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Sample records for angiotensin aldosterone system

  1. Effect of Dual Blockade of Renin-Angiotensin Aldosterone System ...

    African Journals Online (AJOL)

    Original Research Article. Effect of Dual Blockade of Renin-Angiotensin Aldosterone. System on Proteinuria in Patients with Diabetic. Nephropathy and Advanced Azotemia. Hatice Odabas1, İlyas Capoglu2, Ramazan Cetinkaya3, Ali Riza Odabas3,. Abdullah Uyanik3 and Mustafa Keles3*. 1Department of Internal Medicine, ...

  2. Molecular Mechanisms Underlying Renin-Angiotensin-Aldosterone System Mediated Regulation of BK Channels

    OpenAIRE

    Zhang, Zhen-Ye; Qian, Ling-Ling; Wang, Ru-Xing

    2017-01-01

    Large-conductance calcium-activated potassium channels (BK channels) belong to a family of Ca2+-sensitive voltage-dependent potassium channels and play a vital role in various physiological activities in the human body. The renin-angiotensin-aldosterone system is acknowledged as being vital in the body's hormone system and plays a fundamental role in the maintenance of water and electrolyte balance and blood pressure regulation. There is growing evidence that the renin-angiotensin-aldosterone...

  3. MATHEMATICAL MODEL FOR THE RENIN-ANGIOTENSIN-ALDOSTERONE SYSTEM IN PATIENTS

    OpenAIRE

    Dr. T. Geetha; K. Balamurugan

    2016-01-01

    In this paper we use mathematical model for the application of The Renin-Angiotensin-Aldosterone system the difference of sleep related activity of the RAAS between depressed patients and healthy controls. We studied the nocturnal plasma concentration of ACTH, cortisol, renin and aldosterone, and sleep EEG in 7 medication free patients with depression. The huge increase in aldosterone in depressed subjects compared to controls and the unchanged cross correlation between the time course of noc...

  4. Molecular Mechanisms Underlying Renin-Angiotensin-Aldosterone System Mediated Regulation of BK Channels

    Directory of Open Access Journals (Sweden)

    Zhen-Ye Zhang

    2017-09-01

    Full Text Available Large-conductance calcium-activated potassium channels (BK channels belong to a family of Ca2+-sensitive voltage-dependent potassium channels and play a vital role in various physiological activities in the human body. The renin-angiotensin-aldosterone system is acknowledged as being vital in the body's hormone system and plays a fundamental role in the maintenance of water and electrolyte balance and blood pressure regulation. There is growing evidence that the renin-angiotensin-aldosterone system has profound influences on the expression and bioactivity of BK channels. In this review, we focus on the molecular mechanisms underlying the regulation of BK channels mediated by the renin-angiotensin-aldosterone system and its potential as a target for clinical drugs.

  5. [Elevated serum aldosterone levels in dialysis patients: Are we underusing renin-angiotensin-aldosterone system blockers?

    Science.gov (United States)

    Fernández-Reyes, M J; Velasco, S; Gutierrez, C; Gonzalez Villalba, M J; Heras, M; Molina, A; Callejas, R; Rodríguez, A; Calle, L; Lopes, V

    Serum aldosteronelevels (SA) are a marker of cardiovascular (CV) risk in the general population. To analyze SA levels in dialysis patients and its relationship with characteristics of dialysis; comorbidity; blood pressure and the use of blocking renin-angiotensin-aldosterone system agents (BSRAA). We determined SA in 102 patients: 81 on hemodialysis (HD) and 21 on peritoneal dialysis. Mean age 71.4±12 years; 54.9% male; 29.4% diabetics. Mean time on dialysis 59.3±67 months. In 44 HD patients plasma renin activity (PRA) was measured. Mean SA was 72.6±114.9ng/dl (normal range 1.17-23.6ng/dl). A total of 57.8% of patients had above normal levels which were not related to dialysis characteristics or comorbidity. Only 21% of patients with heart failure and 19.2% with ischemic heart disease used BSRAA. A number of 25 patients treated with BSRAA had significantly lower levels of SA. There was an inverse correlation between AS and systolic blood pressure (SBP), and direct with PRA. The logistic regression analysis conducted to find SA levels above the median associated factors showed that SBP was the only independent risk variable in the overall population (OR 0.97; P=.022); in the 44 patients in whom PRA was determined this was the only independent risk factor (OR 2.24; P=.012). A high percentage of dialysis patients have elevated levels of SA that are associated to diminished SBP and activated PRA and not to dialysis characteristics. In patients with a history of heart disease we underuse BSRAA. Copyright © 2016 SEH-LELHA. Publicado por Elsevier España, S.L.U. All rights reserved.

  6. Dual Blockade of the Renin-angiotensin-aldosterone System in Type 2 Diabetic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Yan-Huan Feng

    2016-01-01

    Full Text Available Objective: To examine the efficacy and safety of dual blockade of the renin-angiotensin-aldosterone system (RAAS among patients with type 2 diabetic kidney disease. Data Sources: We searched the major literature repositories, including the Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE, for randomized clinical trials published between January 1990 and October 2015 that compared the efficacy and safety of the use of dual blockade of the RAAS versus the use of monotherapy, without applying any language restrictions. Keywords for the searches included "diabetic nephropathy," "chronic kidney disease," "chronic renal insufficiency," "diabetes mellitus," "dual therapy," "combined therapy," "dual blockade," "renin-angiotensin system," "angiotensin-converting enzyme inhibitor," "angiotensin-receptor blocker," "aldosterone blockade," "selective aldosterone blockade," "renin inhibitor," "direct renin inhibitor," "mineralocorticoid receptor blocker," etc. Study Selection: The selected articles were carefully reviewed. We excluded randomized clinical trials in which the kidney damage of patients was related to diseases other than diabetes mellitus. Results: Combination treatment with an angiotensin-converting enzyme inhibitor supplemented by an angiotensin II receptor blocking agent is expected to provide a more complete blockade of the RAAS and a better control of hypertension. However, existing literature has presented mixed results, in particular, related to patient safety. In view of this, we conducted a comprehensive literature review in order to explain the rationale for dual blockade of the RAAS, and to discuss the pros and cons. Conclusions: Despite the negative results of some recent large-scale studies, it may be immature to declare that the dual blockade is a failure because of the complex nature of the RAAS surrounding its diversified functions and utility. Further trials are warranted to study the combination therapy as an

  7. Renin-angiotensin-aldosterone system inhibition: overview of the therapeutic use of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, mineralocorticoid receptor antagonists, and direct renin inhibitors.

    Science.gov (United States)

    Mercier, Kelly; Smith, Holly; Biederman, Jason

    2014-12-01

    Angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) therapy in hypertensive diabetic patients with macroalbuminuria, microalbuminuria, or normoalbuminuria has been repeatedly shown to improve cardiovascular mortality and reduce the decline in glomerular filtration rate. Renin-angiotensin-aldosterone system (RAAS) blockade in normotensive diabetic patients with normoalbuminuria or microalbuminuria cannot be advocated at present. Dual RAAS inhibition with ACE inhibitors plus ARBs or ACE inhibitors plus direct renin inhibitors has failed to improve cardiovascular or renal outcomes but has predisposed patients to serious adverse events. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Effect of Dual Blockade of Renin-Angiotensin Aldosterone System ...

    African Journals Online (AJOL)

    Purpose: To investigate the dual effect of angiotensin blockade by irbesartan and enalapril on proteinuria in diabetic patients with azotemia. Methods: Patients with diabetes of > 5 years duration, proteinuria at a nephrotic level and serum creatinine > 1.5 mg/dL were enrolled in the study. Forty-five enrolled patients were ...

  9. Renin-angiotensin-aldosterone system in bodybuilders using supraphysiological doses of anabolic-androgenic steroids

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    K Chrostowski

    2011-03-01

    Full Text Available This study was carried out in 40 bodybuilders voluntarily taking supraphysiological doses of anabolic-androgenic steroids (AAS. Echocardiographic examination of the heart and blood analysis were performed, and concentration of AAS in urine was examined. The presence, or absence, of AAS in urine had no influence on the echocardiographic parameters of the heart, body mass, body mass index (BMI and aldosterone level in blood plasma. It seems, therefore, that the presence of AAS in urine may confirm heart hypertrophy and overuse of AAS, while the absence of AAS in urine does not exclude the cardiological changes occurring as a result of taking the drugs. Metabolites detected in urine showed that the intake of 17α-alkyl testosterone derivatives caused higher values of left ventricular mass and BMI. However, the level of HDL cholesterol was lower in bodybuilders using only 19-nor-testosterone. Elevated level of plasma aldosterone did not differ between the two groups. As could be expected, the highest level of AAS in urine was detected in bodybuilders currently self-administering the anabolic-androgenic steroids (on cycle. The level of AAS in the urine decreased after stopping taking the drugs (off cycle. Refraining from AAS abuse for a period of 1-2 years was associated with a significant decrease in aldosterone level in the plasma. The positive correlations found between the blood plasma aldosterone, left ventricular mass and BMI lead to the conclusion that large doses of AAS taken by bodybuilders would cause extra activation of the renin-angiotensin-aldosterone system.

  10. Radioimmunologic analysis of the state of the renin-angiotensin-aldosterone system in arterial hypertension

    International Nuclear Information System (INIS)

    Slavnov, V.N.; Yakovlev, A.A.; Gandzha, T.I.; Yugrinov, O.G.

    1986-01-01

    For 110 patients having various forms of arterial hypertension (hypertension, aldersteronoma, phaeochromocytoma, corticosteroma) the parameters of the system renin-angiotensin-aldosterone (RAA) were measured. Basal values of aldosterone and renin activity in blood were determined as well as their concentration in blood taken from the vena cava inferior, renal and adrenal veins during selective renography. The 24-hours rhythm of the hormones in the blood, the reaction of the glomerular zone of the adrenal cortex and the juxtaglomerular renal system under acute lasix stress was evaluated. It was found, that the system RAA is disturbed in all patients with arterial hypertension. This is indicated by changes of aldosterone concentration, renin activity in peripheral blood and in the blood from the vena cava inferior, renal and adrenal veins, the 24-hour rhythm of their concentrations in serum and the reaction to acute lasix stress. The radioimmunoassays of quantitative parameters of the RAA system are decisive for the differential diagnostics of hypertension and suprarenomas connected with a hypertension syndrome. They facilitate a rational choice of the hypertension therapy and the daily distribution of the medicaments for patients with hypertension. The radioimmunoassays can be used for checking the efficiency of medicaments and surgery. (author)

  11. Independent regulation of renin-angiotensin-aldosterone system in the kidney.

    Science.gov (United States)

    Nishiyama, Akira; Kobori, Hiroyuki

    2018-03-29

    Renin-angiotensin-aldosterone system (RAAS) plays important roles in regulating renal hemodynamics and functions, as well as in the pathophysiology of hypertension and renal disease. In the kidney, angiotensin II (Ang II) production is controlled by independent multiple mechanisms. Ang II is compartmentalized in the renal interstitial fluid with much higher concentrations than those existing in the circulation. Inappropriate activation of the intrarenal RAAS is an important contributor to the pathogenesis of hypertension and renal injury. It has been revealed that intrarenal Ang II levels are predominantly regulated by angiotensinogen and therefore, urinary angiotensinogen could be a biomarker for intrarenal Ang II generation. In addition, recent studies have demonstrated that aldosterone contributes to the progression of renal injury via direct actions on glomerular podocytes, mesangial cells, proximal tubular cells and tubulo-interstitial fibroblasts through the activation of locally expressed mineralocorticoid receptor. Thus, it now appears that intrarenal RAAS is independently regulated and its inappropriate activation contributes to the pathogenesis of the development of hypertension and renal disease. This short review article will focus on the independent regulation of the intrarenal RAAS with an emphasis on the specific role of angiotensinogen.

  12. Gene-load score of the renin-angiotensin-aldosterone system is associated with coronary heart disease in familial hypercholesterolaemia

    NARCIS (Netherlands)

    van der Net, Jeroen B.; van Etten, Jeroen; Yazdanpanah, Mojgan; Dallinga-Thie, Geesje M.; Kastelein, John J. P.; Defesche, Joep C.; Koopmans, Richard P.; Steyerberg, Ewout W.; Sijbrands, Eric J. G.

    2008-01-01

    AIMS: Familial hypercholesterolaemia (FH) is characterized by premature coronary heart disease (CHD). However, the incidence of CHD varies considerably among FH patients. Genetic variation in the renin-angiotensin-aldosterone system (RAAS) and the adrenalin/noradrenalin system may be of importance

  13. The role of the renin-angiotensin-aldosterone system in heart failure

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    Thomas Unger

    2004-03-01

    Full Text Available Activity of the renin-angiotensin-aldosterone system (RAAS is increased in patients with heart failure, and its maladaptive mechanisms may lead to adverse effects such as cardiac remodelling and sympathetic activation. Elevated renin activity has been demonstrated in patients with dilated cardiomyopathy. (Third-generation synthetic non-peptide renin inhibitors, with more favourable properties than earlier renin inhibitors, lower ambulatory blood pressure and may have a role to play in other cardiovascular disease. Chymase, a protease inhibitor stored in mast cells that generates angiotensin II (Ang II (in addition to angiotensin-converting enzyme [ACE], has been linked to extracellular matrix remodelling in heart failure. Again, chymase inhibitors have been developed to investigate its functions in vitro and in vivo. Bradykinin is thought to contribute to the cardioprotective effect of ACE inhibition through modification of nitric oxide release, calcium handling and collagen accumulation. Ang II is believed to influence a number of molecular and structural changes in the heart, mostly mediated through the AT1-receptor. The importance of the RAAS in heart failure is shown by the survival benefit conferred by treatment with ACE inhibitors.

  14. RETRACTED: Role of renin-angiotensin-aldosterone system inhibitors in radiation nephropathy.

    Science.gov (United States)

    Zhou, Tian-Biao; Li, Hong-Yan; Jiang, Zong-Pei; Zhou, Jia-Fan; Huang, Miao-Fang; Zhou, Zhi-Yang

    2015-12-01

    The following article has been included in a multiple retraction: Tian-Biao Zhou, Hong-Yan Li, Zong-Pei Jiang, Jia-Fan Zhou, Miao-Fang Huang and Zhi-Yang Zhou Role of renin-angiotensin-aldosterone system inhibitors in radiation nephropathy Journal of Renin-Angiotensin-Aldosterone System ( JRAAS) 1470320314563424, first published 18 December 2014. DOI: 10.1177/1470320314563424 . This article has been retracted at the request of the Editors and the Publisher. After conducting a thorough investigation, SAGE found that the submitting authors of a number of papers published in the JRAAS (listed below) had supplied fabricated contact details for their nominated reviewers. The Editors accepted these papers based on the reports supplied by the individuals using these fake reviewer email accounts. After concluding that the peer-review process was therefore seriously compromised, SAGE and the journal Editors have decided to retract all affected articles. Online-first articles (these articles will not be published in an issue) Wenzhuang Tang, Tian-Biao Zhou and Zongpei Jiang Association of the angiotensinogen M235T gene polymorphism with risk of diabetes mellitus developing into diabetic nephropathy JRAAS 1470320314563426, first published 18 December 2014. DOI: 10.1177/1470320314563426 . Tian-Biao Zhou, Hong-Yan Li, Zong-Pei Jiang, Jia-Fan Zhou, Miao-Fang Huang and Zhi-Yang Zhou Role of renin-angiotensin-aldosterone system inhibitors in radiation nephropathy JRAAS 1470320314563424, first published 18 December 2014. DOI: 10.1177/1470320314563424 . Weiqiang Zhong, Zongpei Jiang and Tian-Biao Zhou Association between the ACE I/D gene polymorphism and T2DN susceptibility: The risk of T2DM developing into T2DN in the Asian population JRAAS1470320314566019, first published 26 January 2015. DOI: 10.1177/1470320314566019 . Tian-Biao Zhou, Xue-Feng Guo, Zongpei Jiang and Hong-Yan Li Relationship between the ACE I/D gene polymorphism and T1DN susceptibility/risk of T1DM developing into

  15. Influence of Angiotensin-Aldosterone System on Ultrasound of Joints in Patients with Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    O.B. Komarova

    2014-02-01

    Full Text Available In patients with rheumatoid arthritis and high level of angiotensin II in the blood at ultrasound of joints there are often being detected effusion in the joint cavity, hypervascularization of synovium with 2–3 points and tenosynovitis characterizing inflammatory exudative processes. In patients with high level of aldosterone, hyperplasia of synovium, presence of pannus and bone and cartilage erosions, indicating proliferative-destructive processes, were predominated. Identified correlations show that with increasing levels of angiotensin II in the blood increases the intensity of the vascularization of the synovial membrane, joint effusion, and an increase in the concentration of aldosterone in the blood affects the synovial thickness indicators, the presence of pannus and bone erosions amount.

  16. Dysregulated renin-angiotensin-aldosterone system contributes to pulmonary arterial hypertension

    Science.gov (United States)

    De Man, Frances; Tu, Ly; Handoko, Louis; Rain, Silvia; Ruiter, Gerrina; François, Charlène; Schalij, Ingrid; Dorfmüller, Peter; Simonneau, Gérald; Fadel, Elie; Perros, Frederic; Boonstra, Anco; Postmus, Piet; Van Der Velden, Jolanda; Vonk-Noordegraaf, Anton; Humbert, Marc; Eddahibi, Saadia; Guignabert, Christophe

    2012-01-01

    Rationale Patients with idiopathic pulmonary arterial hypertension (iPAH) often have a low cardiac output. To compensate, neurohormonal systems like renin-angiotensin-aldosterone system (RAAS) and sympathetic nervous system are upregulated but this may have long-term negative effects on the progression of iPAH. Objectives Assess systemic and pulmonary RAAS-activity in iPAH-patients and determine the efficacy of chronic RAAS-inhibition in experimental PAH. Measurements and Main Results We collected 79 blood samples from 58 iPAH-patients in the VU University Medical Center Amsterdam (between 2004–2010), to determine systemic RAAS-activity. We observed increased levels of renin, angiotensin (Ang) I and AngII, which was associated with disease progression (p<0.05) and mortality (p<0.05). To determine pulmonary RAAS-activity, lung specimens were obtained from iPAH-patients (during lung transplantation, n=13) and controls (during lobectomy or pneumonectomy for cancer, n=14). Local RAAS-activity in pulmonary arteries of iPAH-patients was increased, demonstrated by elevated ACE-activity in pulmonary endothelial cells and increased AngII type 1 (AT1) receptor expression and signaling. In addition, local RAAS- upregulation was associated with increased pulmonary artery smooth muscle cell proliferation via enhanced AT1-receptor signaling in iPAH-patients compared to controls. Finally, to determine the therapeutic potential of RAAS-activity, we assessed the chronic effects of an AT1-receptor antagonist (losartan) in the monocrotaline PAH-rat model (60 mg/kg). Losartan delayed disease progression, decreased RV afterload and pulmonary vascular remodeling and restored right ventricular-arterial coupling in PAH-rats. Conclusions Systemic and pulmonary RAAS-activities are increased in iPAH-patients and associated with increased pulmonary vascular remodeling. Chronic inhibition of RAAS by losartan is beneficial in experimental PAH. PMID:22859525

  17. The renin-angiotensin-aldosterone system (RAAS – physiology and molecular mechanisms of functioning

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    Monika Chaszczewska-Markowska

    2016-09-01

    Full Text Available Secretion of renin juxtaglomerular cells into bloodstream initiates activation of an enzymatic-hormonal cascade known as the RAAS (renin – angiotensinaldosterone system. As a result, blood pressure is increased by the means several interrelated mechanisms. Mechanism of Zjednoczoaction of this system has been known for decades, but a few previously unknown components were recently added, such as ACE-2 and Ang(1-7, and their role often seems to be opposite to that of the conventional components. Local tissue systems also have important biological functions. They operate largely independently of the systemic activity, and their activity is observed primarily in the kidney, heart, in blood vessels, adrenal gland and nervous system. Angiotensin-2 (Ang-2, the main RAAS effector, has a wide scope of action, and thus abnormalities in its functioning have many consequences. Excessive activation is accompanied by chronic inflammation, as Ang-2 stimulates inflammatory mediators. As a result, degenerative processes and atherosclerosis are initiated. RAAS imbalance is associated with the most common diseases of civilization, such as cardio-vascular diseases, diabetes, kidney diseases, preeclampsia, osteoporosis and even neurodegenerative diseases. Many of these pathological processes are attributed to the excessive activation of tissue RA system. Therapeutic strategies based on inhibition of the RAAS are commonly used mainly in the treatment of hypertension and other cardiovascular disorders. The benefits of this class of drugs is primarily a decrease in blood pressure, but also the suppression of inflammatory processes and other pathological phenomena resulting from excessive activation of the RAAS. For that reason, some consider to use RAAS inhibitors in other diseases, e.g. Parkinson’s disease. Further studies give hope for the improvement of RAAS inhibitor therapy and the development of new therapeutic strategies

  18. Effects of aqueous extract of Hibiscus sabdariffa on the renin-angiotensin-aldosterone system of Nigerians with mild to moderate essential hypertension: A comparative study with lisinopril

    OpenAIRE

    Nwachukwu, Daniel Chukwu; Aneke, Eddy Ikemefuna; Obika, Leonard Fidelis; Nwachukwu, Nkiru Zuada

    2015-01-01

    Objectives: The present study investigated the effects of aqueous extract of Hibiscus sabdariffa (HS) on the three basic components of renin-angiotensin-aldosterone system: Plasma renin, serum angiotensin-converting enzyme (ACE), and plasma aldosterone (PA) in mild to moderate essential hypertensive Nigerians and compared with that of lisinopril, an ACE inhibitor. Materials and Methods: A double-blind controlled randomized clinical study was used. Seventy-eight newly diagnosed but untreate...

  19. Modulation of the cardiac sodium/bicarbonate cotransporter by the renin angiotensin aldosterone system: pathophysiological consequences.

    Science.gov (United States)

    De Giusti, Verónica C; Ciancio, María C; Orlowski, Alejandro; Aiello, Ernesto A

    2013-01-01

    The sodium/bicarbonate cotransporter (NBC) is one of the major alkalinizing mechanisms in the cardiomyocytes. It has been demonstrated the existence of at least two functional isoforms, one that promotes the co-influx of 1 molecule of Na(+) per 1 molecule of HCO(-) 3 (electroneutral isoform; NBCn1) and the other one that generates the co-influx of 1 molecule of Na(+) per 2 molecules of HCO(-) 3 (electrogenic isoform; NBCe1). Both isoforms are important to maintain intracellular pH (pH i ) and sodium concentration ([Na(+)] i ). In addition, NBCe1 generates an anionic repolarizing current that modulates the action potential duration (APD). The renin-angiotensin-aldosterone system (RAAS) is implicated in the modulation of almost all physiological cardiac functions and is also involved in the development and progression of cardiac diseases. It was reported that angiotensin II (Ang II) exhibits an opposite effect on NBC isoforms: it activates NBCn1 and inhibits NBCe1. The activation of NBCn1 leads to an increase in pH i and [Na(+)] i , which indirectly, due to the stimulation of reverse mode of the Na(+)/Ca(2+) exchanger (NCX), conduces to an increase in the intracellular Ca(2+) concentration. On the other hand, the inhibition of NBCe1 generates an APD prolongation, potentially representing a risk of arrhythmias. In the last years, the potentially altered NBC function in pathological scenarios, as cardiac hypertrophy and ischemia-reperfusion, has raised increasing interest among investigators. This review attempts to draw the attention on the relevant regulation of NBC activity by RAAS, since it modulates pH i and [Na(+)] i , which are involved in the development of cardiac hypertrophy, the damage produced by ischemia-reperfusion and the generation of arrhythmic events, suggesting a potential role of NBC in cardiac diseases.

  20. Introductory statement: Of receptors and analogs in renin-angiotensin-aldosterone and adrenergic systems

    International Nuclear Information System (INIS)

    Eliahou, H.E.; Iaina, A.

    1980-01-01

    This article reports on the role of the octapeptides angiotensin II (A II)-effector and its receptor on hypertensive patients and in animal experiments. By applying the A-II-receptor blockers, vasodilates drugs, β-receptor blockers and by sodium depletion, the behaviour of the blood pressure, the plasmareninactivity, and of the aldosteron were investigated; a comparative investigation between the A II and A III effectors was also carried out. The iodo-hippurate uptake was reduced with an artificially produced renal arterial ischemia. In general, this investigation provided new viewpoints in the understanding of the possible pathogenetic mechanism of essential hypertonism. (APR) [de

  1. [Changes in the renin-angiotensin-aldosterone system and water-salt exchange in mining workers in coal mines].

    Science.gov (United States)

    Rebrov, B A

    1996-01-01

    Blood and urine content of electrolytes and creatinine was determined in 76 essentially healthy miners before and after work shift, as was activity of plasma renin, blood plasma level of aldosterone and its urinary excretion, with the aid of radioimmunoassay. The greatest activity of the renin-angiotensine-aldosterone system (RAAS) occurred in those individuals engaged in hard physical labour under most harsh conditions of underground workings, this being recordable not only is response to the load but also from the very start. Controls and miners doing jobs of medium-level strenuousness demonstrated changes in the correlations between RAAS and water-salt balance after the work shift as compared with those before the work shift, while in those miners engaged in hard work correlations RAAS-water-salt exchange remained practically the same throughout the study.

  2. The Renin-Angiotensin-Aldosterone system in patients with depression compared to controls – a sleep endocrine study

    Directory of Open Access Journals (Sweden)

    Künzel Heike

    2003-10-01

    Full Text Available Abstract Background Hypercortisolism as a sign of hypothamamus-pituitary-adrenocortical (HPA axis overactivity and sleep EEG changes are frequently observed in depression. Closely related to the HPA axis is the renin-angiotensin-aldosterone system (RAAS as 1. adrenocorticotropic hormone (ACTH is a common stimulus for cortisol and aldosterone, 2. cortisol release is suppressed by mineralocorticoid receptor (MR agonists 3. angiotensin II (ATII releases CRH and vasopressin from the hypothalamus. Furthermore renin and aldosterone secretion are synchronized to the rapid eyed movement (REM-nonREM cycle. Methods Here we focus on the difference of sleep related activity of the RAAS between depressed patients and healthy controls. We studied the nocturnal plasma concentration of ACTH, cortisol, renin and aldosterone, and sleep EEG in 7 medication free patients with depression (1 male, 6 females, age: (mean +/-SD 53.3 ± 14.4 yr. and 7 age matched controls (2 males, 5 females, age: 54.7 ± 19.5 yr.. After one night of accommodation a polysomnography was performed between 23.00 h and 7.00 h. During examination nights blood samples were taken every 20 min between 23.00 h and 7.00 h. Area under the curve (AUC for the hormones separated for the halves of the night (23.00 h to 3.00 h and 3.00 h to 7.00 h were used for statistical analysis, with analysis of co variance being performed with age as a covariate. Results No differences in ACTH and renin concentrations were found. For cortisol, a trend to an increase was found in the first half of the night in patients compared to controls (p Conclusion Hyperaldosteronism could be a sensitive marker for depression. Further our findings point to an altered renal mineralocorticoid sensitivity in patients with depression.

  3. Pooled Analysis of Multiple Crossover Trials To Optimize Individual Therapy Response to Renin-Angiotensin-Aldosterone System Intervention

    DEFF Research Database (Denmark)

    Petrykiv, Sergei I.; Laverman, Gozewijn Dirk; Persson, Frederik

    2017-01-01

    BACKGROUND AND OBJECTIVES: In the treatment of CKD, individual patients show a wide variation in their response to many drugs, including renin-angiotensin-aldosterone system inhibitors (RAASi). To investigate whether therapy resistance to RAASi can be overcome by uptitrating the dose of drug......, changing the mode of intervention (with drugs from similar or different classes), or lowering dietary sodium intake, we meta-analyzed individual responses to different modes of interventions. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Randomized crossover trials were analyzed to assess correlation...... of individual responses to RAASi and nonsteroidal anti-inflammatory drugs (NSAIDs; n=395 patients). Included studies compared the antialbuminuric effect of uptitrating the dose of RAASi (n=10 studies) and NSAIDs (n=1), changing within the same class of RAASi (e.g., angiotensin-converting enzyme inhibition...

  4. Activation of renin-angiotensin-aldosterone system (RAAS) in the lung of smoking-induced pulmonary arterial hypertension (PAH) rats.

    Science.gov (United States)

    Yuan, Yi-Ming; Luo, Li; Guo, Zhen; Yang, Ming; Ye, Ren-Song; Luo, Chuan

    2015-06-01

    To explore the role of the renin-angiotensin-aldosterone system (RAAS) in the pathogenesis of pulmonary arterial hypertension (PAH) induced by chronic exposure to cigarette smoke. 48 healthy male SD rats were randomly divided into four groups (12/group): control group (group A); inhibitor alone group (group B); cigarette induction group (group C); cigarette induction + inhibitor group (group D). After the establishment of smoking-induced PAH rat model, the right ventricular systolic pressure (RVSP) was detected using an inserted catheter; western blotting was used to detect the protein expression of angiotensin-converting enzyme-2 (ACE2) and angiotensin-converting enzyme (ACE); expression levels of angiotensin II (AngII) in lung tissue were measured by radioimmunoassay. After six months of cigarette exposure, the RVSP of chronic cigarette induction group was significantly higher than that of the control group; expression levels of AngII and ACE increased in lung tissues, but ACE2 expression levels reduced. Compared with cigarette exposure group, after losartan treatment, RVSP, ACE and AngII obviously decreased (Psmoking-induced PAH. © The Author(s) 2015.

  5. Effects of warming yang and invigorating qi prescription on renin-angiotensin-aldosterone system in rats with heart failure after myocardial infarction

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    Lihua HAN

    Full Text Available Abstract This study investigated the effects of warming yang and invigorating qi prescription on renin-angiotensin-aldosterone system (RAAS in rats with heart failure after myocardial infarction. 126 rats were randomly divided into model group, sham operation, warming yang, invigorating qi, warming yang+invigorating qi, digoxin and captopril group for respective treatment. After intervention for 6, 8 and 10 weeks, the left ventricular ejection fraction (LVEF was calculated, and the plasma renin, angiotensin II and aldosterone levels were measured. Results showed that, after 6, 8 and 10 weeks, LVEF in warming yang, invigorating qi, warming yang+invigorating qi and captopril group was significantly higher than model group (P < 0.05, and the plasma renin, angiotensin II and aldosterone levels in warming yang, invigorating qi, warming yang+invigorating qi and captopril groups were significantly lower than model group (P < 0.05. Renin angiotensin II and aldosterone levels in invigorating qi, warming yang+invigorating qi and captopril groups after 10 weeks was significantly lower than after 6 weeks (P < 0.05; aldosterone level in captopril groups after 10 weeks was significantly lower than after 6 weeks (P < 0.05. Warming yang and invigorating qi prescription can improve LVEF in rats with heart failure after myocardial infarction, which may be related with the inhibition of RAAS activation.

  6. Association studies suggest a key role for endothelin-1 in the pathogenesis of preeclampsia and the accompanying renin-angiotensin-aldosterone system suppression.

    Science.gov (United States)

    Verdonk, Koen; Saleh, Langeza; Lankhorst, Stephanie; Smilde, J E Ilse; van Ingen, Manon M; Garrelds, Ingrid M; Friesema, Edith C H; Russcher, Henk; van den Meiracker, Anton H; Visser, Willy; Danser, A H Jan

    2015-06-01

    Women with preeclampsia display low renin-angiotensin-aldosterone system activity and a high antiangiogenic state, the latter characterized by high levels of soluble Fms-like tyrosine kinase (sFlt)-1 and reduced placental growth factor levels. To investigate whether renin-angiotensin-aldosterone system suppression in preeclampsia is because of this disturbed angiogenic balance, we measured mean arterial pressure, creatinine, endothelin-1 (ET-1), and renin-angiotensin-aldosterone system components in pregnant women with a high (≥85; n=38) or low (<85; n=65) soluble Fms-like tyrosine kinase-1/placental growth factor ratio. Plasma ET-1 levels were increased in women with a high ratio, whereas their plasma renin activity and plasma concentrations of renin, angiotensinogen, and aldosterone were decreased. Plasma renin activity-aldosterone relationships were identical in both the groups. Multiple regression analysis revealed that plasma renin concentration correlated independently with mean arterial pressure and plasma ET-1. Plasma ET-1 correlated positively with soluble Fms-like tyrosine kinase-1 and negatively with plasma renin concentration, and urinary protein correlated with plasma ET-1 and mean arterial pressure. Despite the lower plasma levels of renin and angiotensinogen in the high-ratio group, their urinary levels of these components were elevated. Correction for albumin revealed that this was because of increased glomerular filtration. Subcutaneous arteries obtained from patients with preeclampsia displayed an enhanced, AT2 receptor-mediated response to angiotensin II. In conclusion, a high antiangiogenic state associates with ET-1 activation, which together with the increased mean arterial pressure may underlie the parallel reductions in renin and aldosterone in preeclampsia. Because ET-1 also was a major determinant of urinary protein, our data reveal a key role for ET-1 in the pathogenesis of preeclampsia. Finally, the enhanced angiotensin responsiveness

  7. Multilocus analyses of renin-angiotensin-aldosterone system gene variants on blood pressure at rest and during behavioral stress in young normotensive subjects

    NARCIS (Netherlands)

    Ge, Dongliang; Zhu, Haidong; Huang, Ying; Treiber, Frank A.; Harshfield, Gregory A.; Snieder, Harold; Dong, Yanbin

    The renin-angiotensin-aldosterone system (RAAS) is a proteolytic cascade that regulates and maintains blood pressure (BP). This study aimed to explore the interactive and integrative effects of multiple RAAS polymorphisms on BP at rest and during behavioral stress in a normotensive population. A

  8. Effects of Dietary Sodium Restriction in Kidney Transplant Recipients Treated With Renin-Angiotensin-Aldosterone System Blockade: A Randomized Clinical Trial

    NARCIS (Netherlands)

    de Vries, Laura V.; Dobrowolski, Linn C.; van den Bosch, Jacqueline J. O. N.; Riphagen, Ineke J.; Krediet, C. T. Paul; Bemelman, Frederike J.; Bakker, Stephan J. L.; Navis, Gerjan

    2016-01-01

    In patients with chronic kidney disease receiving renin-angiotensin-aldosterone system (RAAS) blockade, dietary sodium restriction is an often-used treatment strategy to reduce blood pressure (BP) and albuminuria. Whether these effects extend to kidney transplant recipients is unknown. We therefore

  9. Effects of Dietary Sodium Restriction in Kidney Transplant Recipients Treated With Renin-Angiotensin-Aldosterone System Blockade : A Randomized Clinical Trial

    NARCIS (Netherlands)

    de Vries, Laura V; Dobrowolski, Linn C; van den Bosch, Jacqueline J O N; Riphagen, Ineke J; Krediet, C T Paul; Bemelman, Frederike J; Bakker, Stephan J L; Navis, Gerjan

    BACKGROUND: In patients with chronic kidney disease receiving renin-angiotensin-aldosterone system (RAAS) blockade, dietary sodium restriction is an often-used treatment strategy to reduce blood pressure (BP) and albuminuria. Whether these effects extend to kidney transplant recipients is unknown.

  10. The Relationship Between the Renin-Angiotensin-Aldosterone System and NMDA Receptor-Mediated Signal and the Prevention of Retinal Ganglion Cell Death.

    Science.gov (United States)

    Kobayashi, Mamoru; Hirooka, Kazuyuki; Ono, Aoi; Nakano, Yuki; Nishiyama, Akira; Tsujikawa, Akitaka

    2017-03-01

    Excitotoxicity, which is due to glutamate-induced toxic effects on the retinal ganglion cell (RGC), is one of several mechanisms of RGC loss. The renin-angiotensin-aldosterone system (RAAS) has also been implicated in RGC death. Therefore, it is important to determine the exact relationship between the RAAS and N-methyl-d-aspartate (NMDA) receptor-mediated signal in order to prevent RGC death. N-methyl-d-aspartate or aldosterone was injected into the vitreous body. After intravitreal injection of NMDA or aldosterone, animals were treated with spironolactone or memantine. Retinal damage was evaluated by measuring the number of RGCs at 4 weeks after local administration of aldosterone or at 2 weeks after local administration of NMDA. Vitreous humor levels of aldosterone were measured using enzyme immunoassay kits. A significantly decreased number of RGCs were observed after intravitreal injection of NMDA. Although spironolactone did not show any neuroprotective effects, memantine significantly reduced NMDA-induced degeneration in the retina. Furthermore, a significant decrease in the number of RGCs was observed after an intravitreal injection of aldosterone. While memantine did not exhibit any neuroprotective effects, spironolactone caused a significant reduction in the aldosterone-induced degeneration in the retina. There was no change in the aldosterone concentration in the vitreous humor after an NMDA injection. Our findings indirectly show that there is no relationship between the RAAS and NMDA receptor-mediated signal with regard to RGC death.

  11. Beneficial long-term effect of aldosterone antagonist added to a traditional blockade of the renin-angiotensin-aldosterone system among patients with obesity and proteinuria.

    Science.gov (United States)

    Morales, Enrique; Gutiérrez, Eduardo; Caro, Jara; Sevillano, Angel; Rojas-Rivera, Jorge; Praga, Manuel

    2015-01-01

    Over the past decade, obesity has become a risk factor for developing chronic kidney disease. Proteinuria is known to be an independent determinant of the progression of chronic kidney disease, and adipose tissue is a recognized source of components of the renin-angiotensin-aldosterone system (RAAS). Recent studies have shown that plasma aldosterone levels are disproportionately higher in patients with obesity. Drugs that block the RAAS are unable to inhibit aldosterone in the long term. The aim of our study was to analyze the renoprotective effect of an aldosterone antagonist in combination with RAAS blockers in patients with obesity and proteinuric nephropathy. This study is a substudy of previously published study on the renoprotective effect of mineralocorticoid receptor blockers in patients with proteinuric nephropathies. Patients with proteinuria levels >1g/24h who were taking spironolactone and were being treated with other RAAS blockers were divided according to body mass index (BMI) into an obesity group (BMI ≥30kg/m2) and a control group. Seventy-one patients were included in the study, with a mean age of 56.7±15.1 years. More than 50% of the patients in both groups had diabetes. Thirty-two patients were included in the obesity group and 39 were included in the control group. There were no significant differences in renal function, proteinuria, blood pressure, serum potassium levels and the percentage of RAAS blockers in both groups. After a follow-up of 28.9 (14-84) months, there was a 59.4% reduction in proteinuria in the obesity group (2.8±2.1 vs. 1.3±1.6g/24h, p<.05). The reduction in proteinuria was greater than 50% in 22 (68.8%) cases, and the mean blood pressure showed a significant decrease (from 100.6±9 to 92.1±7.4mm Hg, p<.05). The control group showed a 69.6% reduction in proteinuria (1.9±1.4 to 0.8±0.5, p<0.05). The reduction of proteinuria was higher than 50% in 22 (68.8%) cases in obese patients and in 33 (84.6%) cases in non

  12. A high sodium intake reduces antiproteinuric response to renin-angiotensin-aldosterone system blockade in kidney transplant recipients.

    Science.gov (United States)

    Monfá, Elena; Rodrigo, Emilio; Belmar, Lara; Sango, Cristina; Moussa, Fozi; Ruiz San Millán, Juan Carlos; Piñera, Celestino; Fernández-Fresnedo, Gema; Arias, Manuel

    Post-transplant proteinuria is associated with lower graft and patient survival. Renin-angiotensin-aldosterone system blockers are used to reduce proteinuria and improve renal outcome. Although it is known that a high salt intake blunts the antiproteinuric effect of ACEI and ARB drugs in non-transplant patients, this effect has not been studied in kidney transplant recipients. To analyse the relationship between sodium intake and the antiproteinuric effect of ACEI/ARB drugs in kidney transplant recipients. We selected 103 kidney transplant recipients receiving ACEI/ARB drugs for more than 6 months due to proteinuria>1 g/day. Proteinuria was analysed at baseline and at 6 months after starting ACEI/ARB treatment. Salt intake was estimated by urinary sodium to creatinine ratio (uNa/Cr). Proteinuria fell to less than 1g/day in 46 patients (44.7%). High uNa/Cr was associated with a smaller proteinuria decrease (r=-0.251, P=.011). The percentage proteinuria reduction was significantly lower in patients in the highest uNa/Cr tertile [63.9% (IQR 47.1%), 60.1% (IQR 55.4%), 38.9% (IQR 85.5%), P=.047]. High uNa/Cr independently relates (OR 2.406 per 100 mEq/g, 95% CI: 1.008-5.745, P=.048) to an antiproteinuric response <50% after renin-angiotensin-aldosterone system blockade. A high salt intake results in a smaller proteinuria decrease in kidney transplant recipients with proteinuria treated with ACEI/ARB drugs. Copyright © 2016 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  13. The role of tissue renin angiotensin aldosterone system in the development of endothelial dysfunction and arterial stiffness

    Directory of Open Access Journals (Sweden)

    Annayya R Aroor

    2013-10-01

    Full Text Available Epidemiological studies support the notion that arterial stiffness is an independent predictor of adverse cardiovascular events contributing significantly to systolic hypertension, impaired ventricular-arterial coupling and diastolic dysfunction, impairment in myocardial oxygen supply and demand, and progression of kidney disease. Although arterial stiffness is associated with aging, it is accelerated in the presence of obesity and diabetes. The prevalence of arterial stiffness parallels the increase of obesity that is occurring in epidemic proportions and is partly driven by a sedentary life style and consumption of a high fructose, high salt and high fat western diet. Although the underlying mechanisms and mediators of arterial stiffness are not well understood, accumulating evidence supports the role of insulin resistance and endothelial dysfunction. The local tissue renin angiotensin aldosterone system (RAAS in the vascular tissue and immune cells and perivascular adipose tissue is recognized as an important element involved in endothelial dysfunction which contributes significantly to arterial stiffness. Activation of vascular RAAS is seen in humans and animal models of obesity and diabetes, and associated with enhanced oxidative stress and inflammation in the vascular tissue. The cross talk between angiotensin and aldosterone underscores the importance of mineralocorticoid receptors in modulation of insulin resistance, decreased bioavailability of nitric oxide, endothelial dysfunction and arterial stiffness. In addition, both innate and adaptive immunity are involved in this local tissue activation of RAAS. In this review we will attempt to present a unifying mechanism of how environmental and immunological factors are involved in this local tissue RAAS activation, and the role of this process in the development of endothelial dysfunction and arterial stiffness and targeting tissue RAAS activation.

  14. KCNQ1 A340E impairs electrolyte homeostasis independently of the renin-angiotensin-aldosterone system in mice.

    Science.gov (United States)

    Pan, Q; Sang, Y; Sun, C; Li, G; Wang, Y

    2016-07-25

    KCNQ1 (KvLQT1) is the pore-forming a-subunit of the potassium channel. To uncover its role in electrolyte metabolism, we investigated the effects of KCNQ1 A340E, a loss-of-function mutant, on J343 mice. Compared with the normal controls (C57BL/6J mice) bearing the wild-type KCNQ1 gene, J343 mice bearing KCNQ1 A340E demonstrated a much higher 24-h intake of electrolytes (potassium, sodium, and chloride). However, they suffered from significant electrolyte loss through both the feces and urine during a period of 24 h. Unbalance in electrolyte metabolism disrupted the electrolyte homeostasis in the J343 mice, which was characterized by the comparatively lower level of serum potassium (J343 vs C57BL/6J: 12.06 ± 1.47 vs 14.44 ± 3.58 mM, P = 0.01) and higher levels of serum sodium (J343 vs C57BL/6J: 148.05 ± 4.47 vs 115.15 ± 17.25 mM, P = 4.20 x 10(-4)) and chloride (J343 vs C57BL/6J: 118.0 ± 4.47 vs 85.21 ± 11.90 mM, P = 2.47 x 10(-5)). Between the J343 and C57BL/6J mice, there was no statistically significant difference in KCNQ1 expression in the gastrointestinal tract and kidney. Normal concentrations of plasma renin, angiotensin I, and aldosterone were also detected in both lines of mice. KCNQ1, therefore, is suggested to play a central role in electrolyte metabolism. KCNQ1 A340E, with the loss-of-function phenotype, may dysregulate electrolyte homeostasis in mice independently of the activity of the renin-angiotensin-aldosterone system.

  15. Recombinant erythropoietin acutely decreases renal perfusion and decouples the renin-angiotensin-aldosterone system

    DEFF Research Database (Denmark)

    Aachmann-Andersen, Niels J.; Christensen, Soren J.; Lisbjerg, Kristian

    2018-01-01

    The effect of recombinant erythropoietin (rhEPO) on renal and systemic hemodynamics was evaluated in a randomized double-blinded, cross-over study. Sixteen healthy subjects were tested with placebo, or low-dose rhEPO for 2 weeks, or high-dose rhEPO for 3 days. Subjects refrained from excessive salt...... intake, according to instructions from a dietitian. Renal clearance studies were done for measurements of renal plasma flow, glomerular filtration rate (GFR) and the segmentel tubular handling of sodium and water (lithium clearance). rhEPO increased arterial blood pressure, total peripheral resistance...... of renin and aldosterone, independent of changes in red blood cell mass, blood volumes, and blood pressure. We also found changes in biomarkers showing evidence that rhEPO induced a prothrombotic state. Our results suggest that rhEPO causes a direct downregulation in proximal tubular reabsorption...

  16. Upregulation of the Renin-Angiotensin-Aldosterone-Ouabain System in the Brain Is the Core Mechanism in the Genesis of All Types of Hypertension

    Directory of Open Access Journals (Sweden)

    Hakuo Takahashi

    2012-01-01

    Full Text Available Basic research using animal models points to a causal role of the central nervous system in essential hypertension; however, since clinical research is technically difficult to perform, this connection has not been confirmed in humans. Recently, renal nerve ablation in humans proved to continuously decrease blood pressure in resistant hypertension. Furthermore, when electrical stimulation was continuously applied to the carotid baroreceptor nerve of human adults, their blood pressure lowered. These findings promoted the concept that the central nervous system may actually be involved in the pathogenesis of essential hypertension, which is closely associated with excess sodium intake. We have demonstrated that endogenous digitalis plays a key role in hypertension associated with excess sodium intake via sympathetic activation in rats. Increased sodium concentration inside the brain activates epithelial sodium channels and the renin-angiotensin-aldosterone system in the brain. Aldosterone releases ouabain from neurons in the paraventricular nucleus in the hypothalamus. Angiotensin II and aldosterone of peripheral origin reach the brain to augment sympathetic outflow. Collectively essential hypertension associated with excess sodium intake and obesity, renovascular hypertension, and primary aldosteronism and pseudoaldosteronism all seem to have a common cause originating from the central nervous system.

  17. Role of the Renin-Angiotensin-Aldosterone System beyond Blood Pressure Regulation: Molecular and Cellular Mechanisms Involved in End-Organ Damage during Arterial Hypertension.

    Science.gov (United States)

    Muñoz-Durango, Natalia; Fuentes, Cristóbal A; Castillo, Andrés E; González-Gómez, Luis Martín; Vecchiola, Andrea; Fardella, Carlos E; Kalergis, Alexis M

    2016-06-23

    Arterial hypertension is a common condition worldwide and an important predictor of several complicated diseases. Arterial hypertension can be triggered by many factors, including physiological, genetic, and lifestyle causes. Specifically, molecules of the renin-angiotensin-aldosterone system not only play important roles in the control of blood pressure, but they are also associated with the genesis of arterial hypertension, thus constituting a need for pharmacological interventions. Chronic high pressure generates mechanical damage along the vascular system, heart, and kidneys, which are the principal organs affected in this condition. In addition to mechanical stress, hypertension-induced oxidative stress, chronic inflammation, and the activation of reparative mechanisms lead to end-organ damage, mainly due to fibrosis. Clinical trials have demonstrated that renin-angiotensin-aldosterone system intervention in hypertensive patients lowers morbidity/mortality and inflammatory marker levels as compared to placebo patients, evidencing that this system controls more than blood pressure. This review emphasizes the detrimental effects that a renin-angiotensin-aldosterone system (RAAS) imbalance has on health considerations above and beyond high blood pressure, such as fibrotic end-organ damage.

  18. Role of the Renin-Angiotensin-Aldosterone System beyond Blood Pressure Regulation: Molecular and Cellular Mechanisms Involved in End-Organ Damage during Arterial Hypertension

    Directory of Open Access Journals (Sweden)

    Natalia Muñoz-Durango

    2016-06-01

    Full Text Available Arterial hypertension is a common condition worldwide and an important predictor of several complicated diseases. Arterial hypertension can be triggered by many factors, including physiological, genetic, and lifestyle causes. Specifically, molecules of the renin-angiotensin-aldosterone system not only play important roles in the control of blood pressure, but they are also associated with the genesis of arterial hypertension, thus constituting a need for pharmacological interventions. Chronic high pressure generates mechanical damage along the vascular system, heart, and kidneys, which are the principal organs affected in this condition. In addition to mechanical stress, hypertension-induced oxidative stress, chronic inflammation, and the activation of reparative mechanisms lead to end-organ damage, mainly due to fibrosis. Clinical trials have demonstrated that renin-angiotensin-aldosterone system intervention in hypertensive patients lowers morbidity/mortality and inflammatory marker levels as compared to placebo patients, evidencing that this system controls more than blood pressure. This review emphasizes the detrimental effects that a renin-angiotensin-aldosterone system (RAAS imbalance has on health considerations above and beyond high blood pressure, such as fibrotic end-organ damage.

  19. Therapeutic Approaches in Lowering Albuminuria : Travels Along the Renin-Angiotensin-Aldosterone-System Pathway

    NARCIS (Netherlands)

    Lambers Heerspink, Hiddo J.

    Achieving optimal blood pressure and albuminuria control is a major therapeutic treatment goal in patients with renal insufficiency. Angiotensin-converting enzyme-inhibitors (ACEIs) and angiotensin-receptor blockers (ARB) are the mainstay of therapy in these patients. However, despite these

  20. New perspectives in the renin-angiotensin-aldosterone system (RAAS) II: albumin suppresses angiotensin converting enzyme (ACE) activity in human.

    Science.gov (United States)

    Fagyas, Miklós; Úri, Katalin; Siket, Ivetta M; Fülöp, Gábor Á; Csató, Viktória; Daragó, Andrea; Boczán, Judit; Bányai, Emese; Szentkirályi, István Elek; Maros, Tamás Miklós; Szerafin, Tamás; Édes, István; Papp, Zoltán; Tóth, Attila

    2014-01-01

    About 8% of the adult population is taking angiotensin-converting enzyme (ACE) inhibitors to treat cardiovascular disease including hypertension, myocardial infarction and heart failure. These drugs decrease mortality by up to one-fifth in these patients. We and others have reported previously that endogenous inhibitory substances suppress serum ACE activity, in vivo, similarly to the ACE inhibitor drugs. Here we have made an effort to identify this endogenous ACE inhibitor substance. ACE was crosslinked with interacting proteins in human sera. The crosslinked products were immunoprecipitated and subjected to Western blot. One of the crosslinked products was recognized by both anti-ACE and anti-HSA (human serum albumin) antibodies. Direct ACE-HSA interaction was confirmed by binding assays using purified ACE and HSA. HSA inhibited human purified (circulating) and human recombinant ACE with potencies (IC50) of 5.7 ± 0.7 and 9.5 ± 1.1 mg/mL, respectively. Effects of HSA on the tissue bound native ACE were tested on human saphenous vein samples. Angiotensin I evoked vasoconstriction was inhibited by HSA in this vascular tissue (maximal force with HSA: 6.14 ± 1.34 mN, without HSA: 13.54 ± 2.63 mN), while HSA was without effects on angiotensin II mediated constrictions (maximal force with HSA: 18.73 ± 2.17 mN, without HSA: 19.22 ± 3.50 mN). The main finding of this study is that HSA was identified as a potent physiological inhibitor of the ACE. The enzymatic activity of ACE appears to be almost completely suppressed by HSA when it is present in its physiological concentration. These data suggest that angiotensin I conversion is limited by low physiological ACE activities, in vivo.

  1. Role of MicroRNAs in Renin-Angiotensin-Aldosterone System-Mediated Cardiovascular Inflammation and Remodeling

    Directory of Open Access Journals (Sweden)

    Maricica Pacurari

    2015-01-01

    Full Text Available MicroRNAs are endogenous regulators of gene expression either by inhibiting translation or protein degradation. Recent studies indicate that microRNAs play a role in cardiovascular disease and renin-angiotensin-aldosterone system- (RAAS- mediated cardiovascular inflammation, either as mediators or being targeted by RAAS pharmacological inhibitors. The exact role(s of microRNAs in RAAS-mediated cardiovascular inflammation and remodeling is/are still in early stage of investigation. However, few microRNAs have been shown to play a role in RAAS signaling, particularly miR-155, miR-146a/b, miR-132/122, and miR-483-3p. Identification of specific microRNAs and their targets and elucidating microRNA-regulated mechanisms associated RAS-mediated cardiovascular inflammation and remodeling might lead to the development of novel pharmacological strategies to target RAAS-mediated vascular pathologies. This paper reviews microRNAs role in inflammatory factors mediating cardiovascular inflammation and RAAS genes and the effect of RAAS pharmacological inhibition on microRNAs and the resolution of RAAS-mediated cardiovascular inflammation and remodeling. Also, this paper discusses the advances on microRNAs-based therapeutic approaches that may be important in targeting RAAS signaling.

  2. Beta2-adrenergic receptor genotype affects the renin-angiotensin-aldosterone system response to the Dietary Approaches to Stop Hypertension (DASH) dietary pattern.

    Science.gov (United States)

    Sun, Bei; Williams, Jonathan S; Svetkey, Laura P; Kolatkar, Nikheel S; Conlin, Paul R

    2010-08-01

    Beta(2)-adrenergic receptor (beta2-AR) is a susceptibility locus for hypertension, and polymorphisms at this site relate to salt sensitivity and low plasma renin activity (PRA). The Dietary Approaches to Stop Hypertension (DASH) dietary pattern lowers blood pressure and appears to interact with the renin-angiotensin-aldosterone system (RAAS). We hypothesized that the DASH diet associates with increased RAAS activity, and genotype status at beta2-AR G46A modifies this response. We genotyped participants in the DASH-Sodium study (n = 372) at beta2-AR G46A to determine the association with blood pressure, RAAS components, and consumption of the DASH diet. We used 2-way mixed linear regression and an additive model for all primary analyses. Mean (+/-SEM) PRA was significantly higher in participants in the DASH group than in participants in the control group (0.68 +/- 0.03 compared with 0.54 +/- 0.03 ng x mL(-1) x h(-1), P = 0.002). Serum aldosterone, urinary aldosterone, and urinary potassium concentrations were also significantly higher in the DASH group (P diet interactions for changes in systolic blood pressure (SBP) and concentrations of aldosterone and urinary potassium (P for interaction = 0.048, 0.017, and 0.001 for SBP and aldosterone and urinary potassium concentrations, respectively). There was an association between the A allele of beta2-AR G46A and greater blood pressure reduction and blunted aldosterone and PRA responses to the DASH diet. Our results indicate that the DASH diet lowers blood pressure and increases PRA and aldosterone concentrations. There is an association between the G46A polymorphism of beta2-AR and blood pressure and RAAS responses to the DASH diet, which suggests that beta2-AR may be a genetic modifier of DASH-diet responsiveness. This trial was registered at clinicaltrials.gov as NCT00000608.

  3. New perspectives in the renin-angiotensin-aldosterone system (RAAS I: endogenous angiotensin converting enzyme (ACE inhibition.

    Directory of Open Access Journals (Sweden)

    Miklós Fagyas

    Full Text Available Angiotensin-converting enzyme (ACE inhibitors represent the fifth most often prescribed drugs. ACE inhibitors decrease 5-year mortality by approximately one-fifth in cardiovascular patients. Surprisingly, there are reports dating back to 1979 suggesting the existence of endogenous ACE inhibitors, which endogenous inhibitory effects are much less characterized than that for the clinically administered ACE inhibitors. Here we aimed to investigate this endogenous ACE inhibition in human sera. It was hypothesized that ACE activity is masked by an endogenous inhibitor, which dissociates from the ACE when its concentration decreases upon dilution. ACE activity was measured by FAPGG hydrolysis first. The specific (dilution corrected enzyme activities significantly increased by dilution of human serum samples (23.2 ± 0.7 U/L at 4-fold dilution, 51.4 ± 0.3 U/L at 32-fold dilution, n = 3, p = 0.001, suggesting the presence of an endogenous inhibitor. In accordance, specific enzyme activities did not changed by dilution when purified renal ACE was used, where no endogenous inhibitor was present (655 ± 145 U/L, 605 ± 42 U/L, n = 3, p = 0.715, respectively. FAPGG conversion strongly correlated with angiotensin I conversion suggesting that this feature is not related to the artificial substrate. Serum samples were ultra-filtered to separate ACE (MW: 180 kDa and the hypothesized inhibitor. Filtering through 50 kDa filters was without effect, while filtering through 100 kDa filters eliminated the inhibiting factor (ACE activity after <100 kDa filtering: 56.4 ± 2.4 U/L, n = 4, control: 26.4 ± 0.7 U/L, n = 4, p<0.001. Lineweaver-Burk plot indicated non-competitive inhibition of ACE by this endogenous factor. The endogenous inhibitor had higher potency on the C-terminal active site than N-terminal active site of ACE. Finally, this endogenous ACE inhibition was also present in mouse, donkey, goat, bovine sera besides men (increasing of specific ACE activity

  4. Radioimmunoassay of renin-angiotensin-aldosterone in patients with adrenal tumors

    International Nuclear Information System (INIS)

    Slavnov, V.N.; Yakovlev, A.A.; Yugrinov, O.G.; Gandzha, T.I.

    1983-01-01

    The results are presented of a study of the renin-angiotensin-aldosterone system in 89 patients with aldosteronoma, corticosteroma, pheochromocytoma and hypertension. Radioimmunoassay was used to measure aldosterone concentration and renin activity in the peripheral blood and blood from vena cava inferior, the renal and adrenal veins, the circadian cycle of their content and the responsiveness of the glomerular zone of the adrenal cortex and the juxtaglomerular renal system under the influence of lasix intake and the change over from a horizontal into vertical position. Patients with adrenal tumors have shown disorders of renin-angiotensin-aldosterone function. Radioimmunoassay of the renin-angiotensin-aldosterone system promotes early detection of adrenal tumors in the general population of patients with hypertension and can be used for control over therapeutic efficacy

  5. 8C.03: A KEY ROLE FOR ENDOTHELIN-1 IN THE PATHOGENESIS OF PREECLAMPSIA AND THE ASSOCIATED SUPPRESSION OF THE RENIN-ANGIOTENSIN-ALDOSTERONE SYSTEM.

    Science.gov (United States)

    Verdonk, K; Saleh, L; Smilde, J E; van Ingen, M M; Garrelds, I M; Friesema, E C; Russcher, H; Steegers, E A P; van den Meiracker, A H; Visser, W; Danser, A H J

    2015-06-01

    Women with preeclampsia (PE) display low renin-angiotensin-aldosterone system (RAAS) activity and a high anti-angiogenic state, the latter characterized by high levels of soluble Fms-like tyrosine kinase-1(sFlt-1) and reduced levels of placental growth factor (PlGF). In the present study, we hypothesized that the RAAS suppression in PE is the consequence of the disturbed angiogenic balance. In a group of pregnant women with hypertensive disease of pregnancy and a group of healthy pregnant women, matched for gestational age (GA) we measured mean arterial blood pressure (MAP), urinary protein-to-creatinine ratio (PCR), and the plasma levels of sFlt-1, PlGF, albumin, creatinine, endothelin-1 (ET-1), renin (concentration and activity, PRC and PRA), angiotensinogen, and aldosterone. Since initial analysis revealed that these parameters strongly correlated with each other, multiple regression analysis was applied to establish independent determinants of ET-1, PRC, aldosterone and PCR. A sFlt-1/PlGF ratio >85 was considered to be representative for a high anti-angiogenic state. Of the 103 pregnant women included, 65 had a sFlt-1/PlGF ratio 85. Plasma ET-1 and creatinine levels were increased in women with a high ratio, whereas PRA and the plasma levels of renin, angiotensinogen, aldosterone and albumin were decreased in these women. The PRA-aldosterone relationship was identical in both groups. Multiple regression analysis revealed that PRC correlated independently with MAP and plasma ET-1 (R2 0.30). In turn, plasma ET-1 correlated positively with sFlt-1 and negatively with PRC (R2 0.52). Independent determinants of plasma aldosterone were GA and PRA (R2 0.56). Finally we found that plasma PlGF, plasma ET-1 and MAP determined PCR (R2 0.69). The high anti-angiogenic state in PE induces ET-1 activation. Together with the increased MAP in PE this factor suppresses renin release, and in parallel (via PRA reduction) aldosterone synthesis. The identical reduction in PRA and

  6. Renin-angiotensin-aldosterone system inhibitors lower hemoglobin and hematocrit only in renal transplant recipients with initially higher levels.

    Science.gov (United States)

    Mikolasevic, I; Zaputovic, L; Zibar, L; Begic, I; Zutelija, M; Klanac, A; Majurec, I; Simundic, T; Minazek, M; Orlic, L

    2016-04-01

    We have analyzed the effects of renin-angiotensin-aldosterone system (RAAS) inhibitors on evolution of hemoglobin (Hb) and hematocrit (Htc) levels as well as on the evaluation of kidney graft function in stable renal transplant recipients (RTRs) in respect with initially higher or lower Hb and Htc values. The study group comprised of 270 RTRs with stable graft function. Besides other prescribed antihypertensive therapy, 169 of them have been taking RAAS inhibitors. We wanted to analyze the effect of the use of RAAS inhibitors on Hb and Htc in patients with initially higher or lower Hb/Htc values. For this analysis, only RTRs that were taking RAAS inhibitors were stratified into two groups: one with higher Hb and Htc (initial Hb≥150g/L and Htc≥45%) and another one with lower Hb and Htc (initial Hb<150g/L and Htc<45%) values. Thirty-four RTRs with initially higher Hb and 41 RTRs with initially higher Htc had a statistically significant decrease in Hb (p=0.006) and Htc (p<0.0001) levels after 12-months of follow-up. In the group of patients with initially lower Hb (135 RTRs) and Htc (128 RTRs) there was a significant increase in Hb (p=0.0001) and Htc (p=0.004) levels through the observed period. The use of RAAS inhibitors has been associated with a trend of slowing renal insufficiency in RTRs (p=0.03). RAAS inhibitors lower Hb and Htc only in RTRs with initially higher levels. In patients with initially lower Hb and Htc levels, the use of these drugs is followed by beneficial impact on erythropoiesis and kidney graft function. Copyright © 2015 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

  7. Human in vivo study of the renin-angiotensin-aldosterone system and the sympathetic activity after 8 weeks daily intake of fermented milk

    DEFF Research Database (Denmark)

    Usinger, Lotte; Ibsen, Hans; Linneberg, Allan

    2010-01-01

    OBJECTIVE: Milk fermented by lactic acid bacteria is suggested to have antihypertensive effect in humans. In vitro and animal studies have established an angiotensin-converting enzyme (ACE) inhibitor effect of peptides in fermented milk. However, other modes of action must be considered, because...... until today no human studies have confirmed an ACE inhibition in relation to the intake of fermented milk. MATERIALS AND METHODS: We undertook a double-blinded randomized placebo-controlled study including 94 borderline-hypertensive persons to study the effect on human physiology of Lactobacillus...... helveticus fermented milk. The subjects were randomized into three groups: Cardi04-300 ml, Cardi04-150 ml or placebo. All components of the renin-angiotensin-aldosterone system were measured several times. Sympathetic activity was estimated by plasma noradrenaline and cardiovascular response to head-up tilt...

  8. Effects of enalapril maleate on blood pressure, renin-angiotensin-aldosterone system, and peripheral sympathetic activity in essential hypertension.

    Science.gov (United States)

    Cerasola, G; Cottone, S; D'Ignoto, G; Grasso, L; Carone, M B; Carapelle, E; Contorno, A

    1987-01-01

    Recent experimental studies showed that inhibition of angiotensin II synthesis may reduce sympathetic activity as evaluated by plasma catecholamine assay, sharing in the antihypertensive effect of angiotensin converting enzyme (ACE) inhibitors. Fifteen patients with essential hypertension were studied. Blood pressure and heart rate were evaluated both at rest and after stressor laboratory tests, before and four hours after administration of 20 mg of enalapril maleate and on the 14th and 120th days of continued administration. At the same time, blood samples were drawn for determinations of plasma renin activity, ACE, angiotensin II, plasma aldosterone concentration, and plasma norepinephrine levels. Enalapril in a dosage of 20 mg/day significantly and progressively lowered systolic and diastolic blood pressure at rest, with maximal decreases observed on the 120th day of the study period (P less than 0.001). Heart rate at rest and after exercise showed no significant differences throughout the study period. Good blood pressure control was observed during stressor laboratory tests. The greatest impact of blood pressure was observed on the 120th day during dynamic exercise (mean blood pressure from 139 +/- 3.9 to 111.5 +/- 6.3 mmHg; P less than 0.01) and on the 14th day during the cold pressure test (mean blood pressure from 133.3 +/- 3.9 to 111.2 +/- 4.7 mmHg; P less than 0.005). A marked and persistent ACE inhibition and a gradual and progressive decrease of angiotensin II (from 12.42 +/- 2.15 to 5.45 +/- 1.68 pg/ml; P less than 0.005) characterized the humoral activity of enalapril maleate. Moreover, a significant decrease of plasma norepinephrine levels was observed during the follow-up period with maximal reduction on the 120th day (from 311 +/- 34 to 197 +/- 33 pg/ml; P less than 0.01). It has been demonstrated that the pressor effect of angiotensin II was blunted during exercise. Our hemodynamic and humoral results appear to confirm the hypothesis that

  9. Effects of aqueous extract of Hibiscus sabdariffa on the renin-angiotensin-aldosterone system of Nigerians with mild to moderate essential hypertension: A comparative study with lisinopril.

    Science.gov (United States)

    Nwachukwu, Daniel Chukwu; Aneke, Eddy Ikemefuna; Obika, Leonard Fidelis; Nwachukwu, Nkiru Zuada

    2015-01-01

    The present study investigated the effects of aqueous extract of Hibiscus sabdariffa (HS) on the three basic components of renin-angiotensin-aldosterone system: Plasma renin, serum angiotensin-converting enzyme (ACE), and plasma aldosterone (PA) in mild to moderate essential hypertensive Nigerians and compared with that of lisinopril, an ACE inhibitor. A double-blind controlled randomized clinical study was used. Seventy-eight newly diagnosed but untreated mild to moderate hypertensive subjects attending Medical Outpatients Clinic of Enugu State University Teaching Hospital, Enugu were recruited for the study. Those in Group A received placebo (150 mg/kg/day), Group B were given lisinopril (10 mg once daily) while those in Group C received aqueous extract of HS (150 mg/kg/day). After 4 weeks of treatment, the levels of plasma renin, serum ACE, and PA were determined. HS and lisinopril significantly (P < 0.001) reduced PA compared to placebo by 32.06% and 30.01%, respectively. Their effects on serum ACE and plasma renin activity (PRA) were not significant compared to placebo; they reduced ACE by 6.63% and 5.67% but increased plasma PRA by 2.77% and 5.36%, respectively. HS reduced serum ACE and PA in mild to moderate hypertensive Nigerians with equal efficacy as lisinopril. These actions are possibly due to the presence of anthocyanins in the extract.

  10. The renin–angiotensin–aldosterone system blockade in patients with advanced diabetic kidney disease

    Directory of Open Access Journals (Sweden)

    Sheila Bermejo

    2018-03-01

    Full Text Available Background and objectives: Diabetic kidney disease is the leading cause of end-stage chronic kidney disease (CKD. The renin–angiotensin–aldosterone system (RAAS blockade has been shown to slow the progression of diabetic kidney disease. Our objectives were: to study the percentage of patients with diabetic kidney disease treated with RAAS blockade, to determine its renal function, safety profile and assess whether its administration is associated with increased progression of CKD after 3 years of follow-up. Materials and methods: Retrospective study. 197 diabetic kidney disease patients were included and divided into three groups according to the treatment: patients who had never received RAAS blockade (non-RAAS blockade, patients who at some point had received RAAS blockade (inconstant-RAAS blockade and patients who received RAAS blockade (constant-RAAS blockade. Clinical characteristics and analytical variables such as renal function, electrolytes, glycosylated hemoglobin and glomerular filtration rate according to CKD-EPI and MDRD formulas were assessed. We also studied their clinical course (baseline, 1 and 3 years follow-up in terms of treatment group, survival, risk factors and renal prognosis. Results: Non-RAAS blockade patients had worse renal function and older age (p < 0.05 at baseline compared to RAAS blockade patients. Patients who received RAAS blockade were not found to have greater toxicity or chronic kidney disease progression and no differences in renal prognosis were identified. Mortality was higher in non-RAAS blockade patients, older patients and patients with worse renal function (p < 0.05. In the multivariate analysis, older age and worse renal function were risk factors for mortality. Conclusions: Treatment with RAAS blockade is more common in diabetic kidney disease patients with eGFR ≥ 30 ml/min/1.73 m2. In our study, there were no differences in the evolution of renal function

  11. Human in vivo study of the renin-angiotensin-aldosterone system and the sympathetic activity after 8 weeks daily intake of fermented milk.

    Science.gov (United States)

    Usinger, Lotte; Ibsen, Hans; Linneberg, Allan; Azizi, Michel; Flambard, Bénédicte; Jensen, Lars T

    2010-03-01

    Milk fermented by lactic acid bacteria is suggested to have antihypertensive effect in humans. In vitro and animal studies have established an angiotensin-converting enzyme (ACE) inhibitor effect of peptides in fermented milk. However, other modes of action must be considered, because until today no human studies have confirmed an ACE inhibition in relation to the intake of fermented milk. We undertook a double-blinded randomized placebo-controlled study including 94 borderline-hypertensive persons to study the effect on human physiology of Lactobacillus helveticus fermented milk. The subjects were randomized into three groups: Cardi04-300 ml, Cardi04-150 ml or placebo. All components of the renin-angiotensin-aldosterone system were measured several times. Sympathetic activity was estimated by plasma noradrenaline and cardiovascular response to head-up tilt at baseline and after 8 weeks of intervention. No ACE inhibition of the fermented milk was demonstrated, as none of the components of the renin-angiotensin-aldosteron system changed. Plasma noradrenaline response to tilt test after intervention stayed unchanged between groups (P = 0.38), but declined in the group Cardi04-300 from 2.01 +/- 0.93 nmol l(-1) at baseline to 1.49 +/- 0.74 nmol l(-1) after 8 weeks (P = 0.002). There was no change in 24-h ambulatory blood pressure or heart rate between groups. Despite a known ACE inhibitory effect in vitro and in animals, milk fermented with Lb. helveticus did not inhibit ACE in humans. Our results suggest that the intake of fermented milk decreases sympathetic activity, although not to an extent mediating reductions of blood pressure and heart rate in borderline-hypertensive subjects.

  12. Aldosterone synthase C-344T, angiotensin II type 1 receptor ...

    Indian Academy of Sciences (India)

    2014-12-26

    Dec 26, 2014 ... RESEARCH ARTICLE. Aldosterone synthase C-344T, angiotensin II type 1 receptor A1166C and 11-β hydroxysteroid dehydrogenase G534A gene polymorphisms and essential hypertension in the population of Odisha, India. MANISHA PATNAIK1,5, PALLABI PATI1, SURENDRA N. SWAIN2, MANOJ K.

  13. Aldosterone synthase C-344T, angiotensin II type 1 receptor ...

    Indian Academy of Sciences (India)

    This study was undertaken to investigate the association of aldosterone synthase C-344T, angiotensin II type I receptor A1166C and 11- hydroxysteroid dehydrogenase type 2 G534A polymorphisms with essential hypertension in the population of Odisha, India. A total of 246 hypertensive subjects (males, 159; females, ...

  14. Renin-angiotensin-aldosterone genotype influences ventricular remodeling in infants with single ventricle.

    Science.gov (United States)

    Mital, Seema; Chung, Wendy K; Colan, Steven D; Sleeper, Lynn A; Manlhiot, Cedric; Arrington, Cammon B; Cnota, James F; Graham, Eric M; Mitchell, Michael E; Goldmuntz, Elizabeth; Li, Jennifer S; Levine, Jami C; Lee, Teresa M; Margossian, Renee; Hsu, Daphne T

    2011-05-31

    We investigated the effect of polymorphisms in the renin-angiotensin-aldosterone system (RAAS) genes on ventricular remodeling, growth, renal function, and response to enalapril in infants with single ventricle. Single ventricle infants enrolled in a randomized trial of enalapril were genotyped for polymorphisms in 5 genes: angiotensinogen, angiotensin-converting enzyme, angiotensin II type 1 receptor, aldosterone synthase, and chymase. Alleles associated with renin-angiotensin-aldosterone system upregulation were classified as risk alleles. Ventricular mass, volume, somatic growth, renal function using estimated glomerular filtration rate, and response to enalapril were compared between patients with ≥2 homozygous risk genotypes (high risk), and those with SCPC) and at age 14 months. Of 230 trial subjects, 154 were genotyped: Thirty-eight were high risk, and 116 were low risk. Ventricular mass and volume were elevated in both groups pre-SCPC. Ventricular mass and volume decreased and estimated glomerular filtration rate increased after SCPC in the low-risk (PSCPC surgery, less improvement in renal function, and impaired somatic growth, the latter especially in patients receiving enalapril. Renin-angiotensin-aldosterone system genotype may identify a high-risk subgroup of single ventricle patients who fail to fully benefit from volume-unloading surgery. Follow-up is warranted to assess long-term impact. http://www.clinicaltrials.gov. Unique identifier: NCT00113087.

  15. Relationship Between Aldosterone and Parathyroid Hormone, and the Effect of Angiotensin and Aldosterone Inhibition on Bone Health

    DEFF Research Database (Denmark)

    L.S., Bislev; T., Sikjaer; L., Rolighed

    2015-01-01

    Emerging evidence suggests a stimulating effect of parathyroid hormone (PTH) on the reninnullangiotensinnullaldosterone system (RAAS). In primary hyperparathyroidism, chronic-elevated PTH levels seem to stimulate the RAAS which may explain the increased risk of cardiovascular disease (CVD......). In addition to increased PTH levels, low vitamin D levels may also directly increase risk of CVD, as vitamin D, itself, has been shown to inhibit the RAAS. Angiotensin II, aldosterone and cortisol all negatively impact bone health. Hyperaldosteronism is associated with a reversible secondary...... hyperparathyroidism due to increased renal calcium excretion. Moreover, the angiotensin II receptor is expressed by human parathyroid tissue, and angiotensin may therefore directly stimulates PTH secretion. An increased bone loss is found in patients with hyperaldosteronism. The angiotensin II receptor seems main...

  16. Renin-angiotensin-aldosterone system blockers for heart failure with reduced ejection fraction or left ventricular dysfunction: Network meta-analysis.

    Science.gov (United States)

    Xie, Wuxiang; Zheng, Fanfan; Song, Xiaoyu; Zhong, Baoliang; Yan, Li

    2016-02-15

    Renin-angiotensin-aldosterone system (RAAS) blockers are effective therapies for heart failure and reduced ejection fraction (HFrEF) or left ventricular dysfunction (LVD). We aimed to assess the efficacy and safety of RAAS blockers in these patients. We searched MEDLINE, EMBASE, and Cochrane Library in May 2015. Twenty-one double-blind randomized controlled trials (RCTs) with 69,229 patients were included this network meta-analysis. Compared with placebo, an angiotensin receptor-neprilysin inhibitor (ARNI) had the highest probability of reducing all-cause mortality (odds ratio [OR]=0.67, 95% credible interval [CrI]: 0.48-0.86), followed by an aldosterone receptor antagonist (ARA, OR=0.74, 95% CrI: 0.62-0.88) and an angiotensin-converting enzyme inhibitor (ACEI, OR=0.80, 95% CrI: 0.71-0.89). The most efficacious therapy for preventing heart failure hospitalization was ARNI (OR=0.55, 95% CrI: 0.40-0.71), followed by combination therapy with an angiotensin II receptor blocker (ARB) plus an ACEI (OR=0.61, 95% CrI: 0.49-0.75), then an ACEI alone (OR=0.69, 95% CrI: 0.61-0.77). Sensitivity analysis restricted to nine RCTs with a high background use of ACEI and/or ARB (>80%) indicated that adding an ARA to current standard therapy significantly reduced mortality (OR=0.73, 95% CrI: 0.51-0.95) and hospitalization risk (OR=0.67, 95% CrI: 0.47-0.87), but did not significantly increase the discontinuation risk (OR=1.29, 95% CrI: 0.83-2.31). ARNI has the highest probability of being the most efficacious therapy for HFrEF in reducing death and hospitalization for heart failure. ARA has the most favorable benefit-risk profile as an adjunct to background ACEI and/or ARB therapy. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. Orthostatic effects of midodrine versus L-NAME on cerebral blood flow and the renin-angiotensin-aldosterone system in tetraplegia.

    Science.gov (United States)

    Wecht, Jill M; Radulovic, Miroslav; Rosado-Rivera, Dwindally; Zhang, Run-Lin; LaFountaine, Michael F; Bauman, William A

    2011-11-01

    To compare responses to head-up tilt (HUT) in individuals with chronic tetraplegia after midodrine hydrochloride (10 mg) versus nitro-L-arginine methyl ester (L-NAME, 1 mg/kg) administration. Prospective comparative drug trial. Veterans Affairs medical center. Participants (N=7) were studied during 3 laboratory visits: no drug, midodrine (administered orally 30 min before HUT), and L-NAME (infused over a 60-min period). Anti-hypotensive agents, midodrine, and L-NAME. Mean arterial pressure (MAP), cerebral blood flow (CBF), and markers of the renin-angiotensin-aldosterone system (RAAS, plasma renin and serum aldosterone) were measured in the supine position at baseline (BL) and during a 45° HUT maneuver. Data were compared between BL and the average of 3 assessments collected during HUT. Orthostatic MAP and CBF were increased with the midodrine and L-NAME groups compared with the no drug trial and the relationship between the change in MAP and CBF was significant (r=0.770; Pmidodrine appeared to suppress the post-HUT RAAS response compared with no drug. Increasing orthostatic blood pressure with L-NAME or midodrine appears to increase CBF and suppress the RAAS during HUT in persons with tetraplegia, although more data are needed to confirm these preliminary findings. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  18. Effect of exercise training on the renin-angiotensin-aldosterone system in healthy individuals: a systematic review and meta-analysis.

    Science.gov (United States)

    Goessler, Karla; Polito, Marcos; Cornelissen, Véronique Ann

    2016-03-01

    The aim of this systematic review and meta-analysis was to evaluate the effect of exercise training on parameters of the renin-angiotensin-aldosterone system (RAAS) in healthy adults, and to investigate the relation with training induced changes in blood pressure. A systematic search was conducted and we included randomized controlled trials lasting ⩾4 weeks investigating the effects of exercise on parameters of the RAAS in healthy adults (age ⩾18 years) and published in a peer-reviewed journal up to December 2013. Fixed effects models were used and data are reported as weighted means and 95% confidence limits (CL). Eleven randomized controlled trials with a total of 375 individuals were included. Plasma renin activity was reduced after exercise training (n= 7 trials, standardized mean difference -0.25 (95% CL -0.5 to -0.001), P=0.049), whereas no effect was observed on serum aldosterone ((n= 3 trials; standardized mean difference -0.79 (-1.97 to +0.39)) or angiotensin II (n=3 trials; standardized mean difference -0.16 (-0.61 to +0.30). Significant reductions in systolic blood pressure -5.65 mm Hg (-8.12 to -3.17) and diastolic blood pressure -3.64 mm Hg (-5.4 to -1.91) following exercise training were observed. No relation was found between net changes in plasma renin activity and net changes in blood pressure (P>0.05). To conclude, although we observed a significant reduction in plasma renin activity following exercise training this was not related to the observed blood pressure reduction. Given the small number of studies and small sample sizes, larger well-controlled randomized studies are required to confirm our results and to investigate the potential role of the RAAS in the observed improvements in blood pressure following exercise training.

  19. In Vitro Regulation of Enzymes of the Renin-angiotensin-aldosterone System by Isoquercitrin, Phloridzin and their Long Chain Fatty Acid Derivatives

    Directory of Open Access Journals (Sweden)

    Khushwant S. Bhullar

    2014-05-01

    Full Text Available Background: Hypertension is a crucial risk factor for development of cardiovascular and neurological diseases. Flavonoids exhibit a wide range of biological effects and have had increased interest as a dietary approach for the prevention or possible treatment of hypertension. However, continuous efforts have been made to structurally modify natural flavonoids with the hope of improving their biological activities. One of the methods used for the possible enhancement of flavonoid efficacy is enzymatic esterification of flavonoids with fatty acids. Objective: The current study is designed to investigate the antihypertensive activity of isoquercitrin (quercetin-3-O-glucoside, Q3G and phloridzin (PZ in comparison to their twelve long chain fatty acid derivatives via enzymatic inhibition of renin angiotensin aldosterone system (RAAS enzymes. Methods: The novel flavonoid esters were synthesized by the acylation of isoquercitrin and phloridzin with long chain unsaturated and saturated fatty acids (C18–C22. These acylated products were then tested for their in vitro angiotensin converting enzyme (ACE, renin and aldosterone synthase activities. Results: The linoleic and α-linolenic acid esters of PZ were the strongest (IC50 69.9-70.9 µM while Q3G and PZ (IC50 >200 µM were the weakest renin inhibitors in vitro (p≤0.05. The eicosapentaenoic acid ester of PZ (IC50 16.0 µM was the strongest inhibitor of ACE, while PZ (IC50 124.0 µM was the weakest inhibitor (p≤0.05 among all tested compounds. However, all investigated compounds had low (5.0-11.9% or no effect on aldosterone synthase inhibition (p≤0.05. The parent compound Q3G and the eicosapentaenoic acid ester of PZ emerged as the strongest ACE inhibitors. Conclusions: The structural modification of Q3G and PZ significantly improved their antihypertensive activities. The potential use of PZ derivatives as natural health products to treat hypertension needs to be further evaluated

  20. Changes in the renin-angiotensin-aldosterone system in response to dietary salt intake in normal and hypertensive pregnancy. A randomized trial

    DEFF Research Database (Denmark)

    Nielsen, Lise H; Ovesen, Per; Hansen, Mie R

    2016-01-01

    during low-salt diet in PE patients (n = 7), healthy pregnant women (n = 15), and nonpregnant women (n = 13). High-salt intake decreased renin and angiotensin II concentrations significantly in healthy pregnant women (P ... in aldosterone and increases in brain natriuretic peptid (BNP) were similar in the groups. In PE patients, uterine and umbilical artery indices were not adversely changed during low-salt diet. Creatinine clearance was significantly lower in PE with no change by salt intake. PE patients displayed alterations...... of plasma renin and angiotensin II in response to changes in dietary salt intake compatible with a primary increase in renal sodium reabsorption in hypertensive pregnancies....

  1. Myeloperoxidase, asymmetric dimethyl-arginine and the renin-angiotensin-aldosterone-system in cardiovascular risk patients: Cross-sectional findings from the Ludwigshafen Risk and Cardiovascular Health (LURIC) study.

    Science.gov (United States)

    Zelzer, Sieglinde; Enko, Dietmar; Pilz, Stefan; Tomaschitz, Andreas; März, Winfried; Meinitzer, Andreas

    2017-09-01

    The leukocyte-derived myeloperoxidase (MPO), the nitric oxidase synthase (NOS) inhibitor asymmetrical dimethyl-arginine (ADMA) and the renin-angiotensin-aldosterone-system (RAAS) are associated with cardiovascular diseases (CVD). This study aimed to investigate potential interactions between the RAAS, ADMA and MPO in cardiovascular risk patients. All in all, 1446 patients, who were referred to coronary angiography, were included in this prospective study. MPO, ADMA and circulating serum markers of the RAAS system were measured. Additionally, all-cause and CVD mortality, cardiovascular risk factors, inflammatory and endothelial markers, and medication use were investigated. MPO concentrations were significantly associated with ADMA (P=0.002), renin (P=0.001) and angiotensin II levels (P=0.015), whereas ADMA was in tendency associated with renin (P=0.059) and significantly with angiotensin II (P=0.001). Both, ADMA and MPO were inversely correlated with angiotensinogen, angiotensin I and the angiotensin I/angiotensin II ratio. ADMA and angiotensin II were found stronger independent risk factors for all-cause and CVD mortality compared to MPO. MPO concentrations were significantly associated with higher ADMA levels and an up-regulated circulating RAAS in patients with CVD. Moreover, serum levels of ADMA and angiotensin II were shown to be more predictive for all-cause and CVD mortality compared to MPO. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  2. MITOCHONDRIAL REACTIVE OXYGEN SPECIES (ROS AS SIGNALLING MOLECULES OF INTRACELLULAR PATHWAYS TRIGGERED BY THE CARDIAC RENIN-ANGIOTENSIN II-ALDOSTERONE SYSTEM (RAAS.

    Directory of Open Access Journals (Sweden)

    Verónica Celeste De Giusti

    2013-05-01

    Full Text Available Mitochondria represent major sources of basal reactive oxygen species (ROS production of the cardiomyocyte. The role of ROS as signalling molecules that mediate different intracellular pathways has gained increasing interest among physiologists in the last years. In our lab, we have been studying the participation of mitochondrial ROS in the intracellular pathways triggered by the renin-angiotensin II-aldosterone system (RAAS in the myocardium during the past few years. We have demonstrated that acute activation of cardiac RAAS induces mitochondrial ATP-dependent potassium channel (mitoKATP opening with the consequent enhanced production of mitochondrial ROS. These oxidant molecules, in turn, activate membrane transporters, as sodium/hydrogen exchanger (NHE-1 and sodium/bicarbonate cotransporter (NBC via the stimulation of the ROS-sensitive MAPK cascade. The stimulation of such effectors leads to an increase in cardiac contractility. In addition, it is feasible to suggest that a sustained enhanced production of mitochondrial ROS induced by chronic cardiac RAAS, and hence, chronic NHE-1 and NBC stimulation, would also result in the development of cardiac hypertrophy.

  3. Prognostic Impact of Loop Diuretics in Patients With Chronic Heart Failure - Effects of Addition of Renin-Angiotensin-Aldosterone System Inhibitors and β-Blockers.

    Science.gov (United States)

    Miura, Masanobu; Sugimura, Koichiro; Sakata, Yasuhiko; Miyata, Satoshi; Tadaki, Soichiro; Yamauchi, Takeshi; Onose, Takeo; Tsuji, Kanako; Abe, Ruri; Oikawa, Takuya; Kasahara, Shintaro; Nochioka, Kotaro; Takahashi, Jun; Shimokawa, Hiroaki

    2016-05-25

    It remains to be elucidated whether addition of renin-angiotensin-aldosterone system (RAAS) inhibitors and/or β-blockers to loop diuretics has a beneficial prognostic impact on chronic heart failure (CHF) patients. From the Chronic Heart failure Analysis and Registry in the Tohoku district 2 (CHART-2) Study (n=10,219), we enrolled 4,134 consecutive patients with symptomatic stage C/D CHF (mean age, 69.3 years, 67.7% male). We constructed Cox models for composite of death, myocardial infarction, stroke and HF admission. On multivariate inverse probability of treatment weighted (IPTW) Cox modeling, loop diuretics use was associated with worse prognosis with hazard ratio (HR) 1.28 (Pdiuretics were associated with worse prognosis with HR 1.32 and 1.56, respectively (both Pdiuretics. Chronic use of loop diuretics is significantly associated with worse prognosis in CHF patients in a dose-dependent manner, whereas the triple combination of RAAS inhibitor(s), MRA, and β-blocker(s) is associated with better prognosis when combined with low-dose loop diuretics. (Circ J 2016; 80: 1396-1403).

  4. Association between renin-angiotensin-aldosterone system blockade and future osteoporotic fracture risk in hypertensive population: A population-based cohort study in Taiwan.

    Science.gov (United States)

    Chen, Chang-I; Yeh, Jong-Shiuan; Tsao, Nai-Wen; Lin, Fen-Yen; Shih, Chun-Ming; Chiang, Kuang-Hsing; Kao, Yung-Ta; Fang, Yu-Ann; Tsai, Lung-Wen; Liu, Wen-Chi; Nakagami, Hironori; Morishita, Ryuichi; Kuo, Yi-Jie; Huang, Chun-Yao

    2017-11-01

    Tissue renin-angiotensin-aldosterone system (RAAS) activation in sites of osteoporosis had been demonstrated in animal studies; however, the possibility of RAAS blockade to prevent future osteoporotic fracture had rarely been verified in clinical studies. We Used the Taiwan Longitudinal Health insurance database 2000 to 2008, the cohort study comprised patients age over 40 with a recorded new diagnosis of hypertension between January 1, 2000 to December 31, 2008, in addition, patients who had diagnosis of osteoporosis before the date of cohort enter were excluded. After the definite diagnosis of hypertension, each patient was followed until osteoporotic fracture happened or the end of 2008. The occurrence of osteoporotic fracture was evaluated in patients who either were or without taking RAAS blockade agents. Cox proportional hazard regressions were used to evaluate the osteoporotic fracture incidence after adjusting for known confounding factors. In total, 57,132 hypertensive patients comprised the study cohort. Our study results showed that the incidence of osteoporosis fracture in the whole cohort was significantly higher in the RAAS blockade non-user group than the user group. This phenomenon was observed in both sex and all age categories. Sensitivity analysis further showed the concordant lower osteoporosis fracture risk in patients with various RAAS blockers usage durations; the risk of osteoporosis fracture was the lowest in those drug use >365 days when compared with the non-user cohort. In conclusion, our study result demonstrated the lower future osteoporotic fracture risk in hypertensive subjects who received long term RAAS blocker treatment.

  5. Effects of Dietary Sodium Restriction in Kidney Transplant Recipients Treated With Renin-Angiotensin-Aldosterone System Blockade: A Randomized Clinical Trial.

    Science.gov (United States)

    de Vries, Laura V; Dobrowolski, Linn C; van den Bosch, Jacqueline J O N; Riphagen, Ineke J; Krediet, C T Paul; Bemelman, Frederike J; Bakker, Stephan J L; Navis, Gerjan

    2016-06-01

    In patients with chronic kidney disease receiving renin-angiotensin-aldosterone system (RAAS) blockade, dietary sodium restriction is an often-used treatment strategy to reduce blood pressure (BP) and albuminuria. Whether these effects extend to kidney transplant recipients is unknown. We therefore studied the effects of dietary sodium restriction on BP and urinary albumin excretion (UAE) in kidney transplant recipients receiving RAAS blockade. Two-center randomized crossover trial. Stable outpatient kidney transplant recipients with creatinine clearance > 30mL/min, BP ≥120/80mmHg, receiving stable RAAS blockade therapy. 6-week regular-sodium diet (target, 150mmol/24 h) and a 6-week low-sodium diet (target, 50mmol/24 h). Main outcome parameters were systolic and diastolic BP, UAE, and estimated glomerular filtration rate (eGFR) at the end of each diet period. Dietary adherence was assessed by 24-hour urinary sodium excretion. We randomly assigned 23 kidney transplant recipients, of whom 22 (mean age, 58±8 [SD] years; 50% men; mean eGFR, 51±21mL/min/1.73m(2)) completed the study. One patient withdrew from the study because of concerns regarding orthostatic hypotension on the low-sodium diet. Sodium excretion decreased from 164±50mmol/24 h during the regular-sodium diet to 87±55mmol/24 h during the low-sodium diet (mean difference, -77 [95% CI, -110 to -44] mmol/24 h; Padherence to sodium diet was achieved in 86% of patients. In stable kidney transplant recipients receiving RAAS blockade, dietary sodium restriction effectively reduces BP without affecting eGFR. Dietary sodium restriction is relevant to BP management in kidney transplant recipients receiving RAAS blockade. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  6. Individual variability in response to renin angiotensin aldosterone system inhibition predicts cardiovascular outcome in patients with type 2 diabetes: A primary care cohort study.

    Science.gov (United States)

    Apperloo, Ellen M; Pena, Michelle J; de Zeeuw, Dick; Denig, Petra; Heerspink, Hiddo J L

    2018-01-18

    To assess variability in systolic blood pressure (SBP) and albuminuria (urinary albumin creatinine ratio [UACR]) responses in patients with type 2 diabetes mellitus initiating renin angiotensin aldosterone system (RAAS) inhibition, and to assess the association of response variability with cardiovascular outcomes. We performed an observational cohort study in patients with type 2 diabetes who started RAAS inhibition between 2007 and 2013 (n = 1600). Patients were identified from general practices in the Netherlands. Individual response in SBP and UACR was assessed during 15 months' follow-up. Patients were categorized as: good responders (∆SBP 0% or ∆SBP >0 mm Hg and ∆UACR 0 mm Hg and ∆UACR >0%). Multivariable Cox regression was performed to test the association between initial RAAS inhibition response and subsequent cardiovascular outcomes. After starting RAAS inhibition, the mean SBP change was -13.2 mm Hg and the median UACR was -36.6%, with large between-individual variability, both in SBP [5th to 95th percentile: 48.5-20] and UACR [5th to 95th percentile: -87.6 to 171.4]. In all, 812 patients (51%) were good responders, 353 (22%) had a good SBP but poor UACR response, 268 (17%) had a good UACR but poor SBP response, and 167 patients (10%) were poor responders. Good responders had a lower risk of cardiovascular events than poor responders (hazard ratio 0.51, 95% confidence interval 0.30-0.86; P = .012). SBP and UACR response after RAAS inhibition initiation varied between and within individual patients with type 2 diabetes treated in primary care. Poor responders had the highest risk of cardiovascular events, therefore, more efforts are needed to develop personalized treatment plans for these patients. © 2018 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.

  7. Renin-angiotensin-aldosterone responsiveness to low sodium and blood pressure reactivity to angiotensin-II are unrelated to cholesteryl ester transfer protein mass in healthy subjects

    NARCIS (Netherlands)

    Krikken, Jan A.; Dallinga-Thie, Geesje M.; Navis, Gerjan; Dullaart, Robin P. F.

    2008-01-01

    BACKGROUND: The blood pressure increase associated with the cholesteryl ester transfer protein (CETP) inhibitor, torcetrapib is probably attributable to an off-target effect but it is unknown whether activation of the renin-angiotensin-aldosterone system (RAAS) may be related to variation in the

  8. Progression of Renal Insufficiency in Patients with Essential Hypertension Treated with Renin Angiotensin Aldosterone System Blockers: An Electrocardiographic Correlation

    Directory of Open Access Journals (Sweden)

    Luis Rodriguez-Padial

    2017-12-01

    Full Text Available Background: There is a frequent association between renal insufficiency and cardiovascular disease in patients with essential hypertension (HTN. The aim of this study was to analyze the relationship between ECG parameters and the progress of renal damage in patients with treated HTN. Methods: 109 patients with HTN had their microalbuminuria monitored over a 3-year time frame. During the last 3 months of follow-up, an ECG was recorded. Patients were divided into 3 groups according to the deterioration of their renal function: normoalbuminuria during the study period (normo–normo; n = 51; normoalbuminuria developing microalbuminuria (normo–micro; n = 29; and microalbuminuria at baseline (micro–micro; n = 29. Results: There were no differences in presence of left ventricular hypertrophy between the 3 groups. RV6/RV5 >1 was observed more frequently as renal function declined (p = 0.025. The 12-lead QRS-complex voltage-duration product was significantly increased in patients without microalbuminuria at baseline who went on to develop microalbuminuria (p = 0.006. Patients who developed microalbuminuria during follow-up, with positive Cornell voltage criteria, showed a lesser degree of progression of microalbuminuria when compared with the rest of the subgroups (p = 0.044. Furthermore, patients with microalbuminuria at baseline treated with angiotensin receptor blockers and diuretics, and positive Cornell voltage criteria, showed a higher degree of microalbuminuria compared to those with negative Cornell voltage criteria (p = 0.016. Conclusions: In patients with HTN, we identified some ECG parameters, which predict renal disease progression in patients with HTN, which may permit the identification of patients who are at risk of renal disease progression, despite optimal antihypertensive pharmacotherapy.

  9. New perspectives in the renin-angiotensin-aldosterone system (RAAS III: endogenous inhibition of angiotensin converting enzyme (ACE provides protection against cardiovascular diseases.

    Directory of Open Access Journals (Sweden)

    Miklós Fagyas

    Full Text Available ACE inhibitor drugs decrease mortality by up to one-fifth in cardiovascular patients. Surprisingly, there are reports dating back to 1979 suggesting the existence of endogenous ACE inhibitors. Here we investigated the clinical significance of this potential endogenous ACE inhibition. ACE concentration and activity was measured in patient's serum samples (n = 151. ACE concentration was found to be in a wide range (47-288 ng/mL. ACE activity decreased with the increasing concentration of the serum albumin (HSA: ACE activity was 56 ± 1 U/L in the presence of 2.4 ± 0.3 mg/mL HSA, compared to 39 ± 1 U/L in the presence of 12 ± 1 mg/mL HSA (values are mean ± SEM. Effects of the differences in ACE concentration were suppressed in human sera: patients with ACE DD genotype exhibited a 64% higher serum ACE concentration (range, 74-288 ng/mL, median, 155.2 ng/mL, n = 52 compared to patients with II genotype (range, 47-194 ng/mL, median, 94.5 ng/mL, n = 28 while the difference in ACE activities was only 32% (range, 27.3-59.8 U/L, median, 43.11 U/L, and range 15.6-55.4 U/L, median, 32.74 U/L, respectively in the presence of 12 ± 1 mg/mL HSA. No correlations were found between serum ACE concentration (or genotype and cardiovascular diseases, in accordance with the proposed suppressed physiological ACE activities by HSA (concentration in the sera of these patients: 48.5 ± 0.5 mg/mL or other endogenous inhibitors. Main implications are that (1 physiological ACE activity can be stabilized at a low level by endogenous ACE inhibitors, such as HSA; (2 angiotensin II elimination may have a significant role in angiotensin II related pathologies.

  10. Proteomic prediction and Renin angiotensin aldosterone system Inhibition prevention Of early diabetic nephRopathy in TYpe 2 diabetic patients with normoalbuminuria (PRIORITY)

    DEFF Research Database (Denmark)

    Lindhardt, Morten; Persson, Frederik; Currie, Gemma

    2016-01-01

    INTRODUCTION: Diabetes mellitus affects 9% of the European population and accounts for 15% of healthcare expenditure, in particular, due to excess costs related to complications. Clinical trials aiming for earlier prevention of diabetic nephropathy by renin angiotensin system blocking treatment...

  11. Aldosterone and angiotensin II induced protein aggregation in renal proximal tubules

    DEFF Research Database (Denmark)

    Cheema, Muhammad Umar; Poulsen, Ebbe Toftgaard; Enghild, Jan J

    2013-01-01

    systems in the kidney from control rats and rats receiving aldosterone or angiotensin II treatment for 7 days. Control rats formed both aggresomes and autophagosomes specifically in the proximal tubules, indicating a need for these structures even under baseline conditions. Fluorescence sorted aggresomes......Renal tubules are highly active transporting epithelia and are at risk of protein aggregation due to high protein turnover and/or oxidative stress. We hypothesized that the risk of aggregation was increased upon hormone stimulation and assessed the state of the intracellular protein degradation...... contained various rat keratins known to be expressed in renal tubules as assessed by protein mass spectrometry. Aldosterone administration increased the abundance of the proximal tubular aggresomal protein keratin 5, the ribosomal protein RPL27, ataxin-3, and the chaperone heat shock protein 70...

  12. Effect of Losartan on Right Ventricular Dysfunction: Results From the Double-Blind, Randomized REDEFINE Trial (Right Ventricular Dysfunction in Tetralogy of Fallot: Inhibition of the Renin-Angiotensin-Aldosterone System) in Adults With Repaired Tetralogy of Fallot.

    Science.gov (United States)

    Bokma, Jouke P; Winter, Michiel M; van Dijk, Arie P; Vliegen, Hubert W; van Melle, Joost P; Meijboom, Folkert J; Post, Martijn C; Berbee, Jacqueline K; Boekholdt, S Matthijs; Groenink, Maarten; Zwinderman, Aeilko H; Mulder, Barbara J M; Bouma, Berto J

    2018-04-03

    The effect of angiotensin II receptor blockers on right ventricular (RV) function is still unknown. Angiotensin II receptor blockers are beneficial in patients with acquired left ventricular dysfunction, and recent findings have suggested a favorable effect in symptomatic patients with systemic RV dysfunction. The current study aimed to determine the effect of losartan, an angiotensin II receptor blocker, on subpulmonary RV dysfunction in adults after repaired tetralogy of Fallot. The REDEFINE trial (Right Ventricular Dysfunction in Tetralogy of Fallot: Inhibition of the Renin-Angiotensin-Aldosterone System) is an investigator-initiated, multicenter, prospective, 1:1 randomized, double-blind, placebo-controlled study. Adults with repaired tetralogy of Fallot and RV dysfunction (RV ejection fraction [EF] 0.30 for all). In predefined subgroup analyses, losartan did not have a statistically significant impact on RV EF in subgroups with symptoms, restrictive RV, RV EFtetralogy of Fallot. Future larger studies may determine whether there might be a role for losartan in specific vulnerable subgroups. URL: https://www.clinicaltrials.gov. Unique identifier: NCT02010905. © 2017 American Heart Association, Inc.

  13. Aldosterone and angiotensin II induce protein aggregation in renal proximal tubules.

    Science.gov (United States)

    Cheema, Muhammad U; Poulsen, Ebbe T; Enghild, Jan J; Hoorn, Ewout J; Hoorn, Ewout; Fenton, Robert A; Praetorius, Jeppe

    2013-09-01

    Renal tubules are highly active transporting epithelia and are at risk of protein aggregation due to high protein turnover and/or oxidative stress. We hypothesized that the risk of aggregation was increased upon hormone stimulation and assessed the state of the intracellular protein degradation systems in the kidney from control rats and rats receiving aldosterone or angiotensin II treatment for 7 days. Control rats formed both aggresomes and autophagosomes specifically in the proximal tubules, indicating a need for these structures even under baseline conditions. Fluorescence sorted aggresomes contained various rat keratins known to be expressed in renal tubules as assessed by protein mass spectrometry. Aldosterone administration increased the abundance of the proximal tubular aggresomal protein keratin 5, the ribosomal protein RPL27, ataxin-3, and the chaperone heat shock protein 70-4 with no apparent change in the aggresome-autophagosome markers. Angiotensin II induced aggregation of RPL27 specifically in proximal tubules, again without apparent change in antiaggregating proteins or the aggresome-autophagosome markers. Albumin endocytosis was unaffected by the hormone administration. Taken together, we find that the renal proximal tubules display aggresome formation and autophagy. Despite an increase in aggregation-prone protein load in these tubules during hormone treatment, renal proximal tubules seem to have sufficient capacity for removing protein aggregates from the cells.

  14. Advances in understanding the renin-angiotensin-aldosterone system (RAAS in blood pressure control and recent pivotal trials of RAAS blockade in heart failure and diabetic nephropathy [version 1; referees: 3 approved

    Directory of Open Access Journals (Sweden)

    Lama Ghazi

    2017-03-01

    Full Text Available The renin-angiotensin-aldosterone system (RAAS plays a fundamental role in the physiology of blood pressure control and the pathophysiology of hypertension (HTN with effects on vascular tone, sodium retention, oxidative stress, fibrosis, sympathetic tone, and inflammation. Fortunately, RAAS blocking agents have been available to treat HTN since the 1970s and newer medications are being developed. In this review, we will (1 examine new anti-hypertensive medications affecting the RAAS, (2 evaluate recent studies that help provide a better understanding of which patients may be more likely to benefit from RAAS blockade, and (3 review three recent pivotal randomized trials that involve newer RAAS blocking agents and inform clinical practice.

  15. Myocardial fibrosis in patients with symptomatic obstructive hypertrophic cardiomyopathy: correlation with echocardiographic measurements, sarcomeric genotypes, and pro-left ventricular hypertrophy polymorphisms involving the renin-angiotensin-aldosterone system.

    Science.gov (United States)

    Blauwet, Lori A; Ackerman, Michael J; Edwards, William D; Riehle, Darren L; Ommen, Steve R

    2009-01-01

    Hypertrophic cardiomyopathy (HCM) is a heterogeneous disorder of the cardiac sarcomere, resulting in myocyte hypertrophy and disarray, interstitial fibrosis, and cardiac dysfunction. Our aim was to determine whether the amount of fibrosis in HCM correlates with echocardiographic measures of diastolic dysfunction, presence of HCM-susceptibility mutations, or polymorphisms in the renin-angiotensin-aldosterone system (RAAS). Surgical specimens from patients with obstructive HCM undergoing septal myectomy at the Mayo Clinic (2001-2004) were examined and compared with autopsy-derived tissues from age- and sex-matched normal controls. Digital image analysis was used to quantitate the fibrosis in representative microscopic sections. Genotyping was performed for myofilament-HCM using polymerase chain reaction, high-performance liquid chromatography, and direct DNA sequencing. RAAS polymorphism status was similarly established. The study included 59 HCM cases and 44 controls. Patients with HCM exhibited more fibrosis (mean 17%, range 3-45%) than controls (mean 8%, range 3-17%) (P or =1 C-encoding allele in CYP11B2-encoded aldosterone synthase. Patients with HCM undergoing septal myectomy had significantly more myocardial interstitial fibrosis than controls. The amount of fibrosis in HCM patients correlated with degree of septal hypertrophy and left ventricular systolic and diastolic function. Notably, neither mutations in cardiac myofilament proteins or polymorphisms in RAAS exhibited strong associations with severity of myocardial fibrosis.

  16. Erratum Aldosterone synthase C-344T, angiotensin II type 1 receptor ...

    Indian Academy of Sciences (India)

    Aldosterone synthase C-344T, angiotensin II type 1 receptor A1166C and 11-β hydroxysteroid dehydrogenase G534A gene polymorphisms and essential hypertension in the population of Odisha, India. Manisha Patnaik, Pallabi Pati, Surendra N. Swain, Manoj K. Mohapatra, Bhagirathi Dwibedi, Shantanu K. Kar.

  17. Aldosterone synthase C-344T, angiotensin II type 1 receptor ...

    Indian Academy of Sciences (India)

    2014-12-26

    Dec 26, 2014 ... lation groups across the globe to establish a genetic basis of the pathogenesis of vascular ... Cholesterol Education Programme (ATP-3) report (2002). ... Statistical analysis. Unpaired t-test / chi-square test / Fisher's tests were used to compare the characteristics of two groups. To compare the aldosterone ...

  18. Oxygen sensitivity of potassium- and angiotensin II-stimulated aldosterone release by bovine adrenal cells.

    Science.gov (United States)

    Brickner, R C; Raff, H

    1991-04-01

    Angiotensin II (AII) and extracellular K+, acting through different intracellular mechanisms, stimulate aldosterone release in a synergistic fashion. We have previously shown that decreases in oxygen (O2) within the physiological range inhibit AII, cyclic AMP (cAMP) and ACTH-stimulated aldosterone release. The present experiment evaluated the effect of various concentrations of O2 on K+-stimulated aldosterone release in the presence and absence of AII. Dispersed bovine adrenal glomerulosa cells were incubated with different concentrations of K+ (0.9-5.4 mmol/l) without and with AII (10 nmol/l) under different concentrations of O2 (0, 5 or 50%); 21% O2 (pO2 = 19.9 +/- 0.5 kPa,n = 9) was used as reference control for comparison. In all cases, increases in K+ stimulated aldosterone release, an effect augmented by AII. Under 0% O2 (pO2 = 8.1 +/- 0.3 kPa, n = 3) and 5% O2 (pO2 = 12.8 +/- 0.5 kPa, n = 3), aldosterone release stimulated by K+ or K+/AII was significantly inhibited compared with that under 21% O2. Conversely, under 50% O2 (pO2 = 36.3 +/- 2.5 kPa, n = 3), aldosterone release stimulated by K+ or K+/AII was significantly augmented. Cortisol secretion was not significantly affected by 5% or 50% O2 but was significantly decreased under 0% O2. The effect of O2 on K+/AII stimulation of aldosterone release, as well as previous experiments with cAMP, progesterone and ACTH, suggest a final common post-receptor oxygen-sensitive component of the aldosterone synthetic pathway. It is suggested that one or more enzymes in the aldosterone synthetic pathway is/are exquisitely sensitive to small changes in O2 within the physiological range.

  19. Human in vivo study of the renin-angiotensin-aldosterone system and the sympathetic activity after 8 weeks daily intake of fermented milk

    DEFF Research Database (Denmark)

    Usinger, Lotte; Ibsen, Hans; Linneberg, Allan

    2010-01-01

    Milk fermented by lactic acid bacteria is suggested to have antihypertensive effect in humans. In vitro and animal studies have established an angiotensin-converting enzyme (ACE) inhibitor effect of peptides in fermented milk. However, other modes of action must be considered, because until today...... no human studies have confirmed an ACE inhibition in relation to the intake of fermented milk....

  20. The efficacy and safety of dual blockage of the renin-angiotensin-aldosterone system in patients with type 2 diabetes, hypertension and obesity without renal dysfunction

    Directory of Open Access Journals (Sweden)

    S A Savelyeva

    2012-09-01

    Full Text Available The purpose of the study was to evaluate the clinical efficacy and safety of dual RAAS blockage during treatment with angiotensin-converting enzyme (ACE inhibitors in combination with a direct renin inhibitor (PIR aliskiren versus combination therapy with ACE inhibitors and angiotensin receptor blocker II (ARB valsartan in patients with type 2 diabetes mellitus (T2DM, arterial hypertension (AH and obesity, without renal dysfunction. Materials and methods. The study included 26 patients with T2DM (10 men and 16 women, mean age 59,0±6,2 years with inadequate control of blood pressure (over 130 and/or 80 mm Hg on prior antihypertensive therapy and without renal dysfunctions (glomerular filtration rate (GFR> 60 ml/min/1, 73 m2 and the of albumin/creatinine (A/C ratio in the morning urine sample <10 mg/mol. After screening with the continuation of the initial therapy, including ACE inhibitors, 14 patients were added aliskiren 150–300 mg/day, 12 patients – valsartan 80–160 mg/day. Evaluation of the treatment effectiveness in terms of blood pressure (mean of three consecutive measurements in the sitting position and the parameters of renal function (serum creatinine and potassium, GFR, A/C ratio in the urine was performed at 4, 12 and 24 weeks of therapy. Results. In the group of patients treated with aliskiren, after 4 weeks of treatment a significant decrease in systolic and diastolic blood pressure (SBP and DBP, respectively was noted as compared to baseline: 146,1 and 138,9 mm Hg, p<0,05, 87,1 and 81,1 mm Hg, p <0,05, respectively; with systolic BP after 24 weeks of treatment decreased to 127,8 (-18,2 mm Hg, p<0,05, diastolic BP to 75,0 (-12, 1 mm Hg, p<0,05, the target blood pressure (≤130/80 mm Hg was achieved in 83% of patients. The group of patients treated with valsartan, after 4 weeks of therapy showed a significant reduction in systolic BP 148 and 141,6 mm Hg, p <0,05, diastolic BP - to 85,8 and 81,7 mm Hg, p=0,059; after 24 weeks

  1. QGQS Granule in SHR Serum Metabonomics Study Based on Tools of UPLC-Q-TOF and Renin-Angiotensin-Aldosterone System Form Protein Profilin-1

    Directory of Open Access Journals (Sweden)

    Ke Li

    2017-01-01

    Full Text Available QGQS granule is effective for the therapeutic of hypertension in clinic. The aim of this research is to observe the antihypertension effect of QGQS granule on SHR and explain the mechanism of its lowering blood pressure. 30 SHR were selected as model group, captopril group, and QGQS group, 10 WKYr were used as control group, and RBP were measured on tail artery consciously. And all the serum sample analysis was carried out on UPLC-TOF-MS system to determine endogenous metabolites and to find the metabonomics pathways. Meanwhile, ELISA kits for the determination pharmacological indexes of PRA, AngI, AngII, and ALD were used for pathway confirmatory; WB for determination of profilin-1 protein expression was conducted for Ang II pathway analysis as well. It is demonstrated that QGQS granule has an excellent therapeutic effect on antihypertension, which exerts effect mainly on metabonomics pathway by regulating glycerophospholipid, sphingolipid, and arachidonic acid metabolism, and it could inhibit the overexpression of the profilin-1 protein. We can come to a conclusion that RAAS should be responsible mainly for the metabonomics pathway of QGQS granule on antihypertension, and it plays a very important role in protein of profilin-1 inhibition.

  2. Between-patient differences in the renal response to renin-angiotensin system intervention : clue to optimising renoprotective therapy?

    NARCIS (Netherlands)

    Laverman, GD; de Zeeuw, D; Navis, G

    2002-01-01

    Renin-angiotensin-aldosterone system (RAAS) blockade with angiotensin-converting enzyme inhibitors (ACE-I) or angiotensin II (Ang II), AT(1)-receptor blockers (ARB) is the cornerstone of renoprotective therapy. Still, the number of patients with end-stage renal disease is increasing worldwide,

  3. The renin-angiotensin system in kidney development

    DEFF Research Database (Denmark)

    Jensen, B L; Stubbe, J; Madsen, K

    2004-01-01

    Recent data from studies in rodents with targeted gene disruption and pharmacological antagonists have shown that the renin-angiotensin-aldosterone system (RAAS) and cyclooxygenase type-2 (COX-2) are necessary for late stages of kidney development. The present review summarizes data on the develo......Recent data from studies in rodents with targeted gene disruption and pharmacological antagonists have shown that the renin-angiotensin-aldosterone system (RAAS) and cyclooxygenase type-2 (COX-2) are necessary for late stages of kidney development. The present review summarizes data...... on the developmental changes of RAAS and COX-2 and the pathways by which they are activated; their possible interplay and the mechanisms by which they affect kidney development. Intrarenal and circulating renin and angiotensin II (ANG II) are stimulated at birth in most mammals. In rats, renin and ANG II stay...

  4. Proteomic prediction and Renin angiotensin aldosterone system Inhibition prevention Of early diabetic nephRopathy in TYpe 2 diabetic patients with normoalbuminuria (PRIORITY) : Essential study design and rationale of a randomised clinical multicentre trial

    NARCIS (Netherlands)

    Lindhardt, Morten; Persson, Frederik; Currie, Gemma; Pontillo, Claudia; Beige, Joachim; Delles, Christian; von der Leyen, Heiko; Mischak, Harald; Navis, Gerjan; Noutsou, Marina; Ortiz, Alberto; Ruggenenti, Piero Luigi; Rychlik, Ivan; Spasovski, Goce; Rossing, Peter

    2016-01-01

    Introduction Diabetes mellitus affects 9% of the European population and accounts for 15% of healthcare expenditure, in particular, due to excess costs related to complications. Clinical trials aiming for earlier prevention of diabetic nephropathy by renin angiotensin system blocking treatment in

  5. Effects of voluntary exercise on blood pressure, angiotensin II, aldosterone, and renal function in two-kidney, one-clip hypertensive rats

    Directory of Open Access Journals (Sweden)

    Waldman BM

    2017-11-01

    Full Text Available Brian M Waldman,1,2 Robert A Augustyniak,1–3 Haiping Chen,1,2 Noreen F Rossi1,2,4 1Department of Internal Medicine, 2Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 3Department of Biomedical Sciences, Edward Via College of Osteopathic Medicine-Carolinas, Spartanburg, SC, 4Department of Internal Medicine, John D Dingell Veterans Administration Medical Center, Detroit, MI, USA Abstract: Spontaneous dynamic exercise promotes sympathoinhibition and decreases arterial pressure in two-kidney, one-clip (2K-1C hypertensive rats. Renal sympathetic nerves stimulate renin secretion and increase renal tubular sodium reabsorption. We hypothesized that daily voluntary wheel running exercise by 2K-1C rats will decrease mean arterial pressure (MAP, plasma angiotensin II (Ang II, and aldosterone as well as normalize urinary sodium and potassium excretion independent of changes in glomerular filtration rate (GFR. Five-week-old male Sprague Dawley rats underwent sham clipping (Sham or right renal artery clipping (2K-1C. Rats were randomized to standard caging (SED or cages with running wheels (EX. After 12 weeks, rats were assigned to either collection of aortic blood for measurement of Ang II and aldosterone or assessment of inulin clearances and excretory function. Running distances were comparable in both EX groups. MAP was lower in 2K-1C EX vs 2K-1C SED rats (P<0.05. Plasma Ang II and aldosterone were significantly higher in 2K-1C SED rats and decreased in 2K-1C EX rats to levels similar to Sham SED or Sham EX rats. Clipped kidney weights were significantly lower in both 2K-1C groups, but GFR and urine flow rates were no different from right and left kidneys among the four groups. Total and fractional sodium excretion rates from the unclipped kidney of 2K-1C SED rats were higher vs either Sham group (P<0.05. Values in 2K-1C EX rats were similar to the Sham groups. Potassium excretion paralleled sodium excretion. These

  6. 21 CFR 862.1045 - Aldosterone test system.

    Science.gov (United States)

    2010-04-01

    ... treatment of primary aldosteronism (a disorder caused by the excessive secretion of aldosterone by the adrenal gland), hypertension caused by primary aldosteronism, selective hypoaldosteronism, edematous...

  7. Central role for sodium in the pathogenesis of blood pressure changes independent of angiotensin, aldosterone and catecholamines in type 1 (insulin-dependent) diabetes mellitus

    DEFF Research Database (Denmark)

    Feldt-Rasmussen, B; Mathiesen, E R; Deckert, T

    1987-01-01

    .41, p less than 0.01). Extracellular volume was increased in patients (p less than 0.05), whereas plasma volume was normal. Supine serum angiotensin II was suppressed in the patients (p less than 0.001). A negative correlation was found between mean blood pressure and supine serum aldosterone (n = 68, r...... = -0.24, p less than 0.05), and exchangeable sodium and aldosterone (n = 66, r = -0.36, p less than 0.002) in all patients. The catecholamine levels were also suppressed or normal in the patients.(ABSTRACT TRUNCATED AT 250 WORDS)...

  8. Angiotensin-I converting enzyme gene and I/D polymorphism ...

    Indian Academy of Sciences (India)

    Angiotensin-I converting enzyme (ACE) gene is one of the most intensely studied genes because of the key role it plays in the renin–angiotensin system (RAS). ACE catalyses the conversion of angiotensin I to angiotensin II, a vasoactive and aldosterone-stimulating peptide, and inactivates bradykinin. (Erdos and Skidgel ...

  9. The renin-angiotensin system and vascular function. The role of angiotensin II, angiotensin-converting enzyme, and alternative conversion of angiotensin I

    NARCIS (Netherlands)

    Roks, A.; Buikema, H.; Pinto, Y. M.; van Gilst, W. H.

    1997-01-01

    The renin-angiotensin system has been implicated in vascular function and disease. Angiotensin-converting enzyme and angiotensin II are believed to be the most important components. However, alternative factors, such as angiotensin-I/II-(1-7) and chymase, have also been shown to be of significance

  10. Renin-angiotensin-aldosterone-blockade is associated with decreased use of antidepressant therapy in patients with type 1 diabetes and diabetic nephropathy.

    Science.gov (United States)

    Ahola, Aila J; Harjutsalo, Valma; Forsblom, Carol; Groop, Per-Henrik

    2014-08-01

    Hypertension and depression are frequent comorbidities of diabetes. Studies suggest that antihypertensive medication affecting the renin-angiotensin-aldosterone system (RAAS) might also relieve depression. Whether this is also seen in patients with type 1 diabetes is not known. We therefore studied whether use of RAAS-modifying medication is associated with reduced antidepressant use in type 1 diabetes. In all, 1,705 participants in the FinnDiane Study were included (57 % men, mean age 46 ± 11 years). Data on medications were obtained from the Drug Prescription Register. Based on their albumin excretion rate (AER), the patients were classified as having normal AER, microalbuminuria, or macroalbuminuria. Diabetic nephropathy was defined as macroalbuminuria or end-stage renal disease (dialysis or renal transplant). A total of 8.4 and 10.9 % of patients with and without RAAS-modifying medication, respectively, had antidepressant medication purchases (NS). In logistic regression analysis, after adjusting for potential confounding factors, use of RAAS-modifying medication was not associated with antidepressant purchases. However, when patients with and without diabetic nephropathy were analyzed separately, RAAS-modifying medication was associated with lower frequency of antidepressant purchases among patients with established diabetic nephropathy. In conclusion, use of RAAS-modifying medication may improve mood in patients with type 1 diabetes and established diabetic nephropathy.

  11. Local renin-angiotensin systems

    NARCIS (Netherlands)

    A.H.J. Danser (Jan)

    1992-01-01

    textabstractThe aim of this thesis was twofold. First, the regional metabolism and production of angiotensin I and angiotensin U were quantified in vivo in man and in anesthetized pigs. This was done by giving constant infusions of radiolabelect J25J-angiotensin I into either a peripheral vein

  12. The role of renin angiotensin system intervention in stage B heart failure.

    LENUS (Irish Health Repository)

    Collier, Patrick

    2012-04-01

    This article outlines the link between the renin angiotensin aldosterone system (RAAS) and various forms of cardiomyopathy, and also reviews the understanding of the effectiveness of RAAS intervention in this phase of ventricular dysfunction. The authors focus their discussion predominantly on patients who have had previous myocardial infarction or those who have left ventricular hypertrophy and also briefly discuss the role of RAAS activation and intervention in patients with alcoholic cardiomyopathy.

  13. Angiotensin-(1-7) is a modulator of the human renin-angiotensin system

    NARCIS (Netherlands)

    Roks, AJM; van Geel, PP; Pinto, YM; Buikema, H; Henning, RH; de Zeeuw, D; van Gilst, WH

    The renin-angiotensin system is important for cardiovascular homeostasis. Currently, therapies for different cardiovascular diseases are based on inhibition of angiotensin-converting enzyme (ACE) or angiotensin II receptor blockade. Inhibition of ACE blocks metabolism of angiotensin-(1-7) to

  14. Angiotensin-(1-7) is a modulator of the human renin-angiotensin system

    NARCIS (Netherlands)

    Roks, A. J.; van Geel, P. P.; Pinto, Y. M.; Buikema, H.; Henning, R. H.; de Zeeuw, D.; van Gilst, W. H.

    1999-01-01

    The renin-angiotensin system is important for cardiovascular homeostasis. Currently, therapies for different cardiovascular diseases are based on inhibition of angiotensin-converting enzyme (ACE) or angiotensin II receptor blockade. Inhibition of ACE blocks metabolism of angiotensin-(1-7) to

  15. The Renal Renin-Angiotensin System

    Science.gov (United States)

    Harrison-Bernard, Lisa M.

    2009-01-01

    The renin-angiotensin system (RAS) is a critical regulator of sodium balance, extracellular fluid volume, vascular resistance, and, ultimately, arterial blood pressure. In the kidney, angiotensin II exerts its effects to conserve salt and water through a combination of the hemodynamic control of renal blood flow and glomerular filtration rate and…

  16. Aldosterone-Sensing Neurons in the NTS Exhibit State-Dependent Pacemaker Activity and Drive Sodium Appetite via Synergy with Angiotensin II Signaling.

    Science.gov (United States)

    Resch, Jon M; Fenselau, Henning; Madara, Joseph C; Wu, Chen; Campbell, John N; Lyubetskaya, Anna; Dawes, Brian A; Tsai, Linus T; Li, Monica M; Livneh, Yoav; Ke, Qingen; Kang, Peter M; Fejes-Tóth, Géza; Náray-Fejes-Tóth, Anikó; Geerling, Joel C; Lowell, Bradford B

    2017-09-27

    Sodium deficiency increases angiotensin II (ATII) and aldosterone, which synergistically stimulate sodium retention and consumption. Recently, ATII-responsive neurons in the subfornical organ (SFO) and aldosterone-sensitive neurons in the nucleus of the solitary tract (NTS HSD2 neurons) were shown to drive sodium appetite. Here we investigate the basis for NTS HSD2 neuron activation, identify the circuit by which NTS HSD2 neurons drive appetite, and uncover an interaction between the NTS HSD2 circuit and ATII signaling. NTS HSD2 neurons respond to sodium deficiency with spontaneous pacemaker-like activity-the consequence of "cardiac" HCN and Na v 1.5 channels. Remarkably, NTS HSD2 neurons are necessary for sodium appetite, and with concurrent ATII signaling their activity is sufficient to produce rapid consumption. Importantly, NTS HSD2 neurons stimulate appetite via projections to the vlBNST, which is also the effector site for ATII-responsive SFO neurons. The interaction between angiotensin signaling and NTS HSD2 neurons provides a neuronal context for the long-standing "synergy hypothesis" of sodium appetite regulation. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Urinary renin-angiotensin markers in polycystic kidney disease

    NARCIS (Netherlands)

    Salih, Mahdi; Bovee, Dominique M.; Roksnoer, Lodi C. W.; Casteleijn, Niek F.; Bakker, Stephan J. L.; Gansevoort, Ronald T.; Zietse, Robert; Danser, A. H. Jan; Hoorn, Ewout J.

    2017-01-01

    In autosomal dominant polycystic kidney disease (ADPKD), activation of the renin-angiotensin aldosterone system (RAAS) may contribute to hypertension and disease progression. Although previous studies have focused on circulating RAAS components, preliminary evidence suggests that APDKD may increase

  18. New Sides of Aldosterone Action in Cardiovascular System as Potential Targets for Therapeutic Intervention.

    Science.gov (United States)

    Kolodziejczyk, Patrycjusz; Gromotowicz-Poplawska, Anna; Aleksiejczuk, Michal; Chabielska, Ewa; Tutka, Piotr; Miltyk, Wojciech

    2018-03-26

    Aldosterone, the main mineralocorticoid hormone, plays a crucial role in the regulation of electrolyte homeostasis and blood pressure. Although, this role is undoubtedly important, it is not a hormonal action that attracts the most attention. Aldosterone seems to be very important important as a local messenger in the pathology of cardiovascular diseases (CVD). In the last few years, the attention was focused on the correlation between raised aldosterone level and increased risk of cardiovascular events. It has been demonstrated that aldosterone contributes to fibrosis, inflammation, endothelial dysfunction, fibrinolytic disordes, and oxidative stress leading to CVD development and progression. It used to be thought that the effects of aldosterone are mediated via classic nuclear receptors - mineralocorticoid receptors (MR). Now we know that the mechanism of aldosterone action in cardiovascular system is much more complex, since experimental and clinical studies indicate that MR blockade may be not sufficient to abolish aldosterone-incuced harmful effects in the cardiovascular system. Therefore, the involvement of some other than MR, receptors and factors is suggested. Moreover, in addition to the generally known genomic action of aldosterone, which involves MR activation, the nongenomic pathways are postulated in the mode of hormone action. More and more attention is focused on the membrane-coupled receptors, which mediate the rapid effects of aldosterone and have been already confirmed in different cells and tissues of a cardiovascular system. The confirmation of multiple mechanisms of aldosterone action opens a new perspective for more effective therapeutic intervention in aldosterone-related CVD. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  19. Evaluation of aldosterone-and cortisol levels in blood plasma in normal conditions of ingestion of sodium and potassium, after saline-increase and depletion, in regard to position, and after stimulation with ACTH and angiotensin II

    International Nuclear Information System (INIS)

    Okada, H.

    1979-01-01

    Methods for the determination of plasma aldosterone and cortisol, by radioimmunoassay, were performed utilizing highly specific antisera. With this methodology it was possible to evaluate cortisol and aldosterone secretion, in six normal subjects, submitted to a basal rice diet on standing and recumbent positions, the effects of exogenous cortrosyn (β1-24 ACTH) and angiotensin II and the same manoevres with progressively increased Na + content of the diet. Aldosterone basal levels decreased with the increase of Na + content in the diet. However, there were no significant differences between the relative increments observed on the recumbent position, at the three levels of sodium intake. The relative increase of plasma aldosterone after ACTH was similar for each basal level of aldosterone induced by different sodium intakes. The responsiveness of aldosterone secretion to cortrosyn and standing position was similar, with no relation to the sodium intake. The infusion of angiotensin II induced an increase in plasma aldosterone, and the relative increment in the levels of the hormone were higher with high sodium than on the rice diet. The average basal cortisol value at the different levels of sodium intake was significantly different being greater on the basal, rice diet, and there was a decrease in cortisol level after recumbency, with the theree diets. The injection of ACTH induced similar cortisol secretion with no relation to the sodium intake. The infusion of non-hypertensive doses of angiotensin II resulted in an anomalous fall in cortisol level, probably because of 'shunt' of substrates to biosynthesis with the added effect of cortisol diurnal rhythmycity. (Author) [pt

  20. The role of angiotensin(1-7) in renal vasculature of the rat

    NARCIS (Netherlands)

    van der Wouden, Els A.; Ochodnický, Peter; van Dokkum, Richard Pe; Roks, Anton Jm; Deelman, Leo E.; de Zeeuw, Dick; Henning, Robert H.

    2006-01-01

    Angiotensin(1-7) is an active component of the renin-angiotensin-aldosterone system. Its exact role in renal vascular function is unclear. We therefore studied the effects of angiotensin(1-7) on the renal vasculature in vitro and in vivo. Isolated small renal arteries were studied in an arteriograph

  1. The role of angiotensin(1-7) in renal vasculature of the rat

    NARCIS (Netherlands)

    van der Wouden, Els A.; Ochodnicky, Peter; van Dokkum, Richard P. E.; Roks, Anton J. M.; Deelman, Leo E.; de Zeeuw, Dick; Henning, Robert H.

    2006-01-01

    Objective Angiotensin(1-7) is an active component of the renin-angiotensin-aldosterone system. Its exact role in renal vascular function is unclear. We therefore studied the effects of angiotensin(1-7) on the renal vasculature in vitro and in vivo. Methods Isolated small renal arteries were studied

  2. Raised plasma aldosterone and natriuretic peptides in atrial fibrillation

    DEFF Research Database (Denmark)

    Dixen, U; Ravn, L; Soeby-Rasmussen, C

    2007-01-01

    During atrial fibrillation (AF), the renin-angiotensin-aldosterone system (RAAS) may be activated. In this study, our aim was to evaluate at a long-term follow-up visit the levels of plasma aldosterone and natriuretic peptides as markers of neurohormonal remodeling in patients with earlier......, documented AF in relation to present heart rhythm, clinical data, and the left ventricular ejection fraction (LVEF). We hypothesized that increased levels of aldosterone and natriuretic peptides were significantly associated with present AF as markers of RAAS activation during the arrhythmia....

  3. Raised Plasma Aldosterone and Natriuretic Peptides in Atrial Fibrillation

    DEFF Research Database (Denmark)

    Dixen, Ulrik; Ravn, Lasse Steen; Soeby-Rasmussen, Christian

    2006-01-01

    BACKGROUND AND AIMS: During atrial fibrillation (AF), the renin-angiotensin-aldosterone system (RAAS) may be activated. In this study, our aim was to evaluate at a long-term follow-up visit the levels of plasma aldosterone and natriuretic peptides as markers of neurohormonal remodeling in patients...... with earlier, documented AF in relation to present heart rhythm, clinical data, and the left ventricular ejection fraction (LVEF). We hypothesized that increased levels of aldosterone and natriuretic peptides were significantly associated with present AF as markers of RAAS activation during the arrhythmia...

  4. Effects of truncated angiotensins in humans after double blockade of the renin system

    DEFF Research Database (Denmark)

    Plovsing, Ronni R; Wamberg, Christian; Sandgaard, Niels C F

    2003-01-01

    -sodium diet (30 mmol/day). The subjects were acutely pretreated with canrenoate and captopril to inhibit aldosterone actions and ANG II synthesis, respectively. ANG II infusion increased plasma angiotensin immunoreactivity to 53 +/- 6 pg/ml (+490%), plasma aldosterone to 342 +/- 38 pg/ml (+109%), and blood...

  5. Angiotensin-converting enzyme 2, Angiotensin-(1-7) and Mas: new players of the Renin Angiotensin System

    DEFF Research Database (Denmark)

    Santos, Robson AS; Ferreira, Anderson J; Verano-Braga, Thiago

    2013-01-01

    Angiotensin(Ang)-(1-7) is now recognized as a biologically active component of renin-angiotensin system (RAS). Ang-(1-7) appears to play a central role in the RAS because it exerts a vast array of actions, many of them opposite to those attributed to the main effector peptide of the RAS, Ang II. ...

  6. Interactive roles of NPR1 gene-dosage and salt diets on cardiac angiotensin II, aldosterone and pro-inflammatory cytokines levels inmutantmice

    Science.gov (United States)

    Zhao, Di; Das, Subhankar; Pandey, Kailash N.

    2015-01-01

    Objective The objective of the present study was to elucidate the interactive roles of guanylyl cyclase/natriuretic peptide receptor-A (NPRA) gene (Npr1) and salt diets on cardiac angiotensin II (ANG II), aldosterone and proinflammatory cytokines levels in Npr1 gene-targeted (1-copy, 2-copy, 3-copy, 4-copy) mice. Methods Npr1 genotypes included 1-copy gene-disrupted heterozygous (+/−), 2-copy wild-type (+/+), 3-copy gene-duplicated heterozygous (++/+) and 4-copy gene-duplicated homozygous (++/++) mice. Animals were fed low, normal and high-salt diets. Plasma and cardiac levels of ANG II, aldosterone and pro-inflammatory cytokines were determined. Results With a high-salt diet, cardiac ANG II levels were increased (+) in 1-copy mice (13.7 ± 2.8 fmol/mg protein, 111%) compared with 2-copy mice (6.5 ± 0.6), but decreased (−) in 4-copy (4.0 ± 0.5, 38%) mice. Cardiac aldosterone levels were increased (+) in 1-copy mice (80 ± 4 fmol/mg protein, 79%) compared with 2-copy mice (38 ± 3). Plasma tumour necrosis factor alpha was increased (+) in 1-copy mice (30.27 ± 2.32 pg/ml, 38%), compared with 2-copy mice (19.36 ± 2.49, 24%), but decreased (−) in 3-copy (11.59 ± 1.51, 12%) and 4-copy (7.13 ± 0.52, 22%) mice. Plasma interleukin (IL)-6 and IL-1α levels were also significantly increased (+) in 1-copy compared with 2-copy mice but decreased (−) in 3-copy and 4-copy mice. Conclusion These results demonstrate that a high-salt diet aggravates cardiac ANG II, aldosterone and proinflammatory cytokine levels in Npr1 gene-disrupted 1-copy mice, whereas, in Npr1 gene-duplicated (3-copy and 4-copy) mice, high salt did not render such elevation, suggesting the potential roles of Npr1 against salt loading. PMID:23188418

  7. Response to angiotensin-converting enzyme inhibition is selectively blunted by high sodium in angiotensin-converting enzyme DD genotype : Evidence for gene-environment interaction in healthy volunteers

    NARCIS (Netherlands)

    Lely, A. Titia; Lambers Heerspink, Hiddo J.; Zuurman, Mike; Visser, Folkert W.; Kocks, Menno J. A.; Boomsma, Frans; Navis, Gerjan

    2010-01-01

    Background Renin-angiotensin-aldosterone system blockade is a cornerstone in cardiovascular protection. Angiotensin-converting enzyme (ACE)-DD genotype has been associated with resistance to angiotensin-converting enzyme inhibition (ACEi), but data are conflicting. As sodium intake modifies the

  8. Beta-blocker, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, nitrate-hydralazine, diuretics, aldosterone antagonist, ivabradine, devices and digoxin (BANDAID(2) ): an evidence-based mnemonic for the treatment of systolic heart failure.

    Science.gov (United States)

    Chia, N; Fulcher, J; Keech, A

    2016-06-01

    Heart failure causes significant morbidity and mortality, with recognised underutilisation rates of guideline-based therapies. Our aim was to review current evidence for heart failure treatments and derive a mnemonic summarising best practice, which might assist physicians in patient care. Treatments were identified for review from multinational society guidelines and recent randomised trials, with a primary aim of examining their effects in systolic heart failure patients on mortality, hospitalisation rates and symptoms. Secondary aims were to consider other clinical benefits. MEDLINE and EMBASE were searched using a structured keyword strategy and the retrieved articles were evaluated methodically to produce an optimised reference list for each treatment. We devised the mnemonic BANDAID (2) , standing for beta-blocker, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, nitrate-hydralazine (or potentially neprilysin inhibitor), diuretics, aldosterone antagonist, ivabradine, devices (automatic implantable cardioverter defibrillator, cardiac resynchronisation therapy or both) and digoxin as a representation of treatments with strong evidence for their use in systolic heart failure. Treatment with omega-3 fatty acids, statins or anti-thrombotic therapies has limited benefits in a general heart failure population. Adoption of this mnemonic for current evidence-based treatments for heart failure may help improve prescribing rates and patient outcomes in this debilitating, high mortality condition. © 2016 Royal Australasian College of Physicians.

  9. Recent insights and therapeutic perspectives of angiotensin-(1-9) in the cardiovascular system.

    Science.gov (United States)

    Ocaranza, Maria Paz; Michea, Luis; Chiong, Mario; Lagos, Carlos F; Lavandero, Sergio; Jalil, Jorge E

    2014-11-01

    Chronic RAS (renin-angiotensin system) activation by both AngII (angiotensin II) and aldosterone leads to hypertension and perpetuates a cascade of pro-hypertrophic, pro-inflammatory, pro-thrombotic and atherogenic effects associated with cardiovascular damage. In 2000, a new pathway consisting of ACE2 (angiotensin-converting enzyme2), Ang-(1-9) [angiotensin-(1-9)], Ang-(1-7) [angiotensin-(1-7)] and the Mas receptor was discovered. Activation of this novel pathway stimulates vasodilation, anti-hypertrophy and anti-hyperplasia. For some time, studies have focused mainly on ACE2, Ang-(1-7) and the Mas receptor, and their biological properties that counterbalance the ACE/AngII/AT1R (angiotensin type 1 receptor) axis. No previous information about Ang-(1-9) suggested that this peptide had biological properties. However, recent data suggest that Ang-(1-9) protects the heart and blood vessels (and possibly the kidney) from adverse cardiovascular remodelling in patients with hypertension and/or heart failure. These beneficial effects are not modified by the Mas receptor antagonist A779 [an Ang-(1-7) receptor blocker], but they are abolished by the AT2R (angiotensin type 2 receptor) antagonist PD123319. Current information suggests that the beneficial effects of Ang-(1-9) are mediated via the AT2R. In the present review, we summarize the biological effects of the novel vasoactive peptide Ang-(1-9), providing new evidence of its cardiovascular-protective activity. We also discuss the potential mechanism by which this peptide prevents and ameliorates the cardiovascular damage induced by RAS activation.

  10. Renal graft failure after addition of an angiotensin II receptor antagonist to an angiotensin-converting enzyme inhibitor

    DEFF Research Database (Denmark)

    Kamper, Anne-Lise; Nielsen, Arne Høj; Baekgaard, Niels

    2002-01-01

    Combined treatment with an angiotensin-converting enzyme (ACE) inhibitor and an angiotensin II (Ang II) receptor blocker (ARB) has been suggested in order to achieve a more complete blockade of the renin-angiotensin-aldosterone system in cardiovascular and renal disease. The present report descri...... describes a case of acute renal graft dysfunction following the addition of an ARB to existing ACE inhibition. This unmasked an unknown iliac artery stenosis. The case indicates a possible important role of Ang II generated by non-ACE pathways in this situation.......Combined treatment with an angiotensin-converting enzyme (ACE) inhibitor and an angiotensin II (Ang II) receptor blocker (ARB) has been suggested in order to achieve a more complete blockade of the renin-angiotensin-aldosterone system in cardiovascular and renal disease. The present report...

  11. The Protective Arm of the Renin Angiotensin System (RAS)

    DEFF Research Database (Denmark)

    will become of major medical importance in the near future. Focusing on recent research, The Protective Arm of the Renin Angiotensin System presents a host of new experimental studies on specific components of the RAS, namely angiotensin AT2 receptors (AT2R), the angiotensin (1-7) peptide with its receptor...... understanding of the protective side of the Renin Angiotensin System (RAS) involving angiotensin AT2 receptor, ACE2, and Ang(1-7)/Mas receptor Combines the knowledge of editors who pioneered research on the protective renin angiotensin system including; Dr. Thomas Unger, one of the founders of AT2 receptor...... research; Dr. Ulrike M. Steckelings, who contributed significantly to first preclinical studies with a novel specific AT2-agonist, and Dr. Robson Santos who pioneered research on angiotensin-(1-7) and its receptor Mas. Shows that the protective RAS axes are able to ameliorate the course of several...

  12. Classical Renin-Angiotensin system in kidney physiology.

    Science.gov (United States)

    Sparks, Matthew A; Crowley, Steven D; Gurley, Susan B; Mirotsou, Maria; Coffman, Thomas M

    2014-07-01

    The renin-angiotensin system has powerful effects in control of the blood pressure and sodium homeostasis. These actions are coordinated through integrated actions in the kidney, cardiovascular system and the central nervous system. Along with its impact on blood pressure, the renin-angiotensin system also influences a range of processes from inflammation and immune responses to longevity. Here, we review the actions of the "classical" renin-angiotensin system, whereby the substrate protein angiotensinogen is processed in a two-step reaction by renin and angiotensin converting enzyme, resulting in the sequential generation of angiotensin I and angiotensin II, the major biologically active renin-angiotensin system peptide, which exerts its actions via type 1 and type 2 angiotensin receptors. In recent years, several new enzymes, peptides, and receptors related to the renin-angiotensin system have been identified, manifesting a complexity that was previously unappreciated. While the functions of these alternative pathways will be reviewed elsewhere in this journal, our focus here is on the physiological role of components of the "classical" renin-angiotensin system, with an emphasis on new developments and modern concepts. © 2014 American Physiological Society.

  13. ALDOSTERONE ANTAGONISTS. MODERN VIEWS ON THE MECHANISM OF ACTION AND EFFECTS OF SPIRONOLACTONE

    Directory of Open Access Journals (Sweden)

    V. I. Podzolkov

    2017-01-01

    Full Text Available The importance of renin-angiotensin-aldosterone system in pathogenesis of different clinical conditions is studied well. The key role of aldosterone receptor blockers, particularly spironolactone, in treatment of such conditions as primary hyperaldosteronism, resistant hypertension, edematous syndrome in congestive heart failure, nephrotic syndrome, and portal cirrhosis is considered in the article. Development of ideas about cardio-, vaso- and nephroprotective effects of these drugs is highlighted as well as their influence on patient prognosis.

  14. RU28318, an Aldosterone Antagonist, in Combination with an ACE Inhibitor and Angiotensin Receptor Blocker Attenuates Cardiac Dysfunction in Diabetes

    Directory of Open Access Journals (Sweden)

    Ibrahim F. Benter

    2013-01-01

    Full Text Available Aims. We evaluated the effects of RU28318 (RU, a selective mineralocorticoid receptor (MR antagonist, Captopril (Capt, an angiotensin converting enzyme inhibitor, and Losartan (Los, an angiotensin receptor blocker, alone or in combination with ischemia/reperfusion- (I/R- induced cardiac dysfunction in hearts obtained from normal and diabetic rats. Methods. Isolated hearts were perfused for 30 min and then subjected to 30 min of global ischemia (I followed by a period of 30 min of reperfusion (R. Drugs were administered for 30 min either before or after ischemia. Drug regimens tested were RU, Capt, Los, RU + Capt, RU + Los, Capt + Los, and RU + Capt + Los (Triple. Recovery of cardiac hemodynamics was evaluated. Results. Recovery of cardiac function was up to 5-fold worse in hearts obtained from diabetic animals compared to controls. Treatment with RU was generally better in preventing or reversing ischemia-induced cardiac dysfunction in normal hearts compared to treatment with Capt or Los alone. In diabetic hearts, RU was generally similarly effective as Capt or Los treatment. Conclusions. RU treatment locally might be considered as an effective therapy or preventative measure in cardiac I/R injury. Importantly, RU was the most effective at improving -dP/dt (a measure of diastolic function when administered to diabetic hearts after ischemia.

  15. [The acute effects of the new angiotensin I-converting enzyme inhibitor, enalapril maleate, on blood pressure, plasma renin, aldosterone and kinins in hypertensive patients].

    Science.gov (United States)

    Gotoh, M; Mizuno, K; Hashimoto, S; Kunii, N; Fukuchi, S

    1985-05-20

    The acute antihypertensive effect of a new long-acting oral angiotensin I-converting enzyme (ACE) inhibitor, enalapril maleate, was assessed in 20 hypertensive patients, of whom 14 had essential hypertension, 4 had renovascular hypertension, one had hypertension associated with chronic renal failure, and one had primary aldosteronism. Enalapril maleate significantly lowered the blood pressure in either low-renin or normal- and high-renin hypertensives. There was a significant correlation for all patients as a group between the pretreatment levels of serum ACE activity and the reduction in mean blood pressure (r = -0.454, p less than 0.05, n = 20) 2 h after drug administration. The serum ACE activity decreased maximally 3 to 4 hours after drug administration and did not return to baseline levels within 24 h. There was a significant correlation between the reduction in mean blood pressure and changes in ACE activity 90 min and 2 h after drug administration, respectively, for all patients as a group (r = 0.495, p less than 0.05, n = 20, at 90 min; r = 0.508, p less than 0.05, n = 20, at 2 h). The plasma renin activity (PRA) significantly increased in normal- and high-renin hypertensives but not in low-renin hypertensives. There was a close correlation between the reduction in mean blood pressure and the PRA 8 h after drug administration in normal- and high-renin patients (r = -0.623, p less than 0.05, n = 13), while no such relationship was observed in low-renin patients. The plasma aldosterone concentration (PAC) significantly decreased within 3 h, the lowest values occurring at 8 h after drug administration, and it returned to baseline levels within 24 h in all patients. No relationship was found between the reduction in mean blood pressure and changes in PAC after drug administration in either low-renin or normal- and high-renin hypertensives. The plasma bradykinin concentration (PBC) increased within 1 h, the highest values occurring at 3 h after drug

  16. Regression of cardiac hypertrophy in the SHR by combined renin-angiotensin system blockade and dietary sodium restriction

    Directory of Open Access Journals (Sweden)

    Emad Abro

    2001-03-01

    Full Text Available Altered operation of the renin-angiotensin-aldosterone system (RAAS and dietary sodium intake have been identified as independent risk factors for cardiac hypertrophy. The way in which sodium intake and the operation of the renin-angiotensin-aldosterone system interact in the pathogenesis of cardiac hypertrophy is poorly understood. The aims of this study were to investigate the cardiac effects of the renin-angiotensin system (RAS blockade in the spontaneously hypertensive rat (SHR, using co-treatment with an angiotensin II receptor blocker (ARB and an angiotensin-converting enzyme (ACE inhibitor with different sodium intakes. Our experiments with SHR show that, at high levels of sodium intake (4.0%, aggressive RAS blockade treatment with candesartan (3 mg/kg and perindopril (6 mg/kg does not result in regression of cardiac hypertrophy. In contrast, RAS blockade coupled with reduced sodium diet (0.2% significantly regresses cardiac hypertrophy, impairs animal growth and is associated with elevated plasma renin and dramatically suppressed plasma angiotensinogen levels. Histological analyses indicate that the differential effect of reduced sodium on heart growth during RAS blockade is not associated with any change in myocardial interstitial collagen, but reflects modification of cellular geometry. Dimensional measurements of enzymatically-isolated ventricular myocytes show that, in the RAS blocked, reduced sodium group, myocyte length and width were decreased by about 16—19% compared with myocytes from the high sodium treatment group. Our findings highlight the importance of `titrating' sodium intake with combined RAS blockade in the clinical setting to optimise therapeutic benefit.

  17. Renin–angiotensin–aldosterone system related gene polymorphisms and urinary total arsenic is related to chronic kidney disease

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Wei-Jen [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Huang, Ya-Li [Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Shiue, Horng-Sheng [Department of Chinese Medicine, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan (China); Chen, Tzen-Wen [Division of Nephrology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan (China); Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Lin, Yuh-Feng [Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Division of Nephrology, Department of Internal Medicine, Shuang Ho Hospital, New Taipei, Taiwan (China); Huang, Chao-Yuan [Department of Urology, National Taiwan University Hospital, College of Medicine National Taiwan University, Taipei, Taiwan (China); Lin, Ying-Chin [Department of Family Medicine, Shung Ho Hospital, Taipei Medical University, New Taipei, Taiwan (China); Department of Health Examination, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan (China); Division of Family Medicine, School of Medicine, Taipei Medical University, Taipei, Taiwan (China); Han, Bor-Cheng [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Hsueh, Yu-Mei, E-mail: ymhsueh@tmu.edu.tw [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China)

    2014-09-01

    A recent study demonstrated that an increased risk of chronic kidney disease (CKD) was associated with high urinary total arsenic levels. However, whether genomic instability is related to CKD remains unclear. An association between CKD and genetic polymorphisms of regulation enzymes of the renin–angiotensin–aldosterone system (RAAS), such as angiotensin-converting enzyme (ACE), angiotensinogen (AGT), angiotensin II type I receptor (AT1R), and aldosterone synthase (CYP11B2) has not been shown. The aim of the present study was to investigate the relationship between arsenic, genetic polymorphisms of RAAS enzymes and CKD. A total of 233 patients and 449 age- and gender-matched controls were recruited from the Taipei Medical University Hospital, Taipei Municipal Wan Fang Hospital and the Shin Kong Wu Ho-Su Memorial Hospital. Concentrations of urinary arsenic were determined by a high-performance liquid chromatography-linked hydride generator, and atomic absorption spectrometry. Polymorphisms of ACE(I/D), AGT(A[− 20]C), (T174M), (M235T), AT1R(A1166C) and CYP11B2(C[− 344]T) were examined by polymerase chain reaction and restriction fragment length polymorphism. Subjects carrying the CYP11B2 TT genotype had a higher odds ratio (OR), 1.39 (0.96–2.01), of CKD; while those with the AGT(A[− 20]C) CC genotype had an inverse OR of CKD (0.20 (0.05–0.81)), and a high-risk genotype was defined as A/A + A/C for AGT(A[− 20C]) and T/T for CYP11B2(C[− 344]T). The trend test showed a higher OR for CKD in patients who had either high urinary total arsenic levels or carried the high-risk genotype, or both, compared to patients with low urinary total arsenic levels, who carried the low-risk genotype, and could also be affected by the hypertension or diabetes status. - Highlights: • AGT(− 20 C) and CYP11B2(− 344 T) genotypes were significantly associated with CKD. • Combined effect of high-risk genotypes and high urinary total arsenic on OR of CKD. • Combined

  18. Aldosterone breakthrough during aliskiren, valsartan, and combination (aliskiren + valsartan) therapy.

    Science.gov (United States)

    Bomback, Andrew S; Rekhtman, Yelena; Klemmer, Philip J; Canetta, Pietro A; Radhakrishnan, Jai; Appel, Gerald B

    2012-01-01

    Aldosterone levels increase in 30%-40% of patients on angiotensin-converting enzyme inhibitors and/or angiotensin receptor blockers over the long term. This "aldosterone breakthrough" may carry important clinical consequences given aldosterone's nonepithelial, pro-fibrotic actions. The renin inhibitor, aliskiren, by suppressing the renin-angiotensin-aldosterone system (RAAS) proximally, may limit breakthrough compared to conventional RAAS blockade. This open-label study (NCT01129557) randomized subjects to aliskiren 300 mg daily (A), valsartan 320 mg daily (V), or aliskiren 150 mg + valsartan 160 mg daily (A+V) for 9 months. Eligible subjects had proteinuria >300 mg/day, estimated glomerular filtration rate (eGFR) >45 mL/min/1.73 m(2), and systolic blood pressure (BP) >130 or diastolic BP >80 mm Hg. Serum and 24-hour urine aldosterone (indexed to 24-hour urine Na) were checked before initiation of therapy and at 3, 6, and 9 months. Aldosterone breakthrough was defined as a sustained increase from baseline aldosterone by study end. The study was intended to enroll 120 subjects but was terminated early by the sponsor. We present here the results of 33 subjects who completed the protocol, of which 12 were randomized to A, 11 were randomized to V, and 10 were randomized to A+V. Mean baseline eGFR was 75.5 (±23.3) mL/min/1.73 m(2); baseline proteinuria was 3104 (±2943) mg/day; and baseline BP was 134.7 (±10.5)/84.8 (±8.4) mm Hg. Three (27%) subjects on V, three (25%) subjects on A, and three (30%) subjects on A+V had aldosterone breakthrough. Mean proteinuria reduction was 31% from baseline in all subjects: 30% in subjects with breakthrough vs. 32% in subjects without breakthrough. Mean BP reduction was 11.0/8.8 mm Hg in all subjects: 8.4/6.1 mm Hg in subjects with breakthrough vs. 12.0/9.8 mm Hg in subjects without breakthrough. Aliskiren, alone or in combination with valsartan, did not reduce the incidence of aldosterone breakthrough in subjects with hypertension

  19. Renin-Angiotensin System Blockade Associated with Statin Improves Endothelial Function in Diabetics

    Directory of Open Access Journals (Sweden)

    Ronaldo Altenburg Gismondi

    2015-01-01

    Full Text Available AbstractBackground:Studies suggest that statins have pleiotropic effects, such as reduction in blood pressure, and improvement in endothelial function and vascular stiffness.Objective:To analyze if prior statin use influences the effect of renin-angiotensin-aldosterone system inhibitors on blood pressure, endothelial function, and vascular stiffness.Methods:Patients with diabetes and hypertension with office systolic blood pressure ≥ 130 mmHg and/or diastolic blood pressure ≥ 80 mmHg had their antihypertensive medications replaced by amlodipine during 6 weeks. They were then randomized to either benazepril or losartan for 12 additional weeks while continuing on amlodipine. Blood pressure (assessed with ambulatory blood pressure monitoring, endothelial function (brachial artery flow-mediated dilation, and vascular stiffness (pulse wave velocity were evaluated before and after the combined treatment. In this study, a post hoc analysis was performed to compare patients who were or were not on statins (SU and NSU groups, respectively.Results:The SU group presented a greater reduction in the 24-hour systolic blood pressure (from 134 to 122 mmHg, p = 0.007, and in the brachial artery flow-mediated dilation (from 6.5 to 10.9%, p = 0.003 when compared with the NSU group (from 137 to 128 mmHg, p = 0.362, and from 7.5 to 8.3%, p = 0.820. There was no statistically significant difference in pulse wave velocity (SU group: from 9.95 to 9.90 m/s, p = 0.650; NSU group: from 10.65 to 11.05 m/s, p = 0.586.Conclusion:Combined use of statins, amlodipine, and renin-angiotensin-aldosterone system inhibitors improves the antihypertensive response and endothelial function in patients with hypertension and diabetes.

  20. Aging and Human Hormonal and Pressor Responsiveness to Angiotensin II Infusion With Simultaneous Measurement of Exogenous and Endogenous Angiotensin II

    OpenAIRE

    Duggan, Joseph; Nussberger, Juerg; Kilfeather, S.; O'Malley, K.

    2017-01-01

    A decline in the function of the renin angiotensin aldosterone system may induce adaptive changes in response to angiotensin II (ANG II) with age. We have examined platelet ANG II receptor density, blood pressure and aldosterone responses to ANG II [Asn1, Val5-ANG II] (Hypertensin, Ciba Geigy, Horsham, Sussex, England) infusion in 8 young, 24 to 30 years, and 8 older, 54 to 65 years, healthy volunteers. To measure circulating ANG II, we established a new method for specific and simultaneous m...

  1. Renal effects of the angiotensin receptor neprilysin inhibitor LCZ696 in patients with heart failure and preserved ejection fraction

    NARCIS (Netherlands)

    Voors, Adriaan A.; Gori, Mauro; Liu, Licette C. Y.; Claggett, Brian; Zile, Michael R.; Pieske, Burkert; McMurray, John J. V.; Packer, Milton; Shi, Victor; Lefkowitz, Martin P.; Solomon, Scott D.

    BackgroundIncreases in serum creatinine with renin-angiotensin-aldosterone system (RAAS) inhibitors can lead to unnecessary discontinuation of these agents. The dual-acting angiotensin receptor neprilysin inhibitor LCZ696 improves clinical outcome patients with heart failure with reduced ejection

  2. 21 CFR 862.1090 - Angiotensin converting enzyme (A.C.E.) test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Angiotensin converting enzyme (A.C.E.) test system... Test Systems § 862.1090 Angiotensin converting enzyme (A.C.E.) test system. (a) Identification. An angiotensin converting enzyme (A.C.E.) test system is a device intended to measure the activity of angiotensin...

  3. Effect of swimming on the production of aldosterone in rats.

    Directory of Open Access Journals (Sweden)

    Fu-Kong Lieu

    Full Text Available It has been demonstrated that exercise is one of the stresses known to increase the aldosterone secretion. Both potassium and angiotensin II (Ang II levels are shown to be correlated with aldosterone production during exercise, but the mechanism is still unclear. In an in vivo study, male rats were catheterized via right jugular vein (RJV, and divided into four groups namely water immersion, swimming, lactate infusion (13 mg/kg/min and pyruvate infusion (13 mg/kg/min groups. Each group was treated for 10 min. Blood samples were collected at 0, 10, 15, 30, 60 and 120 min from RJV after administration. In an in vitro study, rat zona glomerulosa (ZG cells were challenged by lactate (1-10 mM in the presence or absence of Ang II (10(-8 M for 60 min. The levels of aldosterone in plasma and medium were measured by radioimmunoassay. Cell lysates were analyzed by immunoblotting assay. After exercise and lactate infusion, plasma levels of aldosterone and lactate were significantly higher than those in the control group. Swimming for 10 min significantly increased the plasma Ang II levels in male rats. Administration of lactate plus Ang II significantly increased aldosterone production and enhanced protein expression of steroidogenic acute regulatory protein (StAR in ZG cells. These results demonstrated that acute exercise led to the increase of both aldosterone and Ang II secretion, which is associated with lactate action on ZG cells and might be dependent on the activity of renin-angiotensin system.

  4. The renin-angiotensin system: a possible new target for depression.

    Science.gov (United States)

    Vian, João; Pereira, Círia; Chavarria, Victor; Köhler, Cristiano; Stubbs, Brendon; Quevedo, João; Kim, Sung-Wan; Carvalho, André F; Berk, Michael; Fernandes, Brisa S

    2017-08-01

    Depression remains a debilitating condition with an uncertain aetiology. Recently, attention has been given to the renin-angiotensin system. In the central nervous system, angiotensin II may be important in multiple pathways related to neurodevelopment and regulation of the stress response. Studies of drugs targeting the renin-angiotensin system have yielded promising results. Here, we review the potential beneficial effects of angiotensin blockers in depression and their mechanisms of action. Drugs blocking the angiotensin system have efficacy in several animal models of depression. While no randomised clinical trials were found, case reports and observational studies showed that angiotensin-converting enzyme inhibitors or angiotensin receptor blockers had positive effects on depression, whereas other antihypertensive agents did not. Drugs targeting the renin-angiotensin system act on inflammatory pathways implicated in depression. Both preclinical and clinical data suggest that these drugs possess antidepressant properties. In light of these results, angiotensin system-blocking agents offer new horizons in mood disorder treatment.

  5. Renin angiotensin system blockers-associated angioedema in the Thai population: analysis from Thai National Pharmacovigilance Database.

    Science.gov (United States)

    Win, Thet Su Zin; Chaiyakunapruk, Nathorn; Suwankesawong, Wimon; Dilokthornsakul, Piyameth; Nathisuwan, Surakit

    2015-09-01

    Renin-angiotensin-aldosterone system (RAS) blockers are commonly used for cardiovascular diseases. Currently, little information exists for the Asian population on angioedema, a rare yet serious adverse event. This study aimed to describe characteristics of RAS blockers-associated angioedema (RASBA) in Thai patients. A retrospective study using the national pharmacovigilance database of Thailand was undertaken. Cases indicating the presence of angioedema with RAS blockers uses from 1984-2011 were identified. Patient demographics, co-morbidities, concomitant drugs, information for the RAS blockers and angioedema were obtained as well as causality assessment and quality of reports. A total of 895 cases were identified. Mean age was 59.9+12.8 years and 66.5% being female. Most angioedema events (48.6%) occurred during the first week of treatment. Angiotensin converting enzyme inhibitors (87.7%) were the most commonly implicated agents followed by angiotensin receptor blockers (10.5%), aldosterone antagonist (2.1%) and direct renin inhibitor (0.2%). Out of the 895 cases incorporated in this study, 165 (18.4%) were classified as serious events and resulted in hospitalization. The overall case fatality rate was 0.4%. Respiratory disturbance occurred in 46 cases (5.1%). Patients with respiratory complications tended to be younger (53.4+13.9 vs 60.3+12.7 years old; p=0.002) and with higher frequency of allergy history (26.1% vs 14.7%; p=0.032) compared to those without respiratory complications. Based on multivariate logistic regression, the adjusted OR for history of allergy was 2.23 (95%CI: 1.04 - 4.78, p = 0.041). RASBA in Thai population occurred mostly in elderly female patients and often led to hospitalization. Since large number of patients is regularly exposed to RAS-blockers, a nationwide attempt to raise awareness of clinicians when prescribing RAS-blockers is prudent.

  6. Renal graft failure after addition of an angiotensin II receptor antagonist to an angiotensin-converting enzyme inhibitor

    DEFF Research Database (Denmark)

    Kamper, Anne-Lise; Nielsen, Arne Høj; Baekgaard, Niels

    2002-01-01

    Combined treatment with an angiotensin-converting enzyme (ACE) inhibitor and an angiotensin II (Ang II) receptor blocker (ARB) has been suggested in order to achieve a more complete blockade of the renin-angiotensin-aldosterone system in cardiovascular and renal disease. The present report...... describes a case of acute renal graft dysfunction following the addition of an ARB to existing ACE inhibition. This unmasked an unknown iliac artery stenosis. The case indicates a possible important role of Ang II generated by non-ACE pathways in this situation....

  7. Increased Dietary Salt Changes Baroreceptor Sensitivity and Intrarenal Renin-Angiotensin System in Goldblatt Hypertension.

    Science.gov (United States)

    Shimoura, Caroline G; Lincevicius, Gisele S; Nishi, Erika E; Girardi, Adriana C C; Simon, Karin A; Bergamaschi, Cassia T; Campos, Ruy R

    2017-01-01

    Renovascular hypertension (2-kidney 1-clip model (2K1C)) is characterized by renin-angiotensin system (RAS) activation. Increased Angiotensin II (AngII) leads to sympathoexcitation, oxidative stress, and alterations in sodium and water balance. The aim of this study was to evaluate whether a discrete increase in sodium chloride intake in 2K1C rats leads to changes in cardiovascular and autonomic function, oxidative stress, and renin angiotensin aldosterone system. After 4 weeks of induction of hypertension, rats were fed a normal sodium diet (0.4% NaCl) or a high-sodium diet (2% NaCl) for 2 consecutive weeks. Experiments were carried out for 6 weeks after clipping. Mean arterial pressure (MAP), renal sympathetic nerve activity (rSNA), arterial baroreflex control of rSNA, and heart rate (HR) were assessed. Thiobarbituric acid reactive substances and glutathione were measured as indicators of systemic oxidative stress. Angiostensin-converting enzyme (ACE), ACE2, and angiotensinogen were evaluated in clipped and unclipped kidneys as also urinary angiotensinogen and plasma renin activity. Angiotensinogen, plasma renin activity (PRA) and angiotensin-converting enzyme (ACE) and ACE2 in clipped and unclipped kidneys were evaluated. High-sodium diet did not change systemic oxidative stress, and basal values of MAP, HR, or rSNA; however, increased renal (-0.7±0.2 vs. -1.5±0.1 spikes/s/mm Hg) and cardiac (-0.9±0.14 vs. -1.5±0.14 bpm/mm Hg) baroreceptor reflex sensitivity in 2K1C rats. Although there was no alteration in PRA, a high-salt diet significantly decreased urinary angiotensinogen, ACE, and ACE2 expressions in the clipped and unclipped kidneys. Increased arterial baroreceptor control associated with a suppression of the intrarenal RAS in the 2K1C rats on high-salt diet provide a salt-resistant effect on hypertension and sympathoexcitation in renovascular hypertensive rats. © American Journal of Hypertension, Ltd 2016. All rights reserved. For Permissions, please

  8. Combined use of nonsteroidal anti-inflammatory drugs with diuretics and/or renin-angiotensin system inhibitors in the community increases the risk of acute kidney injury.

    Science.gov (United States)

    Dreischulte, Tobias; Morales, Daniel R; Bell, Samira; Guthrie, Bruce

    2015-08-01

    Nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with an increased risk of acute kidney injury (AKI) when used in triple combination with renin-angiotensin system inhibitors and diuretics, but previous research reported that NSAIDs in dual combinations with either renin-angiotensin system inhibitors or diuretics alone were not. However, earlier studies relied on hospital coding to define AKI, which may underestimate true risk. This nested case-control study characterized the risk of community-acquired AKI associated with NSAID use among 78,379 users of renin-angiotensin system inhibitors and/or diuretics, where AKI was defined as a 50% or greater increase in creatinine from baseline. The AKI incidence was 68/10,000 person-years. The relative increase in AKI risk was similar for NSAID use in both triple (adjusted rate ratio 1.64 (95% CI 1.25-2.14)) and dual combinations with either renin-angiotensin system inhibitors (1.60 (1.18-2.17)) or diuretics (1.64 (1.17-2.29)). However, the absolute increase in AKI risk was higher for NSAIDs used in triple versus dual combinations with renin-angiotensin system inhibitors or diuretics alone (numbers needed to harm for 1 year treatment with NSAID of 158 vs. over 300). AKI risk was highest among users of loop diuretic/aldosterone antagonist combinations, in those over 75 years of age, and in those with renal impairment. Thus, the nephrotoxic potential of both dual and triple combinations of NSAIDs with renin-angiotensin system inhibitors and/or diuretics yields a higher incidence of AKI than previously thought.

  9. Molecule-specific Effects of Angiotensin II–Receptor Blockers Independent of the Renin–Angiotensin System

    Czech Academy of Sciences Publication Activity Database

    Kurtz, T. W.; Pravenec, Michal

    2008-01-01

    Roč. 21, č. 8 (2008), s. 852-859 ISSN 0895-7061 R&D Projects: GA MŠk(CZ) 1M0520; GA MZd(CZ) NR8545 Grant - others:EURATOOLS(XE) LSHG-CT-2005-019015; HHMI(US) 55005624 Institutional research plan: CEZ:AV0Z50110509 Keywords : angiotensin-receptor blockers * cardiovascular protection * renin-angiotensin system Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.122, year: 2008

  10. Polychlorinated biphenyl 126 stimulates basal and inducible aldosterone biosynthesis of human adrenocortical H295R cells

    International Nuclear Information System (INIS)

    Li, L.-A.; Wang, P.-W.; Chang, Louis W.

    2004-01-01

    To understand the effects of polychlorinated biphenyls (PCBs) on adrenal aldosterone biosynthesis, we have performed a systematical study to characterize the corresponding steroidogenic response of human adrenocortical cell line H295R to PCB126 exposure. We found that PCB126 at high concentrations stimulated basal and inducible aldosterone production. The aldosterone induction occurred concomitantly with activation of the CYP11B2 gene. Despite the fact that PCB126 acted in synergy with both potassium and angiotensin II (Ang II) in activation of aldosterone synthesis, PCB126 only modestly increased CYP11B2 mRNA expression in the presence of Ang II contrary to the synergistic transcriptional induction elicited by PCB126 and potassium. This implicated that PCB126 had differential interactions with the potassium and Ang II signaling systems in the regulation of aldosterone biosynthesis. In addition, high concentrations of PCB126 elevated transcriptional expression of the type I Ang II receptor (AT 1 ) and might thus sensitize the cellular Ang II responsiveness in both basal and inducible aldosterone biosynthesis. SF-1 was not involved in the PCB126-induced transcriptional regulation despite its importance in steroidogenic gene activation

  11. The unique response of renin and aldosterone to dietary sodium intervention in sodium sensitivity.

    Science.gov (United States)

    Shin, Sung Joon; Lim, ChiYeon; Oh, Sang Woo; Rhee, Moo-Yong

    2014-06-01

    Sodium sensitivity (SS) is a phenomenon in which significant changes in blood pressure (BP) are observed based on sodium intake. The renin-angiotensin-aldosterone system plays a critical role in sodium handling and hypertension. We identified the specific responses of renin and aldosterone based on dietary sodium intake and revealed the relationship between these hormonal changes and dietary sodium intake in patients with SS. In total, 61 subjects were available to analyze full data including plasma renin activity (PRA) and aldosterone. Participants were given a low-sodium DASH diet (LSD) for 7 days and a high-sodium DASH diet (HSD) for the following 7 days. SS was found in five (14.71%) in normotensives, and 14 (51.85%) in hypertensives. In sodium-resistant (SR) subjects, both PRA and aldosterone decreased significantly after consuming HSD. Moreover, a significant correlation was observed between PRA and aldosterone in SR subjects. In contrast, only hypertensive subjects showed a marked fall in PRA after consuming HSD (1.299 ± 0.904 vs. 0.593 ± 0.479) among SS subjects. This study demonstrated the different responses of renin and aldosterone in SS and SR subjects based on dietary sodium intake whether or not they had hypertension. © The Author(s) 2014.

  12. The renin-angiotensin-aldosterone system in cerebral small vessel disease

    NARCIS (Netherlands)

    Brenner, D.; Labreuche, J.; Pico, F.; Scheltens, P.; Poirier, O.; Cambien, F.; Amarenco, P.

    2008-01-01

    Introduction: Cerebral small vessel disease (SVD) appears on magnetic resonance imaging (MRI) as leukoaraiosis (LA), état criblé (EC), and multiple lacunar infarctions (MLI). Although the pathophysiology of SVD is poorly understood, there is evidence of a genetic contribution. We sought to analyze

  13. Localization of aldosterone and corticosterone in the central nervous system, assessed by quantitative autoradiography

    International Nuclear Information System (INIS)

    Birmingham, M.K.; Sar, M.; Stumpf, W.E.

    1984-01-01

    Nuclear localization of tritiated aldosterone in the CNS was studied in rats by numerical evaluation of silver grains, deposited over neuronal cell nuclei in thaw-mounted autoradiograms, and compared with the localization obtained after prior administration of a 100-fold excess of radioinert aldosterone, corticosterone or 18-hydroxy-11-deoxycorticosterone (18-OH-DOC). Corticosterone and 18-OH-DOC completely prevented nuclear localization in most regions examined. However, in contrast to pretreatment with aldosterone, pretreatment with corticosterone and 18-OH-DOC did not completely prevent the concentration of radioactivity in the cell nuclei of the indusium griseum. Traces of radioactivity were, furthermore, retained in areas CA1 and CA2 and the dentate gyrus in rats exposed to corticosterone, but not to 18-OH-DOC, prior to [ 3 H]aldosterone. A similar profile of silver grain distribution to that noted with aldosterone was found for corticosterone except that with tritiated corticosterone the most intense concentration of radioactivity occurred in hippocampal areas CA1 and CA2 and not in the indusium griseum. The authors conclude that (1) a receptor readily shared by aldosterone, corticosterone, 18-OH-DOC and DOC, but not by dihydrotestosterone, is widely distributed throughout the CNS, (2) a receptor shared by aldosterone and 18-OH-DOC, but not by corticosterone may be present in hippocampal areas CA1 and CA2, (3) that both these as well as the receptor accepting dihydrotestosterone can be located within the same cell

  14. Use of angiotensin II receptor blockers in children- a review of ...

    African Journals Online (AJOL)

    Background: The incidence of hypertension in the pediatric population has been increasing. Childhood blood pressure is predictive of adult BP. The renin angiotensin aldosterone system pathway is important in the mediation of pediatric hypertension. New therapies approved for adults are often used off label in children ...

  15. Aldosterone blood test

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003704.htm Aldosterone blood test To use the sharing features on this page, please enable JavaScript. The aldosterone blood test measures the level of the hormone aldosterone in ...

  16. Angiotensin II and Renal Tubular Ion Transport

    Directory of Open Access Journals (Sweden)

    Patricia Valles

    2005-01-01

    Evidence for the regulation of H+-ATPase activity in vivo and in vitro by trafficking/exocytosis has been provided. An additional level of H+-ATPase regulation via protein synthesis may be important as well. Recently, we have shown that both aldosterone and angiotensin II provide such a mechanism of regulation in vivo at the level of the medullary collecting tubule. Interestingly, in this part of the nephron, the effects of aldosterone and angiotensin II are not sodium dependent, whereas in the cortical collecting duct, both aldosterone and angiotensin II, by contrast, affect H+ secretion by sodium-dependent mechanisms.

  17. The renin-angiotensin system and aging in the kidney

    OpenAIRE

    Yoon, Hye Eun; Choi, Bum Soon

    2014-01-01

    Aging is associated with progressive functional deterioration and structural changes in the kidney. Changes in the activity or responsiveness of the renin-angiotensin system (RAS) occur with aging. RAS changes predispose the elderly to various fluid and electrolyte imbalances as well as acute kidney injury and chronic kidney disease. Among the multiple pathways involved in renal aging, the RAS plays a central role. This review summarizes the association of the RAS with structural and function...

  18. PTH Is a Promising Auxiliary Index for the Clinical Diagnosis of Aldosterone-Producing Adenoma.

    Science.gov (United States)

    Zhang, Lin-Xi; Gu, Wei-Jun; Li, Yi-Jun; Wang, Yang; Wang, Wen-Bo; Wang, An-Ping; Shen, Lei; Zang, Li; Yang, Guo-Qing; Lu, Zhao-Hui; Dou, Jing-Tao; Mu, Yi-Ming

    2016-05-01

    Parathyroid hormone (PTH) stimulates aldosterone secretion in human adrenocortex and is regulated by the renin-angiotensin-aldosterone system. We speculated that measurement of PTH may be a valuable aid in the diagnosis of aldosterone-producing adenoma (APA). To test this hypothesis, we recruited 142 patients with adrenal adenoma, of whom 84 had an APA and 58 had a nonfunctioning adrenal adenoma (NFA). Plasma levels of intact PTH, serum potassium, sodium, calcium, phosphate, 25(OH) vitamin D, plasma aldosterone concentration (PAC), plasma renin activity (PRA), and aldosterone to renin ratio (ARR) were measured in every patient. Computed tomography (CT) scanning of the adrenal gland and adrenal hormone levels was used to evaluate the function of the adrenal adenoma. We also evaluated the impact of renin-angiotensin-aldosterone system (RAAS) components on PTH from the recumbent-upright test in 15 patients with APA and 30 patients with NFA. Compared with NFA, PTH levels were significantly increased in patients with APA, and serum calcium and phosphate were significantly decreased. When position was changed from supine to upright, the variation in PTH levels was significantly higher in APA patients compared with NFA patients. Receiver operator characteristic (ROC) curves identified the Youden index, which corresponded to the best tradeoff of combined marker (ARR and PTH) with a sensitivity and specificity of 89.3% and 93.1%, respectively. The baseline and positional variation of serum PTH levels were significant in APA, thus PTH may be a promising auxiliary index for the clinical diagnosis of APA. © American Journal of Hypertension, Ltd 2015. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Alternative pathways for angiotensin II generation in the cardiovascular system

    Directory of Open Access Journals (Sweden)

    C. Becari

    2011-09-01

    Full Text Available The classical renin-angiotensin system (RAS consists of enzymes and peptides that regulate blood pressure and electrolyte and fluid homeostasis. Angiotensin II (Ang II is one of the most important and extensively studied components of the RAS. The beneficial effects of angiotensin converting enzyme (ACE inhibitors in the treatment of hypertension and heart failure, among other diseases, are well known. However, it has been reported that patients chronically treated with effective doses of these inhibitors do not show suppression of Ang II formation, suggesting the involvement of pathways alternative to ACE in the generation of Ang II. Moreover, the finding that the concentration of Ang II is preserved in the kidney, heart and lungs of mice with an ACE deletion indicates the important role of alternative pathways under basal conditions to maintain the levels of Ang II. Our group has characterized the serine protease elastase-2 as an alternative pathway for Ang II generation from Ang I in rats. A role for elastase-2 in the cardiovascular system was suggested by studies performed in heart and conductance and resistance vessels of normotensive and spontaneously hypertensive rats. This mini-review will highlight the pharmacological aspects of the RAS, emphasizing the role of elastase-2, an alternative pathway for Ang II generation.

  20. Combination inhibition of the renin-angiotensin system: is more better?

    Science.gov (United States)

    Krause, Michelle W; Fonseca, Vivian A; Shah, Sudhir V

    2011-08-01

    Angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers are considered the standard of care for treatment of cardiovascular disease and chronic kidney disease. Combination therapy with both angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers effectively inhibits the renin-angiotensin system as well as potentiates the vasodilatory effects of bradykinin. It has been advocated that this dual blockade approach theoretically should result in improved clinical outcomes in both cardiovascular disease and chronic kidney disease. Clinical trial evidence for the use of combination therapy with angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers in cardiovascular disease has provided conflicting results in hypertension, congestive heart failure, and ischemic heart disease. Clinical trial evidence to support combination therapy with angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers in chronic kidney disease has largely been based on proteinuria reduction as a surrogate marker for clinically meaningful outcomes. Recent large-scale randomized clinical trials have not been able to validate protection in halting progression in chronic kidney disease with a dual blockade approach. This review serves as an appraisal on the clinical evidence of combination angiotensin-converting enzyme inhibition and angiotensin II receptor blockade in both cardiovascular disease and chronic kidney disease.

  1. Mutual effects of melatonin and activin on induction of aldosterone production by human adrenocortical cells.

    Science.gov (United States)

    Hara, Takayuki; Otsuka, Fumio; Tsukamoto-Yamauchi, Naoko; Inagaki, Kenichi; Hosoya, Takeshi; Nakamura, Eri; Terasaka, Tomohiro; Komatsubara, Motoshi; Makino, Hirofumi

    2015-08-01

    Melatonin has been reported to suppress adrenocorticotropin (ACTH) secretion in the anterior pituitary and cortisol production in the adrenal by different mechanisms. However, the effect of melatonin on aldosterone production has remained unknown. In this study, we investigated the role of melatonin in the regulation of aldosterone production using human adrenocortical H295R cells by focusing on the activin system expressed in the adrenal. Melatonin receptor MT1 mRNA and protein were expressed in H295R cells and the expression levels of MT1 were increased by activin treatment. Activin increased ACTH-induced, but not angiotensin II (Ang II)-induced, aldosterone production. Melatonin alone did not affect basal synthesis of either aldosterone or cortisol. However, melatonin effectively enhanced aldosterone production induced by co-treatment with ACTH and activin, although melatonin had no effect on aldosterone production induced by Ang II in combination with activin. These changes in steroidogenesis became apparent when the steroid production was evaluated by the ratio of aldosterone/cortisol. Melatonin also enhanced dibutyryl-AMP-induced aldosterone/cortisol levels in the presence of activin, suggesting a functional link to the cAMP-PKA pathway for induction of aldosterone production by melatonin and activin. In accordance with the data for steroids, ACTH-induced, but not Ang II-induced, cAMP synthesis was also amplified by co-treatment with melatonin and activin. Furthermore, the ratio of ACTH-induced mRNA level of CYP11B2 compared with that of CYP17 was amplified in the condition of treatment with both melatonin and activin. In addition, melatonin increased expression of the activin type-I receptor ALK-4 but suppressed expression of inhibitory Smads6/7, leading to the enhancement of Smad2 phosphorylation. Collectively, the results showed that melatonin facilitated aldosterone production induced by ACTH and activin via the cAMP-PKA pathway. The results also

  2. Antidiabetic mechanisms of angiotensin-converting enzyme inhibitors and angiotensin II receptor antagonists: beyond the renin-angiotensin system

    Czech Academy of Sciences Publication Activity Database

    Kurtz, T. W.; Pravenec, Michal

    2004-01-01

    Roč. 22, č. 12 (2004), s. 2253-2261 ISSN 0263-6352 R&D Projects: GA ČR GA301/03/0751 Grant - others:HHMI(US) HHMI55000331 Institutional research plan: CEZ:AV0Z5011922 Keywords : angiotensin II receptors * metabolic syndrome * peroxisome proliferator activated receptors Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.871, year: 2004

  3. Characterization of the cardiac renin angiotensin system in oophorectomized and estrogen-replete mRen2.Lewis rats.

    Directory of Open Access Journals (Sweden)

    Hao Wang

    Full Text Available The cardioprotective effects of estrogen are well recognized, but the mechanisms remain poorly understood. Accumulating evidence suggests that the local cardiac renin-angiotensin system (RAS is involved in the development and progression of cardiac hypertrophy, remodeling, and heart failure. Estrogen attenuates the effects of an activated circulating RAS; however, its role in regulating the cardiac RAS is unclear. Bilateral oophorectomy (OVX; n = 17 or sham-operation (Sham; n = 13 was performed in 4-week-old, female mRen2.Lewis rats. At 11 weeks of age, the rats were randomized and received either 17 β-estradiol (E2, 36 µg/pellet, 60-day release, n = 8 or vehicle (OVX-V, n = 9 for 4 weeks. The rats were sacrificed, and blood and hearts were used to determine protein and/or gene expression of circulating and tissue RAS components. E2 treatment minimized the rise in circulating angiotensin (Ang II and aldosterone produced by loss of ovarian estrogens. Chronic E2 also attenuated OVX-associated increases in cardiac Ang II, Ang-(1-7 content, chymase gene expression, and mast cell number. Neither OVX nor OVX+E2 altered cardiac expression or activity of renin, angiotensinogen, angiotensin-converting enzyme (ACE, and Ang II type 1 receptor (AT1R. E2 treatment in OVX rats significantly decreased gene expression of MMP-9, ACE2, and Ang-(1-7 mas receptor, in comparison to sham-operated and OVX littermates. E2 treatment appears to inhibit upsurges in cardiac Ang II expression in the OVX-mRen2 rat, possibly by reducing chymase-dependent Ang II formation. Further studies are warranted to determine whether an E2-mediated reduction in cardiac chymase directly contributes to this response in OVX rats.

  4. The importance of the renin-angiotensin system in normal cardiovascular homeostasis

    Science.gov (United States)

    Haber, E.

    1975-01-01

    Studies were carried out on adult mongrel dogs (20 to 30 kilograms) to investigate the importance of the renin-angiotensin system. Results indicate that the renin-angiotensin system plays a major role in the maintenance of circulatory homeostasis when extracellular fluid volume is depleted. It was also found that angiotensin II concentration, in addition to renal perfusion pressure, is a factor in the regulation of renin release.

  5. Responses to dehydration in the one-humped camel and effects of blocking the renin-angiotensin system.

    Directory of Open Access Journals (Sweden)

    Mahmoud Alhaj Ali

    Full Text Available Our objectives were to compare the levels of circulating electrolytes, hormones, and renal function during 20 days of dehydration in camels versus the level in non-dehydrated camels and to record the effect of blocking angiotensin II AT1 receptors with losartan during dehydration. Dehydration induced significant increments in serum sodium, creatinine, urea, a substantial fall in body weight, and a doubling in plasma arginine vasopressin (AVP levels. Plasma aldosterone, however, was unaltered compared with time-matched controls. Losartan significantly enhanced the effect of dehydration to reduce body weight and increase serum levels of creatinine and urea, whilst also impairing the rise in plasma AVP and reducing aldosterone levels. We conclude that dehydration in the camel induces substantial increments in serum sodium, creatinine, urea and AVP levels; that aldosterone levels are altered little by dehydration; that blockade of angiotensin II type 1 receptors enhances the dehydration-induced fall in body weight and increase in serum creatinine and urea levels whilst reducing aldosterone and attenuating the rise in plasma AVP.

  6. Renin angiotensin system and gender differences in dopaminergic degeneration

    Directory of Open Access Journals (Sweden)

    Rodriguez-Perez Ana I

    2011-08-01

    Full Text Available Abstract Background There are sex differences in dopaminergic degeneration. Men are approximately two times as likely as premenopausal women of the same age to develop Parkinson's disease (PD. It has been shown that the local renin angiotensin system (RAS plays a prominent role in sex differences in the development of chronic renal and cardiovascular diseases, and there is a local RAS in the substantia nigra and dopaminergic cell loss is enhanced by angiotensin via type 1 (AT1 receptors. Results In the present study, we observed that intrastriatal injection of 6-hydroxydopamine induced a marked loss of dopaminergic neurons in the substantia nigra of male rats, which was significantly higher than the loss induced in ovariectomized female rats given estrogen implants (i.e. rats with estrogen. However, the loss of dopaminergic neurons was significantly lower in male rats treated with the AT1 antagonist candesartan, and similar to that observed in female rats with estrogen. The involvement of the RAS in gender differences in dopaminergic degeneration was confirmed with AT1a-null mice lesioned with the dopaminergic neurotoxin MPTP. Significantly higher expression of AT1 receptors, angiotensin converting enzyme activity, and NADPH-oxidase complex activity, and much lower levels of AT2 receptors were observed in male rats than in female rats with estrogen. Conclusions The results suggest that brain RAS plays a major role in the increased risk of developing PD in men, and that manipulation of brain RAS may be an efficient approach for neuroprotective treatment of PD in men, without the feminizing effects of estrogen.

  7. Relationships between blood pressure and plasma renin, aldosterone and dopamine-beta--hydroxylase in the elderly. Studies in patients over 70 years of age.

    Science.gov (United States)

    Annat, G; Vincent, M; Tourniaire, A; Sassard, J

    1981-01-01

    Plasma renin activity (PRA), aldosterone (PA) and dopamine-beta-hydroxylase activity (DBH) were measured in 49 subjects over 70 years of age, selected for normal or high blood pressure level. By comparison with younger controls, elderly subjects exhibited lower supine or upright PRA, but similar PA and DBH. No relationship could be found between individual blood pressure, and PRA, PA or DBH. The data favor the view that the renin-angiotensin-aldosterone system does not play an important causative role in elderly hypertension. They also point to the necessity of age-matched controls when this system is being studied in elderly patients.

  8. Aldosterone as a renal growth factor.

    LENUS (Irish Health Repository)

    Thomas, Warren

    2011-04-05

    Aldosterone regulates blood pressure through its effects on the cardiovascular system and kidney. Aldosterone can also contribute to the development of hypertension that leads to chronic pathologies such as nephropathy and renal fibrosis. Aldosterone directly modulates renal cell proliferation and differentiation as part of normal kidney development. The stimulation of rapidly activated protein kinase cascades is one facet of how aldosterone regulates renal cell growth. These cascades may also contribute to myofibroblastic transformation and cell proliferation observed in pathological conditions of the kidney. Polycystic kidney disease is a genetic disorder that is accelerated by hypertension. EGFR-dependent proliferation of the renal epithelium is a factor in cyst development and trans-activation of EGFR is a key feature in initiating aldosterone-induced signalling cascades. Delineating the components of aldosterone-induced signalling cascades may identify novel therapeutic targets for proliferative diseases of the kidney.

  9. The adipose renin-angiotensin system modulates sysemic markers of insulin sensitivity activates the intrarenal renin-angiotensin system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Suyeon [University of Tennessee, Knoxville (UTK); Soltani-Bejnood, Morvarid [University of Tennessee, Knoxville (UTK); Quignard-Boulange, Annie [Centre Biomedical des Cordeliers, Paris, France; Massiera, Florence [Centre de Biochimie, Nice, France; Teboul, Michele [Centre de Biochimie, Nice, France; Ailhaud, Gerard [Centre de Biochimie, Nice, France; Kim, Jung [University of Tennessee, Knoxville (UTK); Moustaid-Moussa, Naima [University of Tennessee, Knoxville (UTK); Voy, Brynn H [ORNL

    2006-07-01

    BACKGROUND: A growing body of data provides increasing evidence that the adipose tissue renin-angiotensin system (RAS) contributes to regulation of fat mass. Beyond its paracrine actions within adipose tissue, adipocyte-derived angiotensin II (Ang II) may also impact systemic functions such as blood pressure and metabolism. METHODS AND RESULTS: We used a genetic approach to manipulate adipose RAS activity in mice and then study the consequences on metabolic parameters and on feedback regulation of the RAS. The models included deletion of the angiotensinogen (Agt) gene (Agt-KO), its expression solely in adipose tissue under the control of an adipocyte-specific promoter (aP2-Agt/ Agt-KO), and overexpression in adipose tissue of wild type mice (aP2-Agt). Total body weight, epididymal fat pad weight, and circulating levels of leptin, insulin and resistin were significantly decreased in Agt-KO mice, while plasma adiponectin levels were increased. Overexpression of Agt in adipose tissue resulted in increased adiposity and plasma leptin and insulin levels compared to wild type (WT) controls. Angiotensinogen and type I Ang II receptor protein levels were also markedly elevated in kidney of aP2-Agt mice, suggesting that hypertension in these animals may be in part due to stimulation of the intrarenal RAS. CONCLUSIONS: Taken together, the results from this study demonstrate that alterations in adipose RAS activity significantly alter both local and systemic physiology in a way that may contribute to the detrimental health effects of obesity.

  10. Renin-angiotensin system gene expression and neurodegenerative diseases.

    Science.gov (United States)

    Goldstein, Benjamin; Speth, Robert C; Trivedi, Malav

    2016-07-01

    Single nucleotide polymorphisms and altered gene expression of components of the renin-angiotensin system (RAS) are associated with neurodegenerative diseases. Drugs that interact with the RAS have been shown to affect the course of neurodegenerative disease, suggesting that abnormalities in the RAS may contribute to neurodegenerative disease. A meta-analysis of genome-wide association studies and gene expression data for 14 RAS-related proteins was carried out for five neurodegenerative diseases: Alzheimer's disease, Parkinson's disease, narcolepsy, amyotrophic lateral sclerosis and multiple sclerosis. No single nucleotide polymorphisms in any of the 14 RAS-related protein genes were significantly associated with the five neurodegenerative diseases investigated. There was an inverse association between expression of ATP6AP2, which encodes the (pro)renin receptor, and multiple sclerosis, Alzheimer's disease and Parkinson's disease. An association of AGTR, which encodes the AT1 angiotensin II receptor, and Parkinson's disease and Alzheimer's disease was also observed. To date, no single nucleotide polymorphisms in components of the RAS can be definitively linked to the neurodegenerative diseases evaluated in this study. However, altered gene expression of several components of the RAS is associated with several neurodegenerative diseases, which may indicate that the RAS contributes to the pathology of these diseases. © The Author(s) 2016.

  11. Renin-angiotensin system activity in vitamin D deficient, obese individuals with hypertension: An urban Indian study

    Directory of Open Access Journals (Sweden)

    Sunil Kumar Kota

    2011-01-01

    Full Text Available Background: Elevated renin-angiotensin-aldosterone system (RAAS activity is an important mechanism in the development of hypertension. Both obesity and 25-hydroxy vitamin D [25(OHD] deficiency have been associated with hypertension and augmented renin-angiotensin system (RAS activity. We tried to test the hypothesis that vitamin D deficiency and obesity are associated with increased RAS activity in Indian patients with hypertension. Materials and Methods: Fifty newly detected hypertensive patients were screened. Patients with secondary hypertension, chronic kidney disease, or coronary artery disease were excluded. Patients underwent measurement of vitamin D and plasma renin and plasma aldosterone concentrations. They were divided into three groups according to their baseline body mass index (BMI; normal <25 kg/m 2 , overweight 25-29.9 kg/m 2 and obese ≥30 kg/m 2 and 25(OHD levels (deficient <20 ng/ml, insufficient 20-29 ng/ml and optimal ≥30 ng/ml. Results: A total of 50 (male:female = 32:18 patients were included, with a mean age of 49.5 ± 7.8 years, mean BMI of 28.3 ± 3.4 kg/m 2 and a mean 25(OHD concentration of 18.5 ± 6.4 ng/ml. Mean systolic blood pressure (SBP was 162.4 ± 20.2 mm Hg and mean diastolic blood pressure (DBP was 100.2 ± 11.2 mm Hg. All the three blood pressure parameters [SBP, DBP and mean arterial pressure (MAP] were significantly higher among individuals with lower 25(OHD levels. The P values for trends in SBP, DBP and MAP were 0.009, 0.01 and 0.007, respectively. Though all the three blood pressure parameters (SBP, DBP and MAP were higher among individuals with higher BMIs, they were not achieving statistical significance. Increasing trends in PRA and PAC were noticed with lower 25(OHD and higher BMI levels. Conclusion: Vitamin D deficiency and obesity are associated with stimulation of RAAS activity. Vitamin D supplementation along with weight loss may be studied as a therapeutic strategy to reduce tissue RAS

  12. Dual angiotensin receptor and neprilysin inhibition as an alternative to angiotensin-converting enzyme inhibition in patients with chronic systolic heart failure: rationale for and design of the Prospective comparison of ARNI with ACEI to Determine Impact on Global Mortality and morbidity in Heart Failure trial (PARADIGM-HF)

    NARCIS (Netherlands)

    McMurray, J.J.; Packer, M.; Desai, A.S.; Gong, J.; Lefkowitz, M.P.; Rizkala, A.R.; Rouleau, J.; Shi, V.C.; Solomon, S.D.; Swedberg, K.; Zile, M.R.; Bellersen, L.; et al.,

    2013-01-01

    AIMS: Although the focus of therapeutic intervention has been on neurohormonal pathways thought to be harmful in heart failure (HF), such as the renin-angiotensin-aldosterone system (RAAS), potentially beneficial counter-regulatory systems are also active in HF. These promote vasodilatation and

  13. The renin-angiotensin system and aging in the kidney.

    Science.gov (United States)

    Yoon, Hye Eun; Choi, Bum Soon

    2014-05-01

    Aging is associated with progressive functional deterioration and structural changes in the kidney. Changes in the activity or responsiveness of the renin-angiotensin system (RAS) occur with aging. RAS changes predispose the elderly to various fluid and electrolyte imbalances as well as acute kidney injury and chronic kidney disease. Among the multiple pathways involved in renal aging, the RAS plays a central role. This review summarizes the association of the RAS with structural and functional changes in the aging kidney and age-related renal injury, and describes the underlying mechanisms of RAS-related renal aging. An improved understanding of the renal aging process may lead to better individualized care of the elderly and improved renal survival in age-related diseases.

  14. Involvement of Renin-Angiotensin System in Damage of Angiotensin-Converting Enzyme Inhibitor Captopril on Bone of Normal Mice.

    Science.gov (United States)

    Liu, Jin-Xin; Wang, Liang; Zhang, Yan

    2015-01-01

    This study was performed to investigate the effect of angiotensin-converting enzyme inhibitor, captopril, on bone metabolism and histology, and the action of captopril on the components of the skeletal renin-angiotensin system (RAS) and bradykinin receptor in normal male mice. The mice were orally administered captopril (10 mg/kg) for 4 weeks with vehicle-treated mice as normal control. The histology of trabecular bone at the distal femoral end was determined by hematoxylin & eosin, Safranin O and Masson-Trichrome staining. The captopril-treated mice showed a decreased level of testosterone (pCaptopril has detrimental effects on trabecular bone as demonstrated by the loss of cancellous bone mass and network connections as well as changes to the chondrocytes zone. The expression of angiotensin-converting enzyme (pcaptopril treatment. Thus, the potential underlying mechanism of the damage of captopril on bone can be attributed the increased activity of local bone RAS and the activation of bradykinin receptor.

  15. Paradoxic activation of the renin-angiotensin system in twin-twin transfusion syndrome: an explanation for cardiovascular disturbances in the recipient.

    Science.gov (United States)

    Mahieu-Caputo, Dominique; Meulemans, Alain; Martinovic, Jelena; Gubler, Marie-Claire; Delezoide, Anne-Lise; Muller, Françoise; Madelenat, Patrick; Fisk, Nicholas M; Dommergues, Marc

    2005-10-01

    Despite advances in treatment, twin-to-twin transfusion syndrome (TTTS) still carries a high risk for perinatal mortality and morbidity. Simple blood transfer from the donor to the recipient twin cannot explain all of the features of this disease, in particular the recipient's hypertensive cardiomyopathy. We report a case in which TTTS resulted in preterm delivery with early neonatal death of both twins, allowing assessment of the renin angiotensin system (RAS) status of each fetus, both by cord blood renin and aldosterone assay and by renal immunohistochemistry. The donor had severe oliguria/oligohydramnios, whereas the recipient, in addition to severe polyuria/polyhydramnios, had cardiomyopathy, atrioventricular regurgitation, and ascites. Although immunohistochemistry demonstrated that renal secretion of renin was up-regulated in the donor and down-regulated in the recipient, cord blood levels of renin and aldosterone were similar, with high renin levels in both twins. This observation supports the hypothesis that despite renal RAS down-regulation, the recipient is exposed to RAS effectors elaborated in the donor and transferred via placental shunts. This may contribute to cardiomyopathy and hypertension in the recipient, which cannot be accounted for by hypervolemia alone. We thus hypothesized that in TTTS, the recipient's hypertensive cardiomyopathy could be due to a mechanism similar to the classical model of hypertension referred to as "2 kidneys-1 clip." Thus the hypovolemic donor twin, comparable to the clipped kidney, produces vasoactive hormones that compromise the recipient, comparable to the normal kidney, causing hypertension and cardiomyopathy.

  16. Effects of dual renin-angiotensin system blockade on proteinuria in a ...

    African Journals Online (AJOL)

    Kidney diseases manifesting as proteinuria or elevated creatinine are increasingly prevalent complications of HIV infection. We report the effects of dual renin-angiotensin system blockade on proteinuria in a hypertensive black African HIV-infected patient.

  17. Renin angiotensin system and cardiac hypertrophy after sinoaortic denervation in rats

    Directory of Open Access Journals (Sweden)

    Aline Cristina Piratello

    2010-01-01

    Full Text Available OBJECTIVE: The aim of this study was to evaluate the role of angiotensin I, II and 1-7 on left ventricular hypertrophy of Wistar and spontaneously hypertensive rats submitted to sinoaortic denervation. METHODS: Ten weeks after sinoaortic denervation, hemodynamic and morphofunctional parameters were analyzed, and the left ventricle was dissected for biochemical analyses. RESULTS: Hypertensive groups (controls and denervated showed an increase on mean blood pressure compared with normotensive ones (controls and denervated. Blood pressure variability was higher in denervated groups than in their respective controls. Left ventricular mass and collagen content were increased in the normotensive denervated and in both spontaneously hypertensive groups compared with Wistar controls. Both hypertensive groups presented a higher concentration of angiotensin II than Wistar controls, whereas angiotensin 1-7 concentration was decreased in the hypertensive denervated group in relation to the Wistar groups. There was no difference in angiotensin I concentration among groups. CONCLUSION: Our results suggest that not only blood pressure variability and reduced baroreflex sensitivity but also elevated levels of angiotensin II and a reduced concentration of angiotensin 1-7 may contribute to the development of left ventricular hypertrophy. These data indicate that baroreflex dysfunction associated with changes in the renin angiotensin system may be predictive factors of left ventricular hypertrophy and cardiac failure.

  18. A Local Inflammatory Renin-Angiotensin System Drives Sensory Axon Sprouting in Provoked Vestibulodynia.

    Science.gov (United States)

    Liao, Zhaohui; Chakrabarty, Anuradha; Mu, Ying; Bhattacherjee, Aritra; Goestch, Martha; Leclair, Catherine M; Smith, Peter G

    2017-05-01

    Vestibulodynia is a form of provoked vulvodynia characterized by profound tenderness, hyperinnervation, and frequently inflammation within well-defined areas of the human vestibule. Previous experiments in animal models show that inflammatory hypersensitivity and hyperinnervation occur in concert with establishment of a local renin-angiotensin system (RAS). Moreover, mechanical hypersensitivity and sensory axon sprouting are prevented by blocking effects of angiotensin II on angiotensin II receptor type 2 (AT2) receptors. This case-control study assessed whether a RAS contributes to hyperinnervation observed in human vestibulodynia. Vestibular biopsies from asymptomatic controls or patients' nontender areas showed moderate innervation and small numbers of inflammatory cells. In women with vestibulodynia, tender areas contained increased numbers of mechanoreceptive nociceptor axons, T-cells, macrophages, and B-cells, whereas mast cells were unchanged. RAS proteins were increased because of greater numbers of T cells and B cells expressing angiotensinogen, and increased renin-expressing T cells and macrophages. Chymase, which converts angiotensin I to angiotensin II, was present in constant numbers of mast cells. To determine if tender vestibular tissue generates angiotensin II that promotes axon sprouting, we conditioned culture medium with vestibular tissue. Rat sensory neurons cultured in control-conditioned medium showed normal axon outgrowth, whereas those in tender tissue-conditioned medium showed enhanced sprouting that was prevented by adding an AT2 antagonist or angiotensin II neutralizing antibody. Hypersensitivity in provoked vestibulodynia is therefore characterized by abnormal mechanonociceptor axon proliferation, which is attributable to inflammatory cell-derived angiotensin II (or a closely related peptide) acting on neuronal AT2 receptors. Accordingly, reducing inflammation or blocking AT2 represent rational strategies to mitigate this common pain

  19. Aldosterone and aldosterone receptor antagonists in patients with chronic heart failure

    Directory of Open Access Journals (Sweden)

    Nappi J

    2011-06-01

    associated with systolic heart failure will benefit from the addition of an aldosterone receptor antagonist to the standard therapies of angiotensin-converting enzyme inhibitors and beta-blockers. This review will address the pharmacologic basis of aldosterone receptor antagonists in patients with heart failure and the clinical impact of this therapy.Keywords: aldosterone receptor antagonists, eplerenone, spironolactone, systolic heart failure

  20. Primary Aldosteronism

    Science.gov (United States)

    ... Center Pacientes y Cuidadores Hormones and Health The Endocrine System Hormones Endocrine Disrupting Chemicals (EDCs) Steroid and Hormone ... an Endocrinologist Clinical Trials Hormones and Health The Endocrine System Hormones Endocrine Disrupting Chemicals (EDCs) Steroid and Hormone ...

  1. Elevated N-terminal pro-brain natriuretic peptide levels predict an enhanced anti-hypertensive and anti-proteinuric benefit of dietary sodium restriction and diuretics, but not angiotensin receptor blockade, in proteinuric renal patients

    NARCIS (Netherlands)

    Slagman, Maartje C. J.; Waanders, Femke; Vogt, Liffert; Damman, Kevin; Hemmelder, Marc; Navis, Gerjan; Laverman, Gozewijn D.

    2012-01-01

    Background. Renin angiotensin aldosterone system (RAAS) blockade only partly reduces blood pressure, proteinuria and renal and cardiovascular risk in chronic kidney disease (CKD) but often requires sodium targeting [i.e. low sodium diet (LS) and/or diuretics] for optimal efficacy. However, both

  2. Elevated N-terminal pro-brain natriuretic peptide levels predict an enhanced anti-hypertensive and anti-proteinuric benefit of dietary sodium restriction and diuretics, but not angiotensin receptor blockade, in proteinuric renal patients

    NARCIS (Netherlands)

    Slagman, Maartje C. J.; Waanders, Femke; Vogt, Liffert; Damman, Kevin; Hemmelder, Marc; Navis, Gerjan; Laverman, Gozewijn D.

    Background. Renin angiotensin aldosterone system (RAAS) blockade only partly reduces blood pressure, proteinuria and renal and cardiovascular risk in chronic kidney disease (CKD) but often requires sodium targeting [i.e. low sodium diet (LS) and/or diuretics] for optimal efficacy. However, both

  3. Aldosterone breakthrough in dogs with naturally occurring myxomatous mitral valve disease.

    Science.gov (United States)

    Ames, M K; Atkins, C E; Eriksson, A; Hess, A M

    2017-06-01

    Aldosterone breakthrough (ABT) is the condition in which angiotensin converting enzyme inhibitors (ACEIs) and/or angiotensin receptor blockers fail to effectively suppress the activity of the renin angiotensin aldosterone system. The objective of this study was to determine if ABT occurs in dogs with naturally occurring myxomatous mitral valve disease receiving an ACEI, using the urine aldosterone to creatinine ratio (UAldo:C) as a measure of renin angiotensin aldosterone system activation. This study includes 39 dogs with myxomatous mitral valve disease. A UAldo:C cut-off definition (derived from a normal population of healthy, adult, and client-owned dogs) was used to determine the prevalence of ABT in this population. Spearman analysis and univariate logistic regression were used to evaluate the relationship between UAldo:C and ABT (yes/no) and eight variables (age, serum K + concentration, serum creatinine concentration, ACEI therapy duration and ACEI dosage, furosemide therapy duration and furosemide dosage, and urine sample storage time). Finally, the UAldo:C in dogs receiving spironolactone, as part congestive heart failure (CHF) therapy, was compared to dogs with CHF that were not receiving spironolactone. The prevalence of ABT was 32% in dogs with CHF and 30% in dogs without CHF. There was no relationship between either the UAldo:C or the likelihood of ABT and the eight variables. Therapy with spironolactone lead to a significant elevation of the UAldo:C. Using the UAldo:C and a relatively stringent definition of ABT, it appears that incomplete RAAS blockade is common in dogs with MMVD receiving an ACEI. The prevalence of ABT in this canine population mirrors that reported in humans. While the mechanism of ABT is likely multifactorial and still poorly understood, the proven existence of ABT in dogs offers the potential to improve the prognosis for MMVD with the addition of a mineralocorticoid receptor blocker to current therapeutic regimens

  4. Reduced glomerular angiotensin II receptor density in diabetes mellitus in the rat: time course and mechanism

    International Nuclear Information System (INIS)

    Wilkes, B.M.

    1987-01-01

    Glomerular angiotensin II receptors are reduced in number in early diabetes mellitus, which may contribute to hyperfiltration and glomerular injury. The time course and role of the renin-angiotensin-aldosterone system in the pathogenesis of the receptor abnormality were studied in male Sprague-Dawley rats made diabetic with streptozotocin (65 mg, iv). Glomerular angiotensin II receptors were measured by Scatchard analysis; insulin, renin activity, angiotensin II, and aldosterone were measured by RIA. Diabetes mellitus was documented at 24 h by a rise in plasma glucose (vehicle-injected control, 133 +/- 4; diabetic, 482 +/- 22 mg/dl and a fall in plasma insulin (control, 53.1 +/- 5.7; diabetic, 35.6 +/- 4.0 microIU/ml. At 24 h glomerular angiotensin II receptor density was decreased by 26.5% in diabetic rats (control, 75.5 +/- 9.6 X 10(6); diabetic, 55.5 +/- 8.3 X 10(6) receptors/glomerulus. Receptor occupancy could not explain the defect, because there was reduced binding in diabetic glomeruli after pretreatment with 3 M MgCl 2 , a maneuver that caused dissociation of previously bound hormone. There was a progressive return of the receptor density toward normal over the 60 days following induction of diabetes, with diabetic glomeruli measuring 22.7%, 14.8%, and 3.7% fewer receptors than age-matched controls at 11 days, 1 month, and 2 months, respectively

  5. Mild hyperparathyroidism: a novel surgically correctable feature of primary aldosteronism.

    Science.gov (United States)

    Maniero, Carmela; Fassina, Ambrogio; Seccia, Teresa M; Toniato, Antonio; Iacobone, Maurizio; Plebani, Mario; De Caro, Raffaele; Calò, Lorenzo A; Pessina, Achille C; Rossi, Gian P

    2012-02-01

    The parathyroid hormone (PTH) stimulates aldosterone secretion and cell proliferation in human adrenocortical cells; moreover, in rats hyperaldosteronism was associated with hyperparathyroidism. Hence, PTH could drive aldosterone excess in human primary aldosteronism. To test this hypothesis, we recruited 105 consecutive hypertensive patients, of whom 44 had primary aldosteronism due to an aldosterone-producing adenoma (APA) and 61 had primary (essential) hypertension. We measured the plasma levels of (1-84)-PTH, 25(OH)D, 1,25(OH)2D, and serum Ca (total and ionized), inorganic P, Mg, K, and the 24-h urinary excretion of Ca, P, and deoxypyridinoline. In primary aldosteronism patients, these measurements were repeated after adrenalectomy or mineralocorticoid receptor blockade. We also sought for PTH receptor (PTHR-1) mRNA and protein in APA tissue. Compared with primary (essential) hypertension patients, those with primary aldosteronism showed significantly higher plasma PTH (+31%), despite comparable urinary Ca excretion and similarly deficient 25(OH) vitamin D levels. In APA patients, who showed the PTHR-1 transcript and protein in tumor tissue, adrenalectomy normalized PTH levels (from 118 ± 13 to 76 ± 12 ng/l; P = 0.002) and increased ionized Ca(from 1.17 ± 0.04 to 1.22 ± 0.03 mmol/l; P hyperparathyroidism by acting on PTHR-1 in APA might contribute to maintaining hyperaldosteronism despite suppression of angiotensin II formation.

  6. Effect of chronic oral administration of a low dose of captopril on sodium appetite of hypothyroid rats: Influence of aldosterone treatment

    Directory of Open Access Journals (Sweden)

    Ventura R.R.

    2001-01-01

    Full Text Available Rats rendered hypothyroid by treatment with methimazole develop an exaggerated sodium appetite. We investigated here the capacity of hypothyroid rats (N = 12 for each group to respond to a low dose of captopril added to the ration, a paradigm which induces an increase in angiotensin II synthesis in cerebral areas that regulate sodium appetite by increasing the availability of circulating angiotensin I. In addition, we determined the influence of aldosterone in hypothyroid rats during the expression of spontaneous sodium appetite and after captopril treatment. Captopril significantly increased (P<0.05 the daily intake of 1.8% NaCl (in ml/100 g body weight in hypothyroid rats after 36 days of methimazole administration (day 36: 9.2 ± 0.7 vs day 32: 2.8 ± 0.6 ml, on the 4th day after captopril treatment. After the discontinuation of captopril treatment, daily 1.8% NaCl intake reached values ranging from 10.0 ± 0.9 to 13.9 ± 1.0 ml, 48 to 60 days after treatment with methimazole. Aldosterone treatment significantly reduced (P<0.05 saline intake before (7.3 ± 1.6 vs day 0, 14.4 ± 1.3 ml and after captopril treatment. Our results demonstrate that, although hypothyroid rats develop a deficiency in the production of all components of the renin-angiotensin-aldosterone system, their capacity to synthesize angiotensin II at the cerebral level is preserved. The partial reversal of daily 1.8% NaCl intake during aldosterone treatment suggests that sodium retention reduces both spontaneous and captopril-induced salt appetite.

  7. Pharmacological treatment of aldosterone excess

    NARCIS (Netherlands)

    Deinum, J.; Riksen, N.P.; Lenders, J.W.M.

    2015-01-01

    Primary aldosteronism, caused by autonomous secretion of aldosterone by the adrenals, is estimated to account for at least 5% of hypertension cases. Hypertension explains the considerable cardiovascular morbidity caused by aldosteronism only partly, calling for specific anti-aldosterone drugs. The

  8. The renin angiotensin system in the development of cardiovascular disease: role of aliskiren in risk reduction

    Directory of Open Access Journals (Sweden)

    Paolo Verdecchia

    2008-10-01

    Full Text Available Paolo Verdecchia1, Fabio Angeli1, Giovanni Mazzotta1, Giorgio Gentile2, Gianpaolo Reboldi21Department of Cardiology, Clinical Research Unit ‘Preventive Cardiology’, Hospital ‘Santa Maria della Misericordia’, and Fondazione Umbra Cuore e Ipertensione – AUCI Onlus, Perugia, Italy; 2Department of Internal Medicine University of Perugia, ItalyAbstract: An association has been shown between plasma renin activity (PRA and the risk of cardiovascular disease. There is also evidence that angiotensin II exerts detrimental effects on progression and instabilization of atherosclerotic plaque. The renin-angiotensin system (RAS can be inhibited through inhibition of angiotensin I (Ang I generation from angiotensinogen by direct renin inhibitors, inhibition of angiotensin II (Ang II generation from angiotensin I by angiotensin-converting enzyme inhibitors and finally by direct inhibition of the action of Ang II receptor level. Aliskiren, the first direct renin inhibitor to reach the market, is a lowmolecular-weight, orally active, hydrophilic nonpeptide. Aliskiren blocks Ang I generation, while plasma renin concentration increases because the drugs blocks the negative feed-back exerted by Ang II on renin synthesis. Because of its long pharmacological half-life, aliskiren is suitable for once-daily administration. Its through-to-peak ratio approximates 98% for the 300 mg/day dose. Because of its mechanism of action, aliskiren might offer the additional opportunity to inhibit progression of atherosclerosis at tissue level. Hypertension is an approved indication for this drug, which is also promising for the treatment of heart failure. The efficacy of this drug in reducing major clinical events is being tested in large ongoing clinical trials.Keywords: plasma renin activity, renin angiotensin system, aliskiren, angiotensinogen, renin, hypertension, heart failure, diabetes

  9. From preeclampsia to renal disease : a role of angiogenic factors and the renin-angiotensin aldosterone system?

    NARCIS (Netherlands)

    van der Graaf, Anne Marijn; Toering, Tsjitske J.; Faas, Marijke M.; Lely, A. Titia

    2012-01-01

    Complicating up to 8% of pregnancies, preeclampsia is the most common glomerular disease worldwide and remains a leading cause of infant and maternal morbidity and mortality. Although the exact pathogenesis of this syndrome of hypertension and proteinuria is still incomplete, a consistent line of

  10. Determinants of the renin-angiotensin-aldosterone system in cirrhosis with special emphasis on the central blood volume

    DEFF Research Database (Denmark)

    Møller, Søren; Bendtsen, Flemming; Henriksen, Jens H

    2006-01-01

    of the RAAS and its potential determinants with special focus on the central and arterial blood volume (CBV). MATERIAL AND METHODS: Eighty-nine patients (Child class A/B/C: 19/41/29) and 32 controls were included in the study. All were given a haemodynamic examination with measurement of determinants...

  11. Cardiovascular effects of the angiotensin type 2 receptor.

    Science.gov (United States)

    Faria-Costa, Gabriel; Leite-Moreira, Adelino; Henriques-Coelho, Tiago

    2014-01-01

    The angiotensin type 2 receptor, AT2R, has been described as having opposite effects to the angiotensin type 1 receptor, AT1R. Although the quantities of the AT2R found in the adult are low, its expression rises in pathological situations. The AT2R has three major signaling pathways: activation of serine/threonine phosphatases (promoting apoptosis and antioxidant effects), activation of the bradykinin/NO/cGMP pathway (promoting vasodilation), and activation of phospholipase A2 (associated with regulation of potassium currents). The AT2R appears to have effects in vascular remodeling, atherosclerosis prevention and blood pressure lowering (when associated with an AT1R inhibitor). After myocardial infarction, the AT2R appears to decrease infarct size, cardiac hypertrophy and fibrosis, and to improve cardiac function. However, its role in the heart is controversial. In the kidney, the AT2R promotes natriuresis. Until now, treatment directed at the renin-angiotensin-aldosterone system has been based on angiotensin-converting enzyme inhibitors or angiotensin type 1 receptor blockers. The study of the AT2R has been revolutionized by the discovery of a direct agonist, C21, which promises to become part of the treatment of cardiovascular disease. Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  12. The Impact of Age-Related Dysregulation of the Angiotensin System on Mitochondrial Redox Balance

    Directory of Open Access Journals (Sweden)

    Ramya eVajapey

    2014-11-01

    Full Text Available Aging is associated with the accumulation of various deleterious changes in cells. According to the free radical and mitochondrial theory of aging, mitochondria initiate most of the deleterious changes in aging and govern life span. The failure of mitochondrial reduction-oxidation (redox homeostasis and the formation of excessive free radicals are tightly linked to dysregulation in the Renin Angiotensin System (RAS. A main rate-controlling step in RAS is renin, an enzyme that hydrolyzes angiotensinogen to generate angiotensin I. Angiotensin I is further converted to Angiotensin II (Ang II by angiotensin-converting enzyme (ACE. Ang II binds with equal affinity to two main angiotensin receptors—type 1 (AT1R and type 2 (AT2R. The binding of Ang II to AT1R activates NADPH oxidase, which leads to increased generation of cytoplasmic reactive oxygen species (ROS. This Ang II-AT1R–NADPH-ROS signal triggers the opening of mitochondrial KATP channels and mitochondrial ROS production in a positive feedback loop. Furthermore, RAS has been implicated in the decrease of many of ROS scavenging enzymes, thereby leading to detrimental levels of free radicals in the cell.AT2R is less understood, but evidence supports an anti-oxidative and mitochondria-protective function for AT2R. The overlap between age related changes in RAS and mitochondria, and the consequences of this overlap on age-related diseases are quite complex. RAS dysregulation has been implicated in many pathological conditions due to its contribution to mitochondrial dysfunction. Decreased age-related, renal and cardiac mitochondrial dysfunction was seen in patients treated with angiotensin receptor blockers. The aim of this review is to: (a report the most recent information elucidating the role of RAS in mitochondrial redox hemostasis and (b discuss the effect of age-related activation of RAS on generation of free radicals.

  13. Diurnal variation of aldosterone and plasma renin activity: timing relation to melatonin and cortisol and consistency after prolonged bed rest.

    Science.gov (United States)

    Hurwitz, Shelley; Cohen, Richard J; Williams, Gordon H

    2004-04-01

    Exposure to prolonged bed rest is known to induce changes in the renin-angiotensin-aldosterone system (RAAS) by way of posture, sodium and potassium balance, and stress, which may have serious consequences for patients. We focused on the diurnal variation of the RAAS by investigating changes in the levels of plasma renin activity (PRA) and aldosterone; for comparison to markers of the intrinsic pacemaker and to stress, we measured melatonin and cortisol. PRA, aldosterone, melatonin, and cortisol were measured hourly in 10 normal subjects with standardized sleep patterns, posture, and diet at baseline and after 11 days of prolonged bed rest conducted under a light-dark cycle. Circadian characteristics of hormone secretion patterns were estimated by multiple harmonic regression with excellent goodness-of-fit measures. Variability in the melatonin and cortisol patterns across subjects was minimal. Even for pulsatile hormones, this technique successfully estimated the acrophase, which was the salient feature. Baseline hormone peak times started with melatonin near the middle of the sleep period, followed by PRA, then aldosterone, and then cortisol around wake time. Prolonged bed rest did not induce significant changes in any timing characteristic of the secretion patterns. Baseline and prolonged bed rest peak times for melatonin and cortisol and amplitude characteristics for all hormones were highly correlated, indicating consistency within individuals. These data provide strong evidence that prolonged bed rest of 11 days' duration does not disrupt either the timing characteristics of the RAAS or the intrinsic pacemaker.

  14. Regulation of the renin–angiotensin system in coronary atherosclerosis: A review of the literature

    Directory of Open Access Journals (Sweden)

    Ramadan A Hammoud

    2008-01-01

    Full Text Available Ramadan A Hammoud, Christopher S Vaccari, Sameer H Nagamia, Bobby V KhanEmory University School of Medicine, Division of Cardiology, Grady Memorial Hospital Vascular Research Laboratory, Atlanta, Georgia, USAAbstract: Activation of the renin–angiotensin system (RAS is significant in the pathogenesis of cardiovascular disease and specifically coronary atherosclerosis. There is strong evidence that the RAS has effects on the mechanisms of action of atherosclerosis, including fibrinolytic balance, endothelial function, and plaque stability. Pharmacological inhibition of the renin angiotensin system includes angiotensin converting enzyme (ACE inhibitors, angiotensin receptor blockers (ARBs, and renin inhibitors. These agents have clinical benefits in reducing morbidity and mortality in the management of hypertension. In addition, ACE inhibitors and ARBs have shown to be effective in the management of congestive heart failure and acute myocardial infarction. This review article discusses the biochemical and molecular mechanisms involving the RAS in coronary atherosclerosis as well as the effects of RAS inhibition in clinical studies involving coronary atherosclerosis.Keywords: angiotensin II, atherosclerosis, endothelium, inflammation, vasculature

  15. Prothrombotic aldosterone action – a new side of the hormone

    Directory of Open Access Journals (Sweden)

    Anna Gromotowicz

    2010-10-01

    Full Text Available Recent studies have focused on a new wave of interest in aldosterone due mainly to its growing profile as a local messenger in pathology of the cardiovascular system, rather than its hormonal action. In the last few years strong evidence for a correlation between raised aldosterone level and haemostasis disturbances leading to increased risk of cardiovascular events has been provided. It has been demonstrated that aldosterone contributes to endothelial dysfunction, fibrinolytic disorders and oxidative stress augmentation. It was also shown that chronic aldosterone treatment results in enhanced experimental arterial thrombosis. Our study in a venous model of thrombosis in normotensive rats confirmed that even a short-lasting increase in aldosterone level intensified thrombus formation. One-hour aldosterone infusion shortened bleeding time; increased platelet adhesion to collagen; reduced tissue factor, thrombin activatable fibrinolysis inhibitor, and plasminogen activator inhibitor; and increased plasminogen activator plasma level. A fall in plasma nitric oxide metabolite concentration with a decrease in aortic nitric oxide synthase mRNA level was also observed. Moreover, aldosterone increased hydrogen peroxide and malonyl dialdehyde plasma concentration and augmented NADPH oxidase and superoxide dismutase aortic expression. Therefore, the mechanism of aldosterone prothrombotic action is multiple and involves primary haemostasis activation, procoagulative and antifibrinolytic action, NO bioavailability impairment and oxidative stress augmentation. The effects of aldosterone were not fully abolished by mineralocorticoid receptor blockade, suggesting the involvement of alternative mechanisms in the prothrombotic aldosterone action.

  16. Genetic variation and activity of the renin-angiotensin system and severe hypoglycemia in type 1 diabetes

    DEFF Research Database (Denmark)

    Pedersen-Bjergaard, Ulrik; Dhamrait, Sukhbir S.; Sethi, Amar A

    2008-01-01

    BACKGROUND: The deletion-allele of the angiotensin-converting enzyme (ACE) gene and elevated ACE activity are associated with increased risk of severe hypoglycemia in type 1 diabetes. We explored whether genetic and phenotypic variations in other components of the renin-angiotensin system are sim...

  17. 21 CFR 862.1085 - Angiotensin I and renin test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Angiotensin I and renin test system. 862.1085 Section 862.1085 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test...

  18. The Renin-Angiotensin system in Hypertension and Diabetes: from man to rodent and back

    NARCIS (Netherlands)

    L.C.W. Roksnoer (Lodi)

    2016-01-01

    markdownabstractAbstract In addition to the systemic (endocrine) RAS, it is generally believed that the kidney has its own (paracrine) RAS, since it is capable of local angiotensin II synthesis, and all RAS components are expressed locally. Another source of RAS components in the kidney may be

  19. Functional interactions between 7TM receptors in the renin-angiotensin system--dimerization or crosstalk?

    DEFF Research Database (Denmark)

    Lyngsø, Christina; Erikstrup, Niels; Hansen, Jakob L

    2008-01-01

    The Renin-Angiotensin System (RAS) is important for the regulation of cardiovascular physiology, where it controls blood pressure, and salt- and water homeostasis. Dysregulation of RAS can lead to severe diseases including hypertension, diabetic nephropathy, and cardiac arrhythmia, and -failure...

  20. Cardiac repolarization during hypoglycaemia in type 1 diabetes: impact of basal renin-angiotensin system activity

    DEFF Research Database (Denmark)

    Due-Andersen, Rikke; Høi-Hansen, Thomas; Larroude, Charlotte Ellen

    2008-01-01

    AIMS: Hypoglycaemia-induced cardiac arrhythmias may be involved in the pathogenesis of the 'dead-in-bed syndrome' in patients with type 1 diabetes. Evidence suggests that the renin-angiotensin system (RAS) influences the occurrence of arrhythmias. The aim of this study was to explore if basal RAS...

  1. Structural adaptation to ischemia in skeletal muscle: effects of blockers of the renin-angiotensin system

    NARCIS (Netherlands)

    Scheidegger, K. J.; Nelissen-Vrancken, M. H.; Leenders, P. J.; Daemen, M. J.; Smits, J. F.; Wood, J. M.

    1997-01-01

    To investigate the effects of long-term treatment with blockers of the renin-angiotensin system on capillarization and growth of fibers in ischemic hind-limb muscles and in muscles under normal growth conditions. Ischemia was induced by partial ligation of the left common iliac artery. Ischemia

  2. Angiotensin-II-derived reactive oxygen species on baroreflex sensitivity during hypertension: new perspectives

    Directory of Open Access Journals (Sweden)

    Thyago Moreira Queiroz

    2013-05-01

    Full Text Available Hypertension is a multifactorial disorder which has been associated with the reduction in baroreflex sensitivity and autonomic dysfunction. Several studies have revealed that increased reactive oxygen species (ROS generated by nicotinamide adenine dinucleotide phosphate [NAD(PH] oxidase, following activation of type 1 receptor (AT1R by Angiotensin-(Ang II, the main peptide of the Renin–Angiotensin–Aldosterone System (RAAS, is the central mechanism involved in Angiotensin-II-derived hypertension. In the present review we will discuss the role of Angiotensin-II and oxidative stress in hypertension, the relationship between the baroreflex sensitivity (BRS and the genesis of hypertension and how the oxidative stress triggers baroreflex dysfunction in several models of hypertension. Finally, we will describe some novel therapeutic drugs for improving the baroreflex sensitivity during hypertension.

  3. Screening for primary aldosteronism- normal ranges for aldosterone ...

    African Journals Online (AJOL)

    Objective. To establish normal ranges for plasma aldosterone, renin and aldosterone / renin (A/ R) ratio in South African normotensives under typical ou tpatient conditions, and to estimate the prevalence of primary aldosteronism (PA) among hypertensives in primary care settings. Design and methods. One hundred and ...

  4. Renin-angiotensin system: an old player with novel functions in skeletal muscle.

    Science.gov (United States)

    Cabello-Verrugio, Claudio; Morales, María Gabriela; Rivera, Juan Carlos; Cabrera, Daniel; Simon, Felipe

    2015-05-01

    Skeletal muscle is a tissue that shows the most plasticity in the body; it can change in response to physiological and pathological stimuli. Among the diseases that affect skeletal muscle are myopathy-associated fibrosis, insulin resistance, and muscle atrophy. A common factor in these pathologies is the participation of the renin-angiotensin system (RAS). This system can be functionally separated into the classical and nonclassical RAS axis. The main components of the classical RAS pathway are angiotensin-converting enzyme (ACE), angiotensin II (Ang-II), and Ang-II receptors (AT receptors), whereas the nonclassical axis is composed of ACE2, angiotensin 1-7 [Ang (1-7)], and the Mas receptor. Hyperactivity of the classical axis in skeletal muscle has been associated with insulin resistance, atrophy, and fibrosis. In contrast, current evidence supports the action of the nonclassical RAS as a counter-regulator axis of the classical RAS pathway in skeletal muscle. In this review, we describe the mechanisms involved in the pathological effects of the classical RAS, advances in the use of pharmacological molecules to inhibit this axis, and the beneficial effects of stimulation of the nonclassical RAS pathway on insulin resistance, atrophy, and fibrosis in skeletal muscle. © 2015 Wiley Periodicals, Inc.

  5. Contribution of the renin-angiotensin system in chronic foot-shock induced hypertension in rats.

    Science.gov (United States)

    Wang, Lin-Hui; Dong, Tao; Liu, Bei-Bei; Zhao, Xiao-Dong; Chen, Jing-Wei; Murao, Koji; Zhu, Wei; Zhang, Guo-Xing

    2015-01-15

    Chronic foot shock has been demonstrated to induce hypertension. The present study was designed to explore whether the renin-angiotensin system (RAS) plays a role in this process and the possible mechanisms involved in chronic-foot-shock-induced hypertension. Male Sprague-Dawley rats were subjected to a two-week foot shock with or without an angiotensin II (Ang II) type 1 receptor blocker (ARB, candesartan) or an angiotensin I converting enzyme inhibitor (ACEI, captopril). The expression of RAS components in the central nervous and circulatory systems was examined. Antioxidant levels in the plasma were monitored. Two-week foot shock significantly increased systolic blood pressure (SBP). Angiotensinogen, angiotensin I converting enzyme (ACE)-1, ACE-2, angiotensin type 1a and type 1b receptors, and vasopressin (VAP) mRNA expression in the cerebral cortex and hypothalamus were increased along with the concentration of renin and Ang II in the plasma; these changes were accompanied by decreased glutathione peroxidase activity and increased lipid peroxidation levels and plasma corticosterone concentrations. Both candesartan and captopril suppressed not only the increases in SBP but also the increases in VAP expression in the hypothalamus and RAS components in the central nervous system and the circulatory system. The decreases in antioxidant levels and the increases in lipid peroxidation and corticosterone levels were also partially reversed by candesartan or captopril treatment. Chronic foot shock increases expression of the main RAS components, which play an important role in the development of high blood pressure through increased VAP levels, oxidative stress levels and stress hormone levels. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Corticosteroids decrease glomerular angiotensin receptors

    Energy Technology Data Exchange (ETDEWEB)

    Douglas, J.G.

    1987-03-01

    Angiotensin II (ANG II) receptors of glomerular mesangial cells are regulated in vivo by changes in Na balance, effects that are presumed to be secondary to changes in circulating ANG II. However, since changes in ANG II were accompanied by parallel changes in plasma aldosterone in all models tested, it is possible that aldosterone may have also participated in the modulation of glomerular ANG II receptors. To test this hypothesis, short-term aldosterone infusions within the physiological range were employed to favor actions that would be mediated through a high-affinity mineralocorticoid receptor. The glucocorticoid, dexamethasone, was also tested to determine the mineralocorticoid specificity of the response. Two infusion rates were associated with a decrease in glomerular /sup 125/I ANG II receptor density of 33 and 45%, respectively. Serum potassium and urinary Na/K ratio were lower in the aldosterone group. Spironolactone abolished the effect of aldosterone consistent with an action mediated through a specific mineralocorticoid receptor. These studies support the hypothesis that corticosteroids modulate glomerular ANG II receptors and validate the complexity of glomerular receptor modulation. The downregulation observed would be expected to diminish the ability of ANG II to influence glomerular hemodynamics in models such as mineralocorticoid and glucocorticoid-induced hypertension.

  7. Primary aldosteronism. Clinical management

    International Nuclear Information System (INIS)

    Grant, C.S.; Carpenter, P.; van Heerden, J.A.; Hamberger, B.

    1984-01-01

    We retrospectively reviewed the clinical features, methods of diagnosis and localization, and results of treatment in 105 patients with primary aldosteronism seen between 1969 and 1981. Coincident with the use of computed tomography (CT), 131 I-6-beta-iodomethyl norcholesterol scans (NP-59), and postural response studies, the study group was temporally divided into pre-1976 and post-1976 groups, and subdivided into groups with aldosterone-producing adenoma (APA) and idiopathic hyperaldosteronism (IHA) due to bilateral adrenal hyperplasia. Our results indicate that aldosterone postural response studies and CT differentiate and localize APA and IHA reliably. Adrenalectomy is a safe and effective treatment for APA, whereas medical treatment alone is preferable for IHA

  8. Probiotics (VSL#3 prevent endothelial dysfunction in rats with portal hypertension: role of the angiotensin system.

    Directory of Open Access Journals (Sweden)

    Sherzad K Rashid

    Full Text Available AIMS: Portal hypertension characterized by generalized vasodilatation with endothelial dysfunction affecting nitric oxide (NO and endothelium-dependent hyperpolarization (EDH has been suggested to involve bacterial translocation and/or the angiotensin system. The possibility that ingestion of probiotics prevents endothelial dysfunction in rats following common bile duct ligation (CBDL was evaluated. METHODS: Rats received either control drinking water or the probiotic VSL#3 solution (50 billion bacteria.kg body wt⁻¹.day⁻¹ for 7 weeks. After 3 weeks, rats underwent surgery with either resection of the common bile duct or sham surgery. The reactivity of mesenteric artery rings was assessed in organ chambers, expression of proteins by immunofluorescence and Western blot analysis, oxidative stress using dihydroethidium, and plasma pro-inflammatory cytokine levels by flow cytometry. RESULTS: Both NO- and EDH-mediated relaxations to acetylcholine were reduced in the CBDL group compared to the sham group, and associated with a reduced expression of Cx37, Cx40, Cx43, IKCa and SKCa and an increased expression of endothelial NO synthase (eNOS. In aortic sections, increased expression of NADPH oxidase subunits, angiotensin converting enzyme, AT1 receptors and angiotensin II, and formation of ROS and peroxynitrite were observed. VSL#3 prevented the deleterious effect of CBDL on EDH-mediated relaxations, vascular expression of connexins, IKCa, SKCa and eNOS, oxidative stress, and the angiotensin system. VSL#3 prevented the CBDL-induced increased plasma TNF-α, IL-1α and MCP-1 levels. CONCLUSIONS: These findings indicate that VSL#3 ingestion prevents endothelial dysfunction in the mesenteric artery of CBDL rats, and this effect is associated with an improved vascular oxidative stress most likely by reducing bacterial translocation and the local angiotensin system.

  9. Renin–angiotensin system inhibition is not associated with increased sudden cardiac death, cardiovascular mortality or all-cause mortality in patients with aortic stenosis

    DEFF Research Database (Denmark)

    Bang, Casper N; Greve, Anders M; Køber, Lars

    2014-01-01

    BACKGROUND: Renin-angiotensin system inhibition (RASI) is frequently avoided in aortic stenosis (AS) patients because of fear of hypotension. We evaluated if RASI with angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) increased mortality in patients with mild...

  10. Aldosterone inhibits the fetal program and increases hypertrophy in the heart of hypertensive mice.

    Directory of Open Access Journals (Sweden)

    Feriel Azibani

    Full Text Available BACKGROUND: Arterial hypertension (AH induces cardiac hypertrophy and reactivation of "fetal" gene expression. In rodent heart, alpha-Myosin Heavy Chain (MyHC and its micro-RNA miR-208a regulate the expression of beta-MyHC and of its intronic miR-208b. However, the role of aldosterone in these processes remains unclear. METHODOLOGY/PRINCIPAL FINDINGS: RT-PCR and western-blot were used to investigate the genes modulated by arterial hypertension and cardiac hyperaldosteronism. We developed a model of double-transgenic mice (AS-Ren with cardiac hyperaldosteronism (AS mice and systemic hypertension (Ren. AS-Ren mice had increased (x2 angiotensin II in plasma and increased (x2 aldosterone in heart. Ren and AS-Ren mice had a robust and similar hypertension (+70% versus their controls. Anatomical data and echocardiography showed a worsening of cardiac hypertrophy (+41% in AS-Ren mice (P<0.05 vs Ren. The increase of ANP (x 2.5; P<0.01 mRNA observed in Ren mice was blunted in AS-Ren mice. This non-induction of antitrophic natriuretic peptides may be involved in the higher trophic cardiac response in AS-Ren mice, as indicated by the markedly reduced cardiac hypertrophy in ANP-infused AS-Ren mice for one month. Besides, the AH-induced increase of ßMyHC and its intronic miRNA-208b was prevented in AS-Ren. The inhibition of miR 208a (-75%, p<0.001 in AS-Ren mice compared to AS was associated with increased Sox 6 mRNA (x 1.34; p<0.05, an inhibitor of ßMyHC transcription. Eplerenone prevented all aldosterone-dependent effects. CONCLUSIONS/SIGNIFICANCE: Our results indicate that increased aldosterone in heart inhibits the induction of atrial natriuretic peptide expression, via the mineralocorticoid receptor. This worsens cardiac hypertrophy without changing blood pressure. Moreover, this work reveals an original aldosterone-dependent inhibition of miR-208a in hypertension, resulting in the inhibition of β-myosin heavy chain expression through the induction

  11. Cortisol-induced inhibition of ovine renin and aldosterone responses to hypotension

    International Nuclear Information System (INIS)

    Wood, C.E.; Silbiger, J.

    1987-01-01

    Previous studies from this laboratory have demonstrated that in preterm fetal sheep increases in plasma cortisol (F) concentration equal in amplitude to fetal F stress responses suppress plasma renin activity (PRA). The purpose of this study was to investigate the possibility that this negative interaction exists in adult sheep. Cortisol was measured by radioimmunoassay. Five conscious ewes with chronically prepared carotid arterial loops were infused intravenously with F or vehicle for 5 h. One hour after the end of F or vehicle infusion, renin secretion was stimulated by hypotension produced by infusion of sodium nitroprusside. F infusion increased plasma F; during vehicle infusion plasma F did not change. F infusion decreased hematocrit from 29 +/- 2 to 26 +/- 1%. Basal PRA in vehicle- and F-infused groups were 0.4 +/- 0 and 0.2 +/- 0.1 ng angiotensin I-ml -1 -h -1 and did not change. In vehicle-infused ewes, PRA increased from 0.4 +/- 0 to 4.6 +/- 0.4 and plasma aldosterone from 26.0 +/- 1.0 to 173.1 +/- 21.8 pg/ml, while in F-infused ewes, PRA increased from 0.2 +/- 1 to 3.3 +/- 0.4 ng angiotensin I-ml -1 -h -1 and aldosterone from 25.0 +/- 0 to 48.2 +/- 23.2 pg/ml, significantly smaller responses. These results suggest that repeated stress may modulate the responses of the renin-angiotensin system in this species

  12. Angiotensin inhibition in heart failure

    Directory of Open Access Journals (Sweden)

    John JV Mcmurray

    2004-03-01

    Full Text Available Survival in patients with heart failure remains very poor, and is worse than that for most common cancers, including bowel cancer in men and breast cancer in women. The renin-angiotensin-aldosterone system (RAAS is not completely blocked by angiotensin-converting enzyme (ACE inhibition. Blockade of the RAAS at the AT1-receptor has the theoretical benefit of more effective blockade of the actions of angiotensin II. ACE inhibitors (ACE-Is prevent the breakdown of bradykinin: this has been blamed for some of the unwanted effects of ACE-Is although bradykinin may have advantageous effects in heart failure. Consequently, ACE-Is and ARBs might be complementary or even additive treatments; recent trials have tested these hypotheses. The Candesartan in Heart failure Assessment of Reduction in Mortality and morbidity (CHARM programme compared the angiotensin receptor blocker (ARB candesartan (target dose 32 mg once daily to placebo in three distinct but complementary populations of patients with symptomatic heart failure. These were: patients with reduced left ventricular ejection fraction (LVEF who were ACE-I-intolerant (CHARM-Alternative; patients with reduced LVEF who were being treated with ACE-Is (CHARM-Added; and patients with preserved left ventricular systolic function (CHARM-Preserved. There were substantial and statistically significant reductions in the primary composite end point (risk of cardiovascular death or hospital admission for heart failure in CHARM-Alternative. This was also the case in CHARM-Added, supporting and extending the findings of Val-HeFT. In CHARM-Preserved, the effect of candesartan on the primary end point did not reach conventional statistical significance though hospital admission for heart failure was reduced significantly with candesartan. In the CHARM-Overall programme there was a statistically borderline reduction in all-cause mortality with a clear reduction in cardiovascular mortality. All-cause mortality was

  13. Angiotensin inhibition in heart failure

    Directory of Open Access Journals (Sweden)

    John JV McMurray

    2004-03-01

    Full Text Available Survival in patients with heart failure remains very poor, and is worse than that for most common cancers, including bowel cancer in men and breast cancer in women. The renin-angiotensin-aldosterone system (RAAS is not completely blocked by angiotensin-converting enzyme (ACE inhibition. Blockade of the RAAS at the AT1-receptor has the theoretical benefit of more effective blockade of the actions of angiotensin II. ACE inhibitors (ACE-Is prevent the breakdown of bradykinin: this has been blamed for some of the unwanted effects of ACE-Is although bradykinin may have advantageous effects in heart failure. Consequently, ACE-Is and ARBs might be complementary or even additive treatments; recent trials have tested these hypotheses.The Candesartan in Heart failure Assessment of Reduction in Mortality and morbidity (CHARM programme compared the angiotensin receptor blocker (ARB candesartan (target dose 32 mg once daily to placebo in three distinct but complementary populations of patients with symptomatic heart failure. These were: patients with reduced left ventricular ejection fraction (LVEF who were ACE-I-intolerant (CHARM-Alternative; patients with reduced LVEF who were being treated with ACE-Is (CHARM-Added; and patients with preserved left ventricular systolic function (CHARM-Preserved.There were substantial and statistically significant reductions in the primary composite end point (risk of cardiovascular death or hospital admission for heart failure in CHARM-Alternative. This was also the case in CHARM-Added, supporting and extending the findings of Val-HeFT. In CHARM-Preserved, the effect of candesartan on the primary end point did not reach conventional statistical significance though hospital admission for heart failure was reduced significantly with candesartan. In the CHARM-Overall programme there was a statistically borderline reduction in all-cause mortality with a clear reduction in cardiovascular mortality. All-cause mortality was

  14. Severe hypoglycaemia in type 1 diabetes: impact of the renin-angiotensin system and other risk factors

    DEFF Research Database (Denmark)

    Pedersen-Bjergaard, Ulrik

    2009-01-01

    this thesis was conducted to assess the significance of severe hypoglycaemia as a clinical problem in the type 1 diabetic population, to evaluate the impact of known risk factors on occurrence of severe hypoglycaemia, and to identify new markers that could contribute to improved prediction of, and inspire...... targets and thereby open for prevention of severe hypoglycaemia. Furthermore, subjects with elevated renin-angiotensin system activity and a high rate of severe hypoglycaemia might benefit from pharmacological blockade of the renin-angiotensin system by ACE inhibitors or angiotensin II receptor blockers...

  15. Rapid non-genomic effects of aldosterone on rodent vascular function

    DEFF Research Database (Denmark)

    Uhrenholt, T R; Schjerning, J; Rasmussen, L E

    2004-01-01

    The main role of aldosterone is to maintain body sodium homeostasis by promoting salt reabsorption in the collecting ducts of the kidney. In the cardiovascular system, aldosterone may be harmful in a number of disease states by inducing fibrosis and vascular dysfunction. The present review descri....... However, in situations with endothelial dysfunction, such as congestive heart failure and hypertension, the negative effects of aldosterone are unopposed and inhibition of aldosterone is warranted....

  16. Effects of angiotensin II blockade on intermediate cardiovascular endpoints in haemodialysis patients: a randomised double-blind placebo-controlled one-year intervention trial (SAFIR study)

    DEFF Research Database (Denmark)

    Peters, Christian Daugaard; Kjærgaard, Krista Dybtved; Jensen, Jens Dam

    such as central aortic BP, carotid-femoral pulse wave velocity, left ventricular mass index, N-terminal prohormone of brain natriuretic peptide, heart rate variability, and plasma catecholamines were not significantly affected by irbesartan treatment. Changes in systolic BP during the study period correlated......Agents blocking the renin-angiotensin-aldosterone system are frequently used in end-stage renal disease patients, but whether they exert beneficial cardiovascular (CV) effects is unclear. The long-term effects of the angiotensin II receptor blocker irbesartan was investigated in 82 haemodialysis...

  17. Regulation of Adrenal Aldosterone Production by Serine Protease Prostasin

    Directory of Open Access Journals (Sweden)

    Takehiro Ko

    2010-01-01

    Full Text Available A serine protease prostasin has been demonstrated to have a pivotal role in the activation of the epithelial sodium channel. Systemic administration of adenovirus carrying human prostasin gene in rats resulted in an increase in plasma prostasin and aldosterone levels. However, the mechanism by which the elevation of prostasin levels in the systemic circulation stimulated the plasma aldosterone levels remains unknown. Therefore, we examined if prostasin increases the aldosterone synthesis in a human adrenocortical cell line (H295R cells. Luciferase assay using CYP11B2 promoter revealed that prostasin significantly increased the transcriptional activity of CYP11B2. Prostasin significantly increased both CYP11B2 mRNA expression and aldosterone production in a dose-dependent manner. Surprisingly, treatment with camostat mesilate, a potent prostasin inhibitor, had no effect on the aldosterone synthesis by prostasin and also a protease-dead mutant of prostasin significantly stimulated the aldosterone production. A T-type/L-type calcium channel blocker and a protein kinase C (PKC inhibitor significantly reduced the aldosterone synthesis by prostasin. Our findings suggest a stimulatory effect of prostasin on the aldosterone synthesis by adrenal gland through the nonproteolytic action and indicate a new role of prostasin in the systemic circulation.

  18. Study of the components of renin-angiotensinaldosterone system and KalliKrein -Kinin system in normal pregnancy

    International Nuclear Information System (INIS)

    Abreu Fagundes, V.G. de.

    1984-01-01

    The alterations in the renin-angiotensin-aldosterone system and Kallikrein-Kinin system were studied. The possible interferences of these systems on the arterial pressure and on the evolution of normal pregnancy were presented in the following situations: when the pregnant change from dorsal decumbency to left lateral decumbency and to orthostatic position. (M.A.C.) [pt

  19. Hemodynamic, morphometric and autonomic patterns in hypertensive rats - renin-angiotensin system modulation

    Directory of Open Access Journals (Sweden)

    Fernanda S. Zamo

    2010-01-01

    Full Text Available BACKGROUND: Spontaneously hypertensive rats develop left ventricular hypertrophy, increased blood pressure and blood pressure variability, which are important determinants of heart damage, like the activation of renin-angiotensin system. AIMS: To investigate the effects of the time-course of hypertension over 1 hemodynamic and autonomic patterns (blood pressure; blood pressure variability; heart rate; 2 left ventricular hypertrophy; and 3 local and systemic Renin-angiotensin system of the spontaneously hypertensive rats. METHODS: Male spontaneously hypertensive rats were randomized into two groups: young (n=13 and adult (n=12. Hemodynamic signals (blood pressure, heart rate, blood pressure variability (BPV and spectral analysis of the autonomic components of blood pressure were analyzed. LEFT ventricular hypertrophy was measured by the ratio of LV mass to body weight (mg/g, by myocyte diameter (μm and by relative fibrosis area (RFA, %. ACE and ACE2 activities were measured by fluorometry (UF/min, and plasma renin activity (PRA was assessed by a radioimmunoassay (ng/mL/h. Cardiac gene expressions of Agt, Ace and Ace2 were quantified by RT-PCR (AU. RESULTS: The time-course of hypertension in spontaneously hypertensive rats increased BPV and reduced the alpha index in adult spontaneously hypertensive rats. Adult rats showed increases in left ventricular hypertrophy and in RFA. Compared to young spontaneously hypertensive rats, adult spontaneously hypertensive rats had lower cardiac ACE and ACE2 activities, and high levels of PRA. No change was observed in gene expression of Renin-angiotensin system components. CONCLUSIONS: The observed autonomic dysfunction and modulation of Renin-angiotensin system activity are contributing factors to end-organ damage in hypertension and could be interacting. Our findings suggest that the management of hypertensive disease must start before blood pressure reaches the highest stable levels and the consequent

  20. Hyperparathyroidism and the calcium paradox of aldosteronism.

    Science.gov (United States)

    Chhokar, Vikram S; Sun, Yao; Bhattacharya, Syamal K; Ahokas, Robert A; Myers, Linda K; Xing, Zhiqing; Smith, Richard A; Gerling, Ivan C; Weber, Karl T

    2005-02-22

    Aldosteronism may account for oxi/nitrosative stress, a proinflammatory phenotype, and wasting in congestive heart failure. We hypothesized that aldosterone/1% NaCl treatment (ALDOST) in rats enhances Ca2+ and Mg2+ excretion and leads to systemic effects, including bone loss. At 1, 2, 4, and 6 weeks of ALDOST, we monitored Ca2+ and Mg2+ excretion, ionized [Ca2+]o and [Mg2+]o, parathyroid hormone and 1-antiproteinase activity in plasma, bone mineral density, bone strength, Ca2+ and Mg2+ content in peripheral blood mononuclear cells (PBMCs) and ventricular tissue, and lymphocyte H2O2 production. A separate group received spironolactone (Spiro), an aldosterone receptor antagonist. Age- and gender-matched unoperated and untreated rats served as controls. ALDOST induced a marked (Phyperparathyroidism and bone resorption. Ca2+ overloading of PBMCs and cardiac tissue leads to oxi/nitrosative stress and a proinflammatory phenotype.

  1. Aldosterone dysregulation with aging predicts renal vascular function and cardiovascular risk.

    Science.gov (United States)

    Brown, Jenifer M; Underwood, Patricia C; Ferri, Claudio; Hopkins, Paul N; Williams, Gordon H; Adler, Gail K; Vaidya, Anand

    2014-06-01

    Aging and abnormal aldosterone regulation are both associated with vascular disease. We hypothesized that aldosterone dysregulation influences the age-related risk of renal vascular and cardiovascular disease. We conducted an analysis of 562 subjects who underwent detailed investigations under conditions of liberal and restricted dietary sodium intake (1124 visits) in the General Clinical Research Center. Aldosterone regulation was characterized by the ratio of maximal suppression to stimulation (supine serum aldosterone on a liberal sodium diet divided by the same measure on a restricted sodium diet). We previously demonstrated that higher levels of this Sodium-modulated Aldosterone Suppression-Stimulation Index (SASSI) indicate greater aldosterone dysregulation. Renal plasma flow (RPF) was determined via p-aminohippurate clearance to assess basal renal hemodynamics and the renal vascular responses to dietary sodium manipulation and angiotensin II infusion. Cardiovascular risk was calculated using the Framingham Risk Score. In univariate linear regression, older age (β=-4.60; Page and SASSI, where the inverse relationship between SASSI and RPF was most apparent with older age (Page may interact to mediate renal vascular disease. Our findings suggest that the combination of aldosterone dysregulation and renal vascular dysfunction could additively increase the risk of future cardiovascular outcomes; therefore, aldosterone dysregulation may represent a modifiable mechanism of age-related vascular disease.

  2. [The renin-angiotensin system and the sympathetic nervous system in essential hypertension].

    Science.gov (United States)

    Vincent, M; Milon, H; Revol, T; Annat, G; Froment, A; Sassard, J; Cier, J F

    1982-06-01

    In 112 patients with essential hypertension (HTA), free of any therapeutic and receiving the standard ward, a significant inverse relationship was found between age and plasma renin activity (PRA) and plasma aldosterone (PA), measured in the supine and upright position. Urinary epinephrine and norepinephrine were not related with age. When dividing the patients in 4 different age groups, it appeared that those younger than 30 years exhibited a significantly higher PRA and PA values and a higher frequency of borderline hypertension (45 p. 100) than the older ones (12 p. 100). So as to determine the characteristics associated with borderline HTA, it was necessary to eliminate the influence of age. This was achieved by comparing two groups of carefully age-matched patients, one with borderline HTA and the other with stable HTA. The only significant difference found was a significantly more marked increase in PRA in response to orthostatism, in patients with borderline HTA. Since renin responses to an orthostatic stress are largely mediated by renal nerves, this result suggest that borderline HTA could be associated with an increased reactivity of the sympathetic nervous system.

  3. Inflammatory Renin-Angiotensin System Disruption Attenuates Sensory Hyperinnervation and Mechanical Hypersensitivity in a Rat Model of Provoked Vestibulodynia.

    Science.gov (United States)

    Chakrabarty, Anuradha; Liao, Zhaohui; Mu, Ying; Smith, Peter G

    2018-03-01

    Vestibulodynia is characterized by perivaginal mechanical hypersensitivity, hyperinnervation, and abundant inflammatory cells expressing renin-angiotensin system proteins. We developed a tractable rat model of vestibulodynia to further assess the contributions of the renin-angiotensin system. Complete Freund's adjuvant injected into the posterior vestibule induced marked vestibular hypersensitivity throughout a 7-day test period. Numbers of axons immunoreactive for PGP9.5, calcitonin gene-related peptide, and GFRα2 were increased. Numbers of macrophages and T cells were also increased whereas B cells were not. Renin-angiotensin-associated proteins were abundant, with T cells as well as macrophages contributing to increased renin and angiotensinogen. Media conditioned with inflamed vestibular tissue promoted neurite sprouting by rat dorsal root ganglion neurons in vitro, and this was blocked by the angiotensin II receptor type 2 receptor antagonist PD123319 or by an angiotensin II function blocking antibody. Sensory axon sprouting induced by inflamed tissue was dependent on activity of angiotensin-converting enzyme or chymase, but not cathepsin G. Thus, vestibular Complete Freund's adjuvant injection substantially recapitulates changes seen in patients with provoked vestibulodynia, and shows that manipulation of the local inflammatory renin-angiotensin system may be a useful therapeutic strategy. This study provides evidence that inflammation of the rat vestibule induces a phenotype recapitulating behavioral and cytological features of human vestibulodynia. The model confirms a crucial role of the local inflammatory renin-angiotensin system in hypersensitivity and hyperinnervation. Targeting this system holds promise for developing new nonopioid analgesic treatment strategies. Copyright © 2017 The American Pain Society. Published by Elsevier Inc. All rights reserved.

  4. Associations of renin-angiotensin system genetic polymorphisms and clinical course after aneurysmal subarachnoid hemorrhage.

    Science.gov (United States)

    Griessenauer, Christoph J; Tubbs, R Shane; Foreman, Paul M; Chua, Michelle H; Vyas, Nilesh A; Lipsky, Robert H; Lin, Mingkuan; Iyer, Ramaswamy; Haridas, Rishikesh; Walters, Beverly C; Chaudry, Salman; Malieva, Aisana; Wilkins, Samantha; Harrigan, Mark R; Fisher, Winfield S; Shoja, Mohammadali M

    2017-05-01

    OBJECTIVE Renin-angiotensin system (RAS) genetic polymorphisms are thought to play a role in cerebral aneurysm formation and rupture. The Cerebral Aneurysm Renin Angiotensin System (CARAS) study prospectively evaluated associations of common RAS polymorphisms and clinical course after aneurysmal subarachnoid hemorrhage (aSAH). METHODS The CARAS study prospectively enrolled aSAH patients at 2 academic centers in the United States. A blood sample was obtained from all patients for genetic evaluation and measurement of plasma angiotensin converting enzyme (ACE) concentration. Common RAS polymorphisms were detected using 5'exonuclease genotyping assays and pyrosequencing. Analysis of associations of RAS polymorphisms and clinical course after aSAH were performed. RESULTS A total of 166 patients were screened, and 149 aSAH patients were included for analysis. A recessive effect of allele I (insertion) of the ACE I/D (insertion/deletion) polymorphism was identified for Hunt and Hess grade in all patients (OR 2.76, 95% CI 1.17-6.50; p = 0.0206) with subsequent poor functional outcome. There was a similar effect on delayed cerebral ischemia (DCI) in patients 55 years or younger (OR 3.63, 95% CI 1.04-12.7; p = 0.0439). In patients older than 55 years, there was a recessive effect of allele A of the angiotensin II receptor Type 2 (AT2) A/C single nucleotide polymorphism (SNP) on DCI (OR 4.70, 95% CI 1.43-15.4; p = 0.0111). CONCLUSIONS Both the ACE I/D polymorphism and the AT2 A/C single nucleotide polymorphism were associated with an age-dependent risk of delayed cerebral ischemia, whereas only the ACE I/D polymorphism was associated with poor clinical grade at presentation. Further studies are required to elucidate the relevant pathophysiology and its potential implication in the treatment of patients with aSAH.

  5. ANGIOTENSIN RECEPTOR BLOCKERS WITH PLEIOTROPIC PROPERTIES: A NEW STANDARD IN CARDIOVASCULAR RISK MANAGEMENT AND TREATMENT OF HYPERTENSION

    Directory of Open Access Journals (Sweden)

    V. I. Podzolkov

    2017-01-01

    Full Text Available An increase in the activity of the renin-angiotensin-aldosterone system is one of the most important mechanisms for the realization of the cardiovascular continuum. The role that angiotensin receptor blockers play in achieving target figures of blood pressure and reducing cardiovascular risk is discussed. The importance of pleiotropic properties of angiotensin receptor blockers (in particular, activation of peroxisome proliferator-activated receptors gamma – PPAR-γ in the management of patients with insulin resistance, obesity, dyslipidemia is also covered. The evidence base for the use of telmisartan as a drug with pleiotropic effect in patients with arterial hypertension and associated diseases (diabetes mellitus, obesity, renal dysfunction is discussed. 

  6. Central metabolism of angiotensins

    International Nuclear Information System (INIS)

    Camara, C.G.

    1984-01-01

    High performance liquid chromatography analyses of the radioactivity derived from 125 I-angiotensins and bound to cellular receptors in the brain and peripheral tissue reveal that, first, the specifically bound radioactivity is a heterogeneous mixture of several molecular species. Second, the observed patterns of 125 I-angiotensin degradation are largely the result of the activity of membrane-bound amino peptidases, which are enriched in the crude mitochrondrial tissue fraction; third, in general, peptidase inhibitors decrease the apparent binding of 125 I-angiotensins to brain tissue, and they decrease this binding more than they decrease the degradation of the radioligands; fourth, peptidase inhibitors specific for individual enzymes, but not broad-spectrum peptidase inhibitors, actually decrease the amount of 125 I-angiotensin II bound to brain tissue, suggesting that angiotensin receptors in the brain may be associated with membrane-bound peptidases; fifth, tyrosine and other aromatic and branched-chain aliphatic amino acids, end products of angiotensin degradation by membrane peptidases, are quickly removed from the extracellular compartment by the activity of a high-affinity transport system, identical with the leucine-preferring uptake system, which is enriched in the crude mitochondrial tissue fraction, containing the synaptosomes; and sixth, the distribution of this uptake system in rat and gerbil brain is nearly identical and corresponds with the central distribution of 125 I-angiotensin binding in the gerbil, but neither with the distribution of 125 I-angiotensin II binding in the rat brain

  7. Targeting the renin-angiotensin system as novel therapeutic strategy for pulmonary diseases.

    Science.gov (United States)

    Tan, Wan Shun Daniel; Liao, Wupeng; Zhou, Shuo; Mei, Dan; Wong, Wai-Shiu Fred

    2017-12-27

    The renin-angiotensin system (RAS) plays a major role in regulating electrolyte balance and blood pressure. RAS has also been implicated in the regulation of inflammation, proliferation and fibrosis in pulmonary diseases such as asthma, acute lung injury (ALI), chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF) and pulmonary arterial hypertension (PAH). Current therapeutics suffer from some drawbacks like steroid resistance, limited efficacies and side effects. Novel intervention is definitely needed to offer optimal therapeutic strategy and clinical outcome. This review compiles and analyses recent investigations targeting RAS for the treatment of inflammatory lung diseases. Inhibition of the upstream angiotensin (Ang) I/Ang II/angiotensin receptor type 1 (AT 1 R) pathway and activation of the downstream angiotensin-converting enzyme 2 (ACE2)/Ang (1-7)/Mas receptor pathway are two feasible strategies demonstrating efficacies in various pulmonary disease models. More recent studies favor the development of targeting the downstream ACE2/Ang (1-7)/Mas receptor pathway, in which diminazene aceturate, an ACE2 activator, GSK2586881, a recombinant ACE2, and AV0991, a Mas receptor agonist, showed much potential for further development. As the pathogenesis of pulmonary diseases is so complex that RAS modulation may be used alone or in combination with existing drugs like corticosteroids, pirfenidone/nintedanib or endothelin receptor antagonists for different pulmonary diseases. Personalized medicine through genetic screening and phenotyping for angiotensinogen or ACE would aid treatment especially for non-responsive patients. This review serves to provide an update on the latest development in the field of RAS targeting for pulmonary diseases, and offer some insights into future direction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Involvement of Renin-Angiotensin System in Retinopathy of Prematurity - A Possible Target for Therapeutic Intervention.

    Directory of Open Access Journals (Sweden)

    Madhu Nath

    Full Text Available Examining the Retinal Renin Angiotensin System (RRAS in the ROP neonates and analyzing the possibility of modulating the RRAS to prevent the progression in Oxygen Induced Retinopathy (OIR model.Vitreous of ROP patients (n = 44, median age 5.5 months was quantified for RRAS components, VEGF, HIF-1α and compared with age matched control. The involvement of RRAS in ROP was tested in the rat model of OIR and compared with normoxia. Expressions of RAS components, VEGF and HIF-1α in retina were analyzed using qPCR and retinal structure and function was also analyzed. Effect of Angiotensin Converting Enzyme Inhibitor (ACEI and Angiotensin Receptor Blocker (ARB was evaluated and compared with Bevacizumab which served as a positive control. Drug penetration into retina was confirmed by liquid chromatography coupled ESI-tandem mass spectroscopy (LC-MS/MS.Multifold increase in the expression of RAS components in human vitreous and rat retina showed their involvement in ROP. ERG & fundus studies in OIR revealed the altered function of retina and were successfully prevented by ARB (telmisartan, ACEI (lisinopril and bevacizumab. Retinal analysis revealed the presence of ACEI and ARB in their therapeutic levels.This study for the first time demonstrates the upregulated level of RAS components in human ROP vitreous and further that the pharmacological intervention in RRAS can functionally and structurally preserve retina against the progression of ROP in the OIR model.

  9. Sex differences in the aging pattern of renin-angiotensin system serum peptidases.

    Science.gov (United States)

    Fernández-Atucha, A; Izagirre, A; Fraile-Bermúdez, A B; Kortajarena, M; Larrinaga, G; Martinez-Lage, P; Echevarría, E; Gil, J

    2017-01-01

    Serum peptidases, such as angiotensin-converting enzyme (ACE), angiotensin-converting enzyme-2 (ACE2), neutral endopeptidase (NEP), aminopeptidase N (APN), and aminopeptidase A (APA), are important elements of the renin-angiotensin system (RAS). Dysregulation of these enzymes has been associated with hypertension and cardiovascular risk. In the present study, serum activities of RAS peptidases were analyzed to evaluate the existence of sexual differences, with a possible different pattern in pre- and post-andropausal/post-menopausal participants. One hundred and eighteen healthy men and women between 41 and 70 years of age (58 women and 60 men) were recruited to participate in the study. Serum RAS-regulating enzymes were measured by spectrofluorimetry. Enzymatic activity was recorded as units of enzyme per milliliter of serum (U/mL). Significantly lower serum APA activity was observed in men with respect to women; no sex differences were detected for ACE, ACE2, NEP, or APN. Significantly lower APA and ACE serum activity were observed in older men compared to older women. In contrast, younger (menopausia, on the critical serum enzymatic activities of the RAS, which could correlate with sexual differences in cardiovascular risk.

  10. Angiotensin II in Refractory Septic Shock.

    Science.gov (United States)

    Antonucci, Elio; Gleeson, Patrick J; Annoni, Filippo; Agosta, Sara; Orlando, Sergio; Taccone, Fabio Silvio; Velissaris, Dimitrios; Scolletta, Sabino

    2017-05-01

    Refractory septic shock is defined as persistently low mean arterial blood pressure despite volume resuscitation and titrated vasopressors/inotropes in patients with a proven or suspected infection and concomitant organ dysfunction. Its management typically requires high doses of catecholamines, which can induce significant adverse effects such as ischemia and arrhythmias. Angiotensin II (Ang II), a key product of the renin-angiotensin-aldosterone system, is a vasopressor agent that could be used in conjunction with other vasopressors to stabilize critically ill patients during refractory septic shock, and reduce catecholamine requirements. However, very few clinical data are available to support Ang II administration in this setting. Here, we review the current literature on this topic to better understand the role of Ang II administration during refractory septic shock, differentiating experimental from clinical studies. We also consider the potential role of exogenous Ang II administration in specific organ dysfunction and possible pitfalls with Ang II in sepsis. Various issues remain unresolved and future studies should investigate important topics such as: the optimal dose and timing of Ang II administration, a comparison between Ang II and the other vasopressors (epinephrine; vasopressin), and Ang II effects on microcirculation.

  11. Leptin-Aldosterone-Neprilysin Axis: Identification of Its Distinctive Role in the Pathogenesis of the Three Phenotypes of Heart Failure in People With Obesity.

    Science.gov (United States)

    Packer, Milton

    2018-04-10

    Obesity (especially visceral adiposity) can be associated with 3 different phenotypes of heart failure: heart failure with a reduced ejection fraction, heart failure with a preserved ejection fraction, and high-output heart failure. All 3 phenotypes are characterized by an excessive secretion of aldosterone and sodium retention. In addition, obesity is accompanied by increased signaling through the leptin receptor, which can promote activation of both the sympathetic nervous system and the renin-angiotensin system and can directly stimulate the secretion of aldosterone. The deleterious interaction of leptin and aldosterone is potentiated by the simultaneous action of adiposity and the renal sympathetic nerves to cause overactivity of neprilysin; the loss of the counterbalancing effects of natriuretic peptides is exacerbated by an additional effect of both obesity and heart failure to interfere with adiponectin signaling. This intricate neurohormonal interplay leads to plasma volume expansion as well as to adverse ventricular remodeling and cardiac fibrosis. Furthermore, the activity of aldosterone and neprilysin is not only enhanced by obesity, but these mechanisms can also promote adipogenesis and adipocyte dysfunction, thereby enhancing the positive feedback loop. Last, in elderly obese women, changes in quantity and biology of epicardial adipose tissue further enhances the release of leptin and other proinflammatory adipokines, thereby leading to cardiac and systemic inflammation, end-organ fibrosis, and multiple comorbidities. Regardless of the phenotypic expression, activation of the leptin-aldosterone-neprilysin axis appears to contribute importantly to the evolution and progression of heart failure in people with obesity. Efforts to interfere with the detrimental interactions of this distinctive neurohormonal ecosystem with existing or novel therapeutic agents are likely to yield unique clinical benefits. © 2018 American Heart Association, Inc.

  12. Modulation of the renin-angiotensin system by food protein ...

    African Journals Online (AJOL)

    Chibuike

    derived BAPs can promote their use as safe antihypertensive agents. Moreover, future studies are needed to elucidate the long-term systemic molecular interactions of antihypertensive BAPs with the human genome, proteome and other cellular ...

  13. Differential clinical profile of candesartan compared to other angiotensin receptor blockers

    Directory of Open Access Journals (Sweden)

    Zimlichman R

    2011-12-01

    Full Text Available Relu Cernes1,2, Margarita Mashavi1,3, Reuven Zimlichman1,31The Brunner Institute for Cardiovascular Research, Wolfson Medical Center and Tel Aviv University, Tel Aviv, Israel; 2Department of Nephrology, Wolfson Medical Center, Holon, Israel; 3Department of Medicine, Wolfson Medical Center, Holon, IsraelAbstract: The advantages of blood pressure (BP control on the risks of heart failure and stroke are well established. The renin-angiotensin system plays an important role in volume homeostasis and BP regulation and is a target for several groups of antihypertensive drugs. Angiotensin II receptor blockers represent a major class of antihypertensive compounds. Candesartan cilexetil is an angiotensin II type 1 (AT[1] receptor antagonist (angiotensin receptor blocker [ARB] that inhibits the actions of angiotensin II on the renin-angiotensin-aldosterone system. Oral candesartan 8–32 mg once daily is recommended for the treatment of adult patients with hypertension. Clinical trials have demonstrated that candesartan cilexetil is an effective agent in reducing the risk of cardiovascular mortality, stroke, heart failure, arterial stiffness, renal failure, retinopathy, and migraine in different populations of adult patients including patients with coexisting type 2 diabetes, metabolic syndrome, or kidney impairment. Clinical evidence confirmed that candesartan cilexetil provides better antihypertensive efficacy than losartan and is at least as effective as telmisartan and valsartan. Candesartan cilexetil, one of the current market leaders in BP treatment, is a highly selective compound with high potency, a long duration of action, and a tolerability profile similar to placebo. The most important and recent data from clinical trials regarding candesartan cilexetil will be reviewed in this article.Keywords: angiotensin receptor blockers, candesartan, candesartan cilexetil, clinical trials, efficacy studies, safety, blood pressure

  14. Angiotensin Converting Enzyme Inhibitor Has a Protective Effect on Decompression Sickness in Rats

    Directory of Open Access Journals (Sweden)

    Aleksandra Mazur

    2018-03-01

    Full Text Available Introduction: Commercial divers, high altitude pilots, and astronauts are exposed to some inherent risk of decompression sickness (DCS, though the mechanisms that trigger are still unclear. It has been previously showed that diving may induce increased levels of serum angiotensin converting enzyme. The renin angiotensin aldosterone system (RAAS is one of the most important regulators of blood pressure and fluid volume. The purpose of the present study was to control the influence of angiotensin II on the appearance of DCS.Methods: Sprague Dawley rats have been pre-treated with inhibitor of angiotensin II receptor type 1 (losartan; 10 mg/kg, angiotensin-converting enzyme (ACE inhibitor (enalapril; 10 mg/kg, and calcium-entry blocker (nifedipine; 20 mg/kg. The experimental groups were treated for 4 weeks before exposure to hyperbaric pressure while controls were not treated. Seventy-five rats were subjected to a simulated dive at 1000 kPa absolute pressure for 45 min before starting decompression. Clinical assessment took place over a period of 60 min after surfacing. Blood samples were collected for measurements of TBARS, interleukin 6 (IL-6, angiotensin II (ANG II and ACE.Results: The diving protocol induced 60% DCS in non-treated animals. This ratio was significantly decreased after treatment with enalapril, but not other vasoactive drugs. Enalapril did not change ANG II or ACE concentration, while losartant decreased post dive level of ACE but not ANG II. None of the treatment modified the effect of diving on TBARS and IL-6 values.Conclusion: Results suggests that the rennin angiotensin system is involved in a process of triggering DCS but this has to be further investigated. However, a vasorelaxation mediated process, which potentially could increase the load of inert gas during hyperbaric exposure, and antioxidant properties were excluded by our results.

  15. Increased expression of the renin-angiotensin system and mast cell density but not of angiotensin-converting enzyme II in late stages of human heart failure.

    Science.gov (United States)

    Batlle, Montserrat; Roig, Eulàlia; Perez-Villa, Fèlix; Lario, Sergio; Cejudo-Martin, Pilar; García-Pras, Ester; Ortiz, José; Roqué, Mercé; Orús, Josefina; Rigol, Montserrat; Heras, Magdalena; Ramírez, José; Jimenez, Wladimiro

    2006-09-01

    The activation of the renin-angiotensin system (RAS) contributes to the progression of left ventricular dysfunction. A novel human homologue of the angiotensin-converting enzyme (ACE), named ACE2, has been described but its role in human heart failure (HF) has not been elucidated. Besides, there is controversy as to whether the major angiotensin II-forming-activity in heart is ACE or chymase released from mast cells. Furthermore, long-term blockade of nitric oxide (NO) synthesis has been shown to increase ACE activity. To assess the locally activated vasoactive mediators that may contribute to the ventricular deterioration process, we sought to simultaneously analyze their expression in failing hearts. We analyzed left ventricular biopsies from 30 patients with heart failure undergoing heart transplantation and 12 organ donors. The mRNA levels of ACE, ACE2, chymase and endothelial nitric oxide synthase (eNOS), were quantified by real-time polymerase chain reaction and mast cell density was assessed by immunohistochemistry. The mRNA levels of the atrial natriuretic peptide (ANP) and the brain natriuretic peptide (BNP) were also quantified as controls. There was higher ACE and chymase mRNA expression and mast cell density in failing than in control myocardium and no changes in ACE2 expression were detected. eNOS mRNA levels were lower in failing hearts. Both ANP and BNP expression were higher in pathological than in control samples. These data document a decompensation of vasoactive systems that may contribute to the progressive impairment of the myocardial function in HF. On the other hand, ACE2 mRNA expression is not altered in human end-stage HF.

  16. Cardiac repolarization during hypoglycaemia and hypoxaemia in healthy males: impact of renin-angiotensin system activity

    DEFF Research Database (Denmark)

    Due-Andersen, Rikke; Høi-Hansen, Thomas; Olsen, Niels Vidiendal

    2008-01-01

    AIMS: Activity in the renin-angiotensin system (RAS) may influence the susceptibility to cardiac arrhythmia. To study the effect of basal RAS activity on cardiac repolarization during myocardial stress induced by hypoglycaemia or hypoxaemia in healthy humans. METHODS AND RESULTS: Ten subjects...... with high RAS activity and 10 subjects with low RAS activity were studied on three different occasions: (i) hypoglycaemia (nadir P-glucose 2.7 +/- 0.5 mmol/L), (ii) hypoxaemia (nadir pO(2) 5.8 +/- 0.5 kPa), and (iii) normoglycaemic normoxia (control day). QT parameters were registered by Holter monitoring...

  17. The renin-angiotensin system; development and differentiation of the renal medulla

    DEFF Research Database (Denmark)

    Madsen, Kirsten; Robdrup Tinning, Anne; Marcussen, Niels

    2013-01-01

    Adverse events during fetal development can predispose the individual for cardiovascular disease later in life, a correlation known as fetal programming of adult hypertension. The "programming" events are not known but might reside in the kidneys due to these organs significant role...... on mechanisms of postnatal development the renal medulla and putting medullary developmental lesions into perspective with regard to the programming effect. Moreover, the renin-angiotensin system is critically involved in mammalian kidney development and signaling disorders give rise to developmental renal...

  18. Reduced plasma aldosterone concentrations in randomly selected patients with insulin-dependent diabetes mellitus.

    LENUS (Irish Health Repository)

    Cronin, C C

    2012-02-03

    Abnormalities of the renin-angiotensin system have been reported in patients with diabetes mellitus and with diabetic complications. In this study, plasma concentrations of prorenin, renin, and aldosterone were measured in a stratified random sample of 110 insulin-dependent (Type 1) diabetic patients attending our outpatient clinic. Fifty-four age- and sex-matched control subjects were also examined. Plasma prorenin concentration was higher in patients without complications than in control subjects when upright (geometric mean (95% confidence intervals (CI): 75.9 (55.0-105.6) vs 45.1 (31.6-64.3) mU I-1, p < 0.05). There was no difference in plasma prorenin concentration between patients without and with microalbuminuria and between patients without and with background retinopathy. Plasma renin concentration, both when supine and upright, was similar in control subjects, in patients without complications, and in patients with varying degrees of diabetic microangiopathy. Plasma aldosterone was suppressed in patients without complications in comparison to control subjects (74 (58-95) vs 167 (140-199) ng I-1, p < 0.001) and was also suppressed in patients with microvascular disease. Plasma potassium was significantly higher in patients than in control subjects (mean +\\/- standard deviation: 4.10 +\\/- 0.36 vs 3.89 +\\/- 0.26 mmol I-1; p < 0.001) and plasma sodium was significantly lower (138 +\\/- 4 vs 140 +\\/- 2 mmol I-1; p < 0.001). We conclude that plasma prorenin is not a useful early marker for diabetic microvascular disease. Despite apparently normal plasma renin concentrations, plasma aldosterone is suppressed in insulin-dependent diabetic patients.

  19. Immunohistochemical expression of intrarenal renin angiotensin system components in response to tempol in rats fed a high salt diet.

    Science.gov (United States)

    Cao, Gabriel; Della Penna, Silvana Lorena; Kouyoumdzian, Nicolás Martín; Choi, Marcelo Roberto; Gorzalczany, Susana; Fernández, Belisario Enrique; Toblli, Jorge Eduardo; Rosón, María Inés

    2017-01-06

    To determine the effect of tempol in normal rats fed high salt on arterial pressure and the balance between antagonist components of the renal renin-angiotensin system. Sprague-Dawley rats were fed with 8% NaCl high-salt (HS) or 0.4% NaCl (normal-salt, NS) diet for 3 wk, with or without tempol (T) (1 mmol/L, administered in drinking water). Mean arterial pressure (MAP), glomerular filtration rate (GFR), and urinary sodium excretion (UVNa) were measured. We evaluated angiotensin II (Ang II), angiotensin 1-7 (Ang 1-7), angiotensin converting enzyme 2 (ACE2), mas receptor (MasR), angiotensin type 1 receptor (AT1R) and angiotensin type 2 receptor (AT2R) in renal tissues by immunohistochemistry. The intake of high sodium produced a slight but significant increase in MAP and differentially regulated components of the renal renin-angiotensin system (RAS). This included an increase in Ang II and AT1R, and decrease in ACE-2 staining intensity using immunohistochemistry. Antioxidant supplementation with tempol increased natriuresis and GFR, prevented changes in blood pressure and reversed the imbalance of renal RAS components. This includes a decrease in Ang II and AT1R, as increase in AT2, ACE2, Ang (1-7) and MasR staining intensity using immunohistochemistry. In addition, the natriuretic effects of tempol were observed in NS-T group, which showed an increased staining intensity of AT2, ACE2, Ang (1-7) and MasR. These findings suggest that a high salt diet leads to changes in the homeostasis and balance between opposing components of the renal RAS in hypertension to favour an increase in Ang II. Chronic antioxidant supplementation can modulate the balance between the natriuretic and antinatriuretic components of the renal RAS.

  20. Clinical Evidence for the Cardiovascular Benefits of Angiotensin Receptor Blockers

    Directory of Open Access Journals (Sweden)

    Georg Nickenig

    2006-03-01

    Full Text Available Targeting the renin-angiotensin-aldosterone system (RAAS, specifically the effector peptide angiotensin II (Ang II, represents a major opportunity for slowing the progression of cardiovascular disease (CVD and, in turn, reducing the risk of morbidity and mortality. Inhibition of angiotensin-converting enzyme (ACE and selective blockade of Ang II AT1 receptors are two approaches through which the pathophysiological effects of Ang II can be targeted. Numerous clinical studies have established the benefits of ACE inhibitors P, (ACE-Is in lessening the morbidity and mortality burden of CVD. There are, however, tolerability concerns associated with ACE-Is, such as angioedema and dry cough. By blocking Ang II at the AT1 receptor level, Ang II receptor blockers (ARBs provide a more specific and complete blockade of the deleterious effects of Ang II and tend to have more favourable tolerability. A number of clinical trials have shown that ARBs are not only associated with positive outcomes across the CVD continuum but may also have a role in the prevention or delay of diabetes (a major cardiovascular risk factor. Ongoing trials are aiming to define the place of such agents in lessening morbidity and mortality from CVD.

  1. Brain renin-angiotensin system: fetal epigenetic programming by maternal protein restriction during pregnancy.

    Science.gov (United States)

    Goyal, Ravi; Goyal, Dipali; Leitzke, Arthur; Gheorghe, Ciprian P; Longo, Lawrence D

    2010-03-01

    Maternal protein malnutrition during pregnancy can lead to significant alterations in the systemic renin-angiotensin system (RAS) in the fetus. All components of the RAS are present in brain and may be altered in many disease states. Importantly, these disorders are reported to be of higher incidence in prenatally malnourished individuals. In the current study, we tested the hypothesis that antenatal maternal low protein diet (MLPD) leads to epigenetic changes and alterations in gene expression of brain RAS of the mouse fetus. Mice dams were given control and 50% MLPD during second half of the gestation. We analyzed messenger RNA (mRNA), microRNA (miRNA), promoter DNA methylation, and protein expression of various RAS genes in the fetal offspring. As a consequence of 50% MLPD, fetal brains showed increased mRNA expression of angiotensinogen and angiotensin converting enzyme-1 (ACE-1), with a decrease in mRNA levels of angiotