treatment of hypertension. Subcutaneous or oral administration of the ARB candesartan inhibits brain as well as peripheral AT(1) receptors, indicating transport across the blood-brain barrier. Pretreatment with candesartan profoundly modifies the response to stress. The ARB prevents the peripheral and central sympathetic activation characteristic of isolation stress and abolishes the activation of the hypothalamic-pituitary-adrenal axis during isolation. In addition, candesartan prevents the isolation-induced decrease in cortical corticotropin-releasing factor 1 and benzodiazepine receptors induced by isolation. When administered before cold-restraint stress, candesartan totally prevents the production of gastric ulcerations. This preventive effect of candesartan is the consequence of profound anti-inflammatory effects, reduction of sympathetic stimulation, and preservation of blood flow to the gastric mucosa. The ARB does not reduce the hypothalamic-pituitary-adrenal axis stimulation during cold restraint. Preservation of the effects of endogenous glucocorticoids is essential for protection of the gastric mucosa during cold restraint. Administration of the ARB to nonstressed rats decreases anxiety in the elevated plus-maze. Our results demonstrate that Angiotensin II, through AT(1) receptor stimulation, is a major stress hormone, and that ARBs, in addition to their antihypertensive effects, may be considered for the treatment of stress-related disorders.
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Affiliation(s)
- Jaroslav Pavel
- Section on Pharmacology, National Institute of Mental Health, Bethesda, Maryland 20892, USA
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Macova M, Armando I, Zhou J, Baiardi G, Tyurmin D, Larrayoz-Roldan IM, Saavedra JM. Estrogen reduces aldosterone, upregulates adrenal angiotensin II AT2 receptors and normalizes adrenomedullary Fra-2 in ovariectomized rats. Neuroendocrinology 2008; 88:276-86. [PMID: 18679017 PMCID: PMC2677380 DOI: 10.1159/000150977] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Accepted: 04/10/2008] [Indexed: 12/30/2022]
Abstract
We studied the effect of ovariectomy and estrogen replacement on expression of adrenal angiotensin II AT1 and AT2 receptors, aldosterone content, catecholamine synthesis, and the transcription factor Fos-related antigen 2 (Fra-2). Ovariectomy increased AT1 receptor expression in the adrenal zona glomerulosa and medulla, and decreased adrenomedullary catecholamine content and Fra-2 expression when compared to intact female rats. In the zona glomerulosa, estrogen replacement normalized AT1 receptor expression, decreased AT1B receptor mRNA, and increased AT2 receptor expression and mRNA. Estrogen treatment decreased adrenal aldosterone content. In the adrenal medulla, the effects of estrogen replacement were: normalized AT1 receptor expression, increased AT2 receptor expression, AT2 receptor mRNA, and tyrosine hydroxylase mRNA, and normalized Fra-2 expression and catecholamine content. We demonstrate that the constitutive adrenal expression of AT1 receptors, catecholamine synthesis and Fra-2 expression are partially under the control of reproductive hormones. Our results suggest that estrogen treatment decreases aldosterone production through AT1 receptor downregulation and AT2 receptor upregulation. AT2 receptor upregulation and modulation of Fra-2 expression may participate in the estrogen-dependent normalization of adrenomedullary catecholamine synthesis in ovariectomized rats. The AT2 receptor upregulation and the decrease in AT1 receptor function and in the production of the fluid-retentive, pro-inflammatory hormone aldosterone partially explain the protective effects of estrogen therapy.
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Affiliation(s)
- Miroslava Macova
- Section on Pharmacology, Division of Intramural Research Programs, National Institute of Mental Health, National Institutes of Health, Department of Health and Human Services, Bethesda, Md, USA
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16
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Abstract
Angiotensin II (Ang II), the active principle of the renin-angiotensin system (RAS), was discovered as a vasoconstrictive, fluid retentive circulating hormone. It was revealed later that there are local RAS in many organs, including the brain. The physiological receptor for Ang II, the AT(1) receptor type, was found to be highly expressed in many tissues and brain areas involved in the hypothalamic-pituitary-adrenal axis response to stress and in the sympathoadrenal system. The production of circulating and local Ang II, and the expression of AT(1) receptors increase during stress. Blockade of peripheral and brain AT(1) receptors with receptor antagonists administered peripherally prevented the hormonal and sympathoadrenal response to isolation stress, the stress-related alterations in cortical CRF(1) and benzodiazepine receptors, part of the GABA(A) complex, and reduced anxiety in rodents. AT(1) receptor blockade prevented the ulcerations of the gastric mucosa produced by cold-restraint stress, by preservation of the gastric blood flow, prevention of the stress-induced inflammatory response of the gastric mucosa, and partial blockade of the sympathoadrenal response to the stress. Our observations demonstrate that Ang II is an important stress hormone, and that blockade of AT(1) receptors could be proposed as a potentially useful therapy for stress-induced disorders.
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Affiliation(s)
- Juan M Saavedra
- Section on Pharmacology, Department of Health and Human Services, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA.
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17
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Ansurudeen I, Kopprasch S, Ehrhart-Bornstein M, Bornstein SR, Willenberg HS. Endothelial cell-mediated regulation of aldosterone release from human adrenocortical cells. Mol Cell Endocrinol 2007; 265-266:150-6. [PMID: 17257743 DOI: 10.1016/j.mce.2006.12.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Endothelial cells play an important role in the development and functioning of endocrine tissue and endothelial cell-derived factors have been shown to regulate mineralocorticoid release in bovine adrenal cells. In the present study, we analysed the role of human endothelial cells in the synthesis and release of aldosterone from adrenocortical cells (NCI-H295R). Endothelial cell-induced aldosterone release was rapid and lasted as a long-term effect over a period of 48 h. This stimulant effect was influenced by the duration of endothelial cell conditioning and decreased linearly with increasing dilutions of the conditioned medium. At the molecular level, an increase in the mRNA transcripts of aldosterone synthase and StAR could be observed. Cellular interaction with endothelial cell-factors enhanced the activation of CRE, and the promoter activity of both StAR and SF-1 reporter genes. In conclusion, human endothelial cells are important intra-adrenal regulators of human aldosterone synthesis and release.
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Affiliation(s)
- Ishrath Ansurudeen
- Department of Medicine III, Carl Gustav Carus Medical School, University of Technology Dresden, 01307 Dresden, Germany.
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18
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Peters B, Teubner P, Clausmeyer S, Puschner T, Maser-Gluth C, Wrede HJ, Kränzlin B, Peters J. StAR expression and the long-term aldosterone response to high-potassium diet in Wistar-Kyoto and spontaneously hypertensive rats. Am J Physiol Endocrinol Metab 2007; 292:E16-23. [PMID: 16882930 DOI: 10.1152/ajpendo.00454.2005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
ANG II and potassium are known to increase steroidogenic acute regulatory protein (StAR) levels. However, a corresponding increase in StAR mRNA levels has so far been observed only in response to ANG II. We therefore studied the regulation of adrenal StAR mRNA expression in the context of dietary potassium-stimulated aldosterone production. Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) were fed a diet containing either 1 or 4% KCl for 5 days. The high-potassium diet increased StAR mRNA levels within the zona glomerulosa in both strains, as demonstrated by in situ hybridization. However, aldosterone production increased in WKY but not in SHR (WKY: from 22.8 +/- 4.8 to 137 +/- 25 ng/100 ml, P < 0.001, vs. SHR: from 29 +/- 3.8 to 51 +/- 10.2 ng/100 ml, not significant). This increase was associated with an increase in Cyp11b2 mRNA levels in WKY (3-fold; P < 0.001) but not in SHR. In both strains, the 4% KCl diet was associated with increased plasma renin-independent aldosterone production, as indicated by the marked increase of the aldosterone-to-renin ratios (from 1.4 +/- 0.3 to 9 +/- 3 in WKY and from 3 +/- 1 to 14 +/- 5 in SHR; P < 0.002). We conclude that an increase of StAR mRNA levels within the outer cortex is involved in the long-term adrenal response to potassium. This increase alone is not sufficient to increase aldosterone production in the presence of normal Cyp11b2 mRNA levels.
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Affiliation(s)
- Barbara Peters
- Dept. of Physiology, Univ. of Greifswald, Greifswalder Str. 11 C, 17495 Karlsburg, Germany.
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Romero DG, Welsh BL, Gomez-Sanchez EP, Yanes LL, Rilli S, Gomez-Sanchez CE. Angiotensin II-mediated protein kinase D activation stimulates aldosterone and cortisol secretion in H295R human adrenocortical cells. Endocrinology 2006; 147:6046-55. [PMID: 16973724 DOI: 10.1210/en.2006-0794] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Protein kinases are important mediators in intracellular signaling. Angiotensin II is the most important modulator of adrenal zona glomerulosa cell physiology. Angiotensin II regulates steroidogenesis and proliferation among many other metabolic processes. H295R human adrenal cells are a widely used experimental model to study adrenal cell physiology and metabolism. We screened for protein kinase expression levels using the Kinetwork system in H295R cells after 3 h angiotensin II treatment. Protein kinase D (PKD) was the protein kinase that suffers the most dramatic changes. PKD is a member of a new class of serine/threonine protein kinases that is activated by phosphorylation. Our studies indicated that angiotensin II time- and dose-dependently increased PKD phosphorylation, which occurred within 2 min of angiotensin II treatment and at concentrations as low as 1 nm. PKD phosphorylation was also dose-dependently increased by the PKC activator phorbol 12-myristate 13-acetate. Angiotensin II-mediated PKD phosphorylation was blocked by several PKC inhibitors. Furthermore, PKCepsilon translocation inhibitor peptide decreased angiotensin II-mediated PKD phosphorylation, and PKCepsilon down-regulation by RNA interference also decreased PKD phosphorylation mediated by angiotensin II. Cotransfection of constitutively active PKD mutant constructs up-regulated aldosterone synthase and 11beta-hydroxylase expression in reporter assays. Constitutively active PKD mutants increased aldosterone and cortisol secretion under angiotensin II stimulatory conditions. This study reveals that PKD is an intracellular signaling mediator of angiotensin II regulation of steroidogenesis in human adrenal cells. These data provide new insights into the molecular mechanisms involved in angiotensin II-induced physiological and pathophysiological events in adrenal cells.
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Affiliation(s)
- Damian G Romero
- Division of Endocrinology, Department of Medicine, Montgomery Veterans Affairs Medical Center, and The University of Mississippi Medical Center, 2500 North State Street, Jackson, Mississippi 39216, USA.
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20
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Zheng W, Shi M, You SE, Ji H, Roesch DM. Estrogens contribute to a sex difference in plasma potassium concentration: a mechanism for regulation of adrenal angiotensin receptors. ACTA ACUST UNITED AC 2006; 3:43-53. [PMID: 16638600 DOI: 10.1016/s1550-8579(06)80193-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2005] [Indexed: 11/20/2022]
Abstract
BACKGROUND The adrenal mineralocorticoid aldosterone promotes sodium (Na(+)) reabsorption and potassium (K(+)) loss from the kidney. Female sex steroids such as estrogen and progesterone are known modulators of the renin-angiotensin-aldosterone system. OBJECTIVE We conducted studies to determine if there is a sex difference in plasma Na(+) concentration ([Na(+)]) and plasma K(+) concentration ([K(+)]), and if interactions between female sex steroids and aldosterone contribute to a sex difference in these electrolytes. METHODS Plasma [Na(+)] and [K(-)] were determined in weight-matched male and female Sprague-Dawley rats using an ion-selective electrode system. To assess the sensitivity of males and females to aldosterone, the mineralocorticoid was infused chronically by osmotic minipump. The role of female sex steroids in the regulation of plasma electrolyte concentrations was determined in bilaterally ovariectomized (OVX) female rats treated daily with SC injections of progesterone, 17beta-estradiol (E(2)), or selective estrogen receptor (ER) modulators. The role of plasma [K(+)] in the regulation of adrenal angiotensin II type 1 receptor (AT(1)R) expression was determined by manipulating plasma [K(+)] by varying dietary K(-). Adrenal AT(1)R expression was assessed using a radioligand binding assay. RESULTS Plasma [Na(-)] was not different between male and female rats, but plasma [K(-)] was reduced in females compared with males (P = 0.003). In aldosterone-infused female rats, plasma [Na(+)] was increased and plasma [K(+)] was reduced further than in male rats infused with aldosterone (both, P = 0.001). In OVX female rats, progesterone reduced plasma [Na(+)] (P = 0.04) but had no effect on plasma [K(+)]. In contrast, E(2) increased plasma [Na(+)] (P = 0.01) and reduced plasma [K(+)] (P = 0.001). Dietary K supplementation in E(2)-treated rats returned plasma [K(+)] and adrenal AT(1)R binding to levels observed in control rats. Both an ERa and ERP agonist decreased plasma [K(+)] and decreased adrenal AT(1)R binding (both, P < 0.01). CONCLUSIONS In these studies, plasma [K(+)] was reduced in female Sprague-Dawley rats compared with males. The effects of aldosterone on plasma electrolytes were enhanced in females compared with males. E(2) treatment reduced plasma [K(+)] and adrenal AT(1)R binding in OVX rats, and the decrease in plasma [K(+)] contributed to the decrease in adrenal AT(1)R binding. Both ERalpha and ERbeta contributed to the estrogen-induced decrease in plasma [K(+)] and adrenal AT(1)R binding.
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Affiliation(s)
- Wei Zheng
- Division of Nephrology and Hypertension, Georgetown University Medical Center, Washington, DC 20057, USA
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21
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Romero DG, Plonczynski MW, Gomez-Sanchez EP, Yanes LL, Gomez-Sanchez CE. RGS2 is regulated by angiotensin II and functions as a negative feedback of aldosterone production in H295R human adrenocortical cells. Endocrinology 2006; 147:3889-97. [PMID: 16627589 DOI: 10.1210/en.2005-1532] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Regulator of G protein signaling (RGS) proteins interact with Galpha-subunits of heterotrimeric G proteins, accelerating the rate of GTP hydrolysis and finalizing the intracellular signaling triggered by the G protein-coupled receptor-ligand interaction. Angiotensin (Ang) II interacts with its G protein-coupled receptor in zona glomerulosa adrenal cells and triggers a cascade of intracellular signals that regulates steroidogenesis and proliferation. We studied Ang II-mediated regulation of RGS2, the role of RGS2 in steroidogenesis, and the intracellular signal events involved in H295R human adrenal cells. We report that both H295R cells and human adrenal gland express RGS2 mRNA. In H295R cells, Ang II caused a rapid and transient increase in RGS2 mRNA levels quantified by real-time RT-PCR. Ang II effects were mimicked by calcium ionophore A23187 and blocked by calcium channel blocker nifedipine. Ang II effects also were blocked by calmodulin antagonists (W-7 and calmidazolium) and calcium/calmodulin-dependent kinase antagonist KN-93. RGS2 overexpression by retroviral infection in H295R cells caused a decrease in Ang II-stimulated aldosterone secretion but did not modify cortisol secretion. In reporter assays, RGS2 decreased Ang II-mediated aldosterone synthase up-regulation. These results suggest that Ang II up-regulates RGS2 mRNA by the calcium/calmodulin-dependent kinase pathway in H295R cells. RGS2 overexpression specifically decreases aldosterone secretion through a decrease in Ang II-mediated aldosterone synthase-induced expression. In conclusion, RGS2 expression is induced by Ang II to terminate the intracellular signaling cascade generated by Ang II. RGS2 alterations in expression levels or functionality could be implicated in deregulations of Ang II signaling and abnormal aldosterone secretion by the adrenal gland.
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Affiliation(s)
- Damian G Romero
- Division of Endocrinology, Montgomery Veterans Administration Medical Center, USA.
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22
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Seltzer A, Bregonzio C, Armando I, Baiardi G, Saavedra JM. Oral administration of an AT1 receptor antagonist prevents the central effects of angiotensin II in spontaneously hypertensive rats. Brain Res 2005; 1028:9-18. [PMID: 15518636 DOI: 10.1016/j.brainres.2004.06.079] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/30/2004] [Indexed: 11/25/2022]
Abstract
Peripheral and brain angiotensin II AT(1) receptor blockade decreases high blood pressure, stress, and neuronal injury. To clarify the effects of long-term brain Ang II receptor blockade, the AT(1) blocker, candesartan, was orally administered to spontaneously hypertensive rats (SHRs) for 40 days, followed by intraventricular injection of 25 ng of Ang II. Before Ang II injection, AT(1) receptor blockade normalized blood pressure and decreased plasma adrenocorticotropic hormone (ACTH) and corticosterone. After central administration of excess Ang II, the reduction of ACTH and corticosterone release induced by AT(1) receptor blockade no longer occurred. Central Ang II administration to vehicle-treated SHRs further increased blood pressure, provoked drinking, increased tyrosine hydroxylase (TH) mRNA expression in the locus coeruleus, and stimulated sympathoadrenal catecholamine release. Pretreatment with the AT(1) receptor antagonist eliminated Ang II-induced increases in blood pressure, water intake, and sympathoadrenal catecholamine release; inhibited peripheral and brain AT(1) receptors; increased AT(2) receptor binding in the locus coeruleus, inferior olive, and adrenal cortex; and decreased AT(2) receptor binding in the adrenal medulla. Inhibition of brain AT(1) receptors correlated with decreased TH transcription in the locus coeruleus, indicating a decreased central sympathetic drive. This, and the diminished adrenomedullary AT(1) and AT(2) receptor stimulation, result in decreased sympathoadrenomedullary stimulation. Oral administration of AT(1) antagonists can effectively block central actions of Ang II, regulating blood pressure and reaction to stress, and selectively and differentially modulating sympathoadrenal response and the hypothalamic-pituitary-adrenal stimulation produced by brain Ang II--effects of potential therapeutic importance.
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Affiliation(s)
- Alicia Seltzer
- Section on Pharmacology, National Institute of Mental Health, National Institutes of Health, Department of Health and Human Services, Bldg 10, Rm 2D57, 10 Center Dr, MSC-1514, Bethesda, MD 20892, USA
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23
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Abstract
The human adrenal cortex is a complex endocrine organ that secretes mineralocorticoids, glucocorticoids and adrenal androgens. These steroids arise from morphologically and biochemically distinct zones of the adrenal gland. Studying secretion of these distinct steroid hormones can make use of cells isolated from the adrenal gland but this requires animal sacrifice and the need for continued isolation for long-term studies. In addition primary cultures of adrenal cells have a limited life-span in culture and the cultured cells are often contaminated by the presence of non-steroidogenic cells. For that reason in vitro cell culture models have several benefits for research on adrenocortical function. Herein we discuss the available adrenocortical cell lines and their uses as model systems for adrenal studies. Focus is placed on the human NCI-H295 and mouse Y-1 adrenal cell lines, which have been used extensively as adrenocortical model systems. These cell lines have proven to be of considerable value in studying the molecular and biochemical mechanisms controlling adrenal steroidogenesis. The current review will discuss the attributes and limitations of the currently available adrenocortical cell lines as models for adrenal studies.
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Affiliation(s)
- William E Rainey
- Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9032, USA.
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Tan LB, Schlosshan D, Barker D. Fiftieth anniversary of aldosterone: from discovery to cardiovascular therapy. Int J Cardiol 2004; 96:321-33. [PMID: 15310530 DOI: 10.1016/j.ijcard.2004.05.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2004] [Accepted: 05/02/2004] [Indexed: 11/19/2022]
Abstract
Half a century after the elucidation of its molecular structure, aldosterone is generating the greatest interest, not in the fields of endocrinology or renal medicine but in cardiology-where aldosterone over-activation is now perceived as detrimental in heart failure (HF) and ischaemic heart disease. Clinically, excess aldosterone is associated with higher morbidity and mortality after myocardial infarction (MI) and HF. The Randomised Aldactone Evaluation Study (RALES) study in severe chronic heart failure and the Eplerenone Post-Acute Myocardial Infarction Heart Failure Efficacy and Survival (EPHESUS) study in post-MI heart failure have shown that use of non-selective and selective aldosterone receptor antagonists, respectively, improves prognosis. The pathophysiological mechanisms underpinning these damaging aldosterone-mediated cardiovascular effects are still being elucidated, but prime candidates include cardiomyocyte necrosis and apoptosis, and myocardial fibrosis resulting in adverse cardiac remodelling, coronary vasculopathy, tachyarrhythmia and positive feedback activation of the renin-angiotensin-aldosterone system. Practical points for consideration when instigating therapy include preferential use of aldosterone receptor antagonists to maintain electrolyte balance whenever loop or thiazide diuretics are used (vulnerable HF patients require higher ranges of potassium and magnesium to minimise propensity for tachyarrthythmia), for renoprotection and for counteracting aldosterone breakthrough despite adequate ACE inhibition; use of the minimum doses of loop diuretics required to lessen activation of the renin-angiotensin-aldosterone system in HF; use of selective aldosterone receptor antagonists to avoid gynaecomastia/mastalgia and impotence; and prophylactic use of aldosterone receptor antagonists to improve prognosis.
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Affiliation(s)
- Lip-Bun Tan
- Academic Unit of Molecular Cardiovascular Medicine, University of Leeds, G Floor, Martin Wing, Leeds General Infirmary, Leeds, LS1 3EX, UK
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25
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Ehrhart-Bornstein M, Lamounier-Zepter V, Schraven A, Langenbach J, Willenberg HS, Barthel A, Hauner H, McCann SM, Scherbaum WA, Bornstein SR. Human adipocytes secrete mineralocorticoid-releasing factors. Proc Natl Acad Sci U S A 2003; 100:14211-6. [PMID: 14614137 PMCID: PMC283571 DOI: 10.1073/pnas.2336140100] [Citation(s) in RCA: 316] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Obesity has become an epidemic problem in western societies, contributing to metabolic diseases, hypertension, and cardiovascular disease. Overweight and obesity are frequently associated with increased plasma levels of aldosterone. Recent evidence suggests that human fat is a highly active endocrine tissue. Therefore, we tested the hypothesis that adipocyte secretory products directly stimulate adrenocortical aldosterone secretion. Secretory products from isolated human adipocytes strongly stimulated steroidogenesis in human adrenocortical cells (NCI-H295R) with a predominant effect on mineralocorticoid secretion. Aldosterone secretion increased 7-fold during 24 h of incubation. This stimulation was comparable to maximal stimulation of these cells with forskolin (2 x 10(-5) M). On the molecular level, there was a 10-fold increase in the expression of steroid acute regulatory peptide mRNA. This effect was independent of adipose angiotensin II as revealed by the stimulatory effect of fat cell-conditioned medium even in the presence of the angiotensin type 1 receptor antagonist, valsartan. None of the recently defined adipocytokines accounted for the effect. Mineralocorticoid-stimulating activity was heat sensitive and could be blunted by heating fat cell-conditioned medium to 99 degrees C. Centrifugal filtration based on molecular mass revealed at least two releasing factors: a heat sensitive fraction (molecular mass >50 kDa) representing 60% of total activity, and an inactive fraction (molecular mass <50 kDa). However, the recovery rate increased to 92% when combining these two fractions, indicating the interaction of at least two factors. In conclusion, human adipocytes secrete potent mineralocorticoid-releasing factors, suggesting a direct link between obesity and hypertension.
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26
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Vrezas I, Willenberg HS, Mansmann G, Hiroi N, Fritzen R, Bornstein SR. Ectopic adrenocorticotropin (ACTH) and corticotropin-releasing hormone (CRH) production in the adrenal gland: basic and clinical aspects. Microsc Res Tech 2003; 61:308-14. [PMID: 12768546 DOI: 10.1002/jemt.10340] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The hypothalamic-pituitary-adrenal (HPA) axis is integrated in the human stress system and controls the metabolism of many cell systems in the body. Therefore, hypofunction or hyperfunction of the HPA axis potentially threatens the life of the whole organism. Noncontrolled overproduction of its key regulators, CRH and ACTH, causes dysfunction of the stress system. Ectopic secretion of these compounds may be part of extraadrenal paraneoplastic syndromes caused by various benign or malignant tumors. However, ectopic ACTH and CRH may originate from the adrenal itself. A local CRH/ACTH system exists in the normal human adrenal medulla. Overproduction of CRH and ACTH has been documented in pheochromocytomas causing Cushing's syndrome. Finally, ectopic production of ACTH causing Cushing's syndrome has also been demonstrated in adrenocortical cells. This suggests a marked plasticity within the HPA axis and the neuroendocrine cell system.
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Affiliation(s)
- Ilias Vrezas
- Department of Endocrinology, University Hospital of Duesseldorf, 40225 Duesseldorf, Germany.
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27
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Betancourt-Calle S, Jung EM, White S, Ray S, Zheng X, Calle RA, Bollag WB. Elevated K(+) induces myristoylated alanine-rich C-kinase substrate phosphorylation and phospholipase D activation in glomerulosa cells. Mol Cell Endocrinol 2001; 184:65-76. [PMID: 11694342 DOI: 10.1016/s0303-7207(01)00642-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Elevated extracellular potassium concentrations ([K(+)](e)) are known to stimulate aldosterone secretion from adrenal glomerulosa cells in vivo and in vitro. The mechanism is thought to involve depolarization-elicited activation of voltage-dependent calcium channels and an increase in calcium influx. Until now protein kinase C (PKC) was thought not to play a role in the steroidogenic response to elevated [K(+)](e). In this report, we provide evidence in bovine adrenal glomerulosa cells to suggest that elevated [K(+)](e) increases PKC activity, as shown by an enhancement in the phosphorylation of myristoylated alanine-rich C-kinase substrate (MARCKS). Elevated [K(+)](e)-induced MARCKS phosphorylation was delayed and transient and was not the result of a local production of angiotensin II (AngII). MARCKS phosphorylation in response to elevated [K(+)](e) was not accompanied by phosphoinositide hydrolysis but was inhibited by a selective PKC inhibitor. Elevated [K(+)](e) also activated phospholipase D (PLD) in a delayed but sustained manner. We propose that the observed PLD activation mediates the elevated [K(+)](e)-induced MARCKS phosphorylation via PKC, although other factors may modulate this phosphorylation event.
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Affiliation(s)
- S Betancourt-Calle
- Program in Cell Signaling, Department of Medicine, Institute of Molecular Medicine and Genetics, Medical College of Georgia, 1120 15th Street, Augusta, GA 30912-2630, USA
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28
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Dechow C, Morath C, Peters J, Lehrke I, Waldherr R, Haxsen V, Ritz E, Wagner J. Effects of all-trans retinoic acid on renin-angiotensin system in rats with experimental nephritis. Am J Physiol Renal Physiol 2001; 281:F909-19. [PMID: 11592949 DOI: 10.1152/ajprenal.2001.281.5.f909] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
We previously demonstrated that all-trans retinoic acid (RA) preserves glomerular structure and function in anti-Thy1.1 nephritis (Wagner J, Dechow C, Morath C, Lehrke I, Amann K, Floege J, and Ritz E. J Am Soc Nephrol 11: 1479-1489, 2000). Because the renin-angiotensin system (RAS) contributes to renal damage, we 1) studied retinoid-specific effects on its components and 2) compared the effects of all-trans-RA with those of the AT(1)-receptor blocker candesartan. Rats were pretreated for 3 days before injection of the OX-7 antibody and continued with treatment with either vehicle or daily injections of 10 mg/kg all-trans-RA only (study 1) or 10 mg/kg body wt all-trans-RA, 1 mg/kg candesartan, or both (study 2) for an additional 7 days. The blood pressure increase observed in anti-Thy1.1 nephritic rats was equally normalized by all-trans-RA and candesartan (P < 0.05). In nephritic rats, mRNAs of angiotensinogen and angiotensin-converting enzyme (ACE) in the kidney were unchanged, but renin mRNA was lower (P < 0.01). Renal and glomerular AT(1)-receptor gene and protein expression levels were higher in anti-Thy1.1 nephritic rats (P < 0.05). In the renal cortex of nephritic rats, pretreatment with all-trans-RA significantly reduced mRNAs of all the examined RAS components, but in the glomeruli it increased ACE gene and protein expression (P < 0.01). In nephritic rats, candesartan reduced the number of glomerular cells and mitoses (P < 0.05) less efficiently than all-trans-RA (P < 0.01). Both substances reduced cellular proliferation (proliferating cell nuclear antigen) significantly (P < 0.05). No additive effects were noted when both compounds were combined. In conclusion, all-trans-RA influences the renal RAS in anti-Thy1.1 nephritis by decreasing ANG II synthesis and receptor expression. The beneficial effect of retinoids may be explained, at least in part, by reduction of RAS activity.
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Affiliation(s)
- C Dechow
- Division of Nephrology, University of Heidelberg, D-69115, Germany
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Saavedra JM, Armando I, Terrón JA, Falcón-Neri A, Jöhren O, Häuser W, Inagami T. Increased AT(1) receptors in adrenal gland of AT(2) receptor gene-disrupted mice. REGULATORY PEPTIDES 2001; 102:41-7. [PMID: 11600209 DOI: 10.1016/s0167-0115(01)00303-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Angiotensin II (Ang II) AT(2) receptor-gene disrupted mice have increased systemic blood pressure and response to exogenous Angiotensin II. To clarify the mechanism of these changes, we studied adrenal AT(1) receptor expression and mRNA by receptor autoradiography and in situ hybridization in female AT(2) receptor-gene disrupted mice (agtr 2-/-) and wild-type controls (agtr 2+/+). We found high expression of AT(1) receptor binding and mRNA in adrenal zona glomerulosa of female wild-type mice. AT(2) receptors and mRNA were highly expressed in adrenal medulla of wild-type mice, but were not detected in zona glomerulosa. There was no AT(2) receptor binding or mRNA in adrenal glands of AT(2) receptor-gene disrupted mice. In these animals, AT(1) receptor binding and mRNA were increased in adrenal zona glomerulosa and AT(1) receptor mRNA was increased in the adrenal medulla when compared with wild-type animals.The present data support the hypothesis of an interaction or cross talk between AT(2) and AT(1) receptors in adrenal gland. The significant increase in AT(1) receptor expression in the absence of AT(2) receptor transcription may be partially responsible for the increased blood pressure and for the enhanced response to exogenously administered Angiotensin II in this model.
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MESH Headings
- Adrenal Medulla/metabolism
- Angiotensin II/pharmacology
- Animals
- Autoradiography
- Blood Pressure/drug effects
- Female
- Gene Expression Regulation
- Genotype
- Imidazoles/pharmacology
- In Situ Hybridization
- Losartan/pharmacology
- Mice
- Mice, Inbred Strains
- Mice, Knockout
- Mice, Mutant Strains
- Pyridines/pharmacology
- RNA, Messenger/metabolism
- Receptor, Angiotensin, Type 1
- Receptor, Angiotensin, Type 2
- Receptors, Angiotensin/deficiency
- Receptors, Angiotensin/genetics
- Receptors, Angiotensin/metabolism
- Transcription, Genetic
- Vasoconstrictor Agents/pharmacology
- Zona Glomerulosa/drug effects
- Zona Glomerulosa/metabolism
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Affiliation(s)
- J M Saavedra
- Section on Pharmacology, National Institute of Mental Health, 10 Center Drive MSC 1514, Building 10, Room 2D-57, Bethesda, MD 20892, USA.
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Kantachuvesiri S, Fleming S, Peters J, Peters B, Brooker G, Lammie AG, McGrath I, Kotelevtsev Y, Mullins JJ. Controlled hypertension, a transgenic toggle switch reveals differential mechanisms underlying vascular disease. J Biol Chem 2001; 276:36727-33. [PMID: 11448960 DOI: 10.1074/jbc.m103296200] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A novel inbred rat model with inducible hypertension has been generated using a renin transgene under the transcriptional control of the cytochrome P450, Cyp1a1 promoter. The degree and duration of hypertension are regulated tightly by administration of the natural xenobiotic indole-3 carbinol and can be readily reversed. Induction experiments reveal distinct temporal and mechanistic responses to hypertensive injury in different vascular beds, which is indicative of differential susceptibility of organs to a hypertensive stimulus. The mesentery and heart exhibited the greatest sensitivity to damage, and the kidney showed an adaptive response prior to the development of malignant hypertensive injury. Quantitative analysis of morphological changes induced in mesenteric resistance arteries suggest eutrophic remodeling of the vessels. Kinetic evidence suggests that locally activated plasma prorenin may play a critical role in mediating vascular injury. This model will facilitate studies of the cellular and genetic mechanisms underlying vascular injury and repair and provide a basis for the identification of novel therapeutic targets for vascular disease.
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Affiliation(s)
- S Kantachuvesiri
- Molecular Physiology Laboratory, University of Edinburgh Medical School, Wilkie Building, Teviot Place, Edinburgh EH8 9AG, United Kingdom
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31
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Stokes GS, Monaghan JC, Ryan M, Woodward M. Efficacy of an angiotensin II receptor antagonist in managing hyperaldosteronism. J Hypertens 2001; 19:1161-5. [PMID: 11403366 DOI: 10.1097/00004872-200106000-00022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To determine whether an angiotensin II receptor antagonist decreases blood pressure in patients with hyperaldosteronism and hypertension who are taking other antihypertensive agents. DESIGN A double-blind randomized placebo-controlled crossover study. PATIENTS AND METHODS Blood pressure and hormonal responses to 2-week courses of placebo/irbesartan (150 mg/day given by mouth at 08.05 h) were assessed in 10 patients with hyperaldosteronism. Clinic blood pressure was measured by sphygmomanometer, and plasma concentrations of aldosterone, cortisol, angiotensin II, electrolytes and renin activity (PRA) were determined weekly. Automated 24 h ambulatory blood pressure recordings were made at the end of the active and placebo phases. RESULTS Irbesartan caused a post-dose decrease in ambulatory blood pressure (systolic, P = 0.02; diastolic, P = 0.05) in the period from 10.00 h to 20.00 h. Clinic blood pressure, measured at trough, was not significantly decreased. Plasma aldosterone decreased (P < 0.03) and PRA increased (P < 0.04) in the first week of active treatment with irbesartan, but differences between the placebo and active-treatment groups were not significant in the second week. There were no significant changes in plasma concentrations of angiotensin II, cortisol or potassium in either week. In the second week of irbesartan treatment, there were associations between change in plasma aldosterone and maximal change in ambulatory blood pressure (systolic and diastolic). CONCLUSION Irbesartan has a role in combination antihypertensive treatment of patients with hyperaldosteronism.
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Affiliation(s)
- G S Stokes
- Department of Cardiology, Royal North Shore Hospital, St Leonards, NSW, Australia.
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Daido H, Zhou MY, Gomez-Sanchez CE. Angiotensin stimulates the expression of interferon-inducible genes in H295R cells. Mol Cell Endocrinol 2001; 176:21-7. [PMID: 11369439 DOI: 10.1016/s0303-7207(01)00478-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Angiotensin-II (A-II) induces proliferation of zona glomerulosa cells and stimulates expression of cytochrome P-450 aldosterone synthase. The genes activated during this adrenal remodeling are not well defined. To clarify this mechanism, we sought to identify the genes whose expression is stimulated by A-II in the H295R cell line. Using a subtractive hybridization technique, we identified one clone whose expression was stimulated by A-II. The sequence of this gene was homologous to the human interferon-inducible genes, 9-27, 1-8D and 1-8U. The 5' portion of the gene was identical to the 1-8D gene product and the 3' was identical to the 9-27 gene product, but the existence of a transcript was not demonstrated by RT-PCR. The expression of these three genes was stimulated by A-II, with the 9-27 gene being most abundant. Potassium and forskolin also stimulated the expression of the 9-27 gene in the H295R cells, but not as effectively as did A-II or interferon-gamma.
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Affiliation(s)
- H Daido
- Division of Endocrinology, University of Missouri, Columbia, MO 65212, USA
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Mazzocchi G, Malendowicz LK, Markowska A, Albertin G, Nussdorfer GG. Role of adrenal renin-angiotensin system in the control of aldosterone secretion in sodium-restricted rats. Am J Physiol Endocrinol Metab 2000; 278:E1027-30. [PMID: 10827004 DOI: 10.1152/ajpendo.2000.278.6.e1027] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study examined the effect of the pharmacological manipulation of adrenal renin-angiotensin system (RAS) on aldosterone secretion from in situ perfused adrenals of rats kept on a normal diet and sodium restricted for 14 days. Neither the angiotensin-converting enzyme inhibitor captopril nor the nonselective angiotensin II receptor antagonist saralasin and the AT(1) receptor-selective antagonist losartan affected basal aldosterone output in normally fed rats. In contrast, they concentration dependently decreased aldosterone secretion in sodium-restricted animals, with maximal effective concentration ranging from 10(-7) to 10(-6) M. Captopril (10(-6) M), saralasin (10(-6) M), and losartan (10(-7) M) counteracted aldosterone response to 10 mM K(+) in sodium-restricted rats but not in normally fed animals. Collectively, these findings provide evidence that adrenal RAS plays a role in the regulation of aldosterone secretion, but only under conditions of prolonged stimulation of zona glomerulosa probably leading to overexpression of adrenal RAS.
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Affiliation(s)
- G Mazzocchi
- Section of Anatomy, Department of Human Anatomy and Physiology, University of Padua, I-35121 Padua, Italy
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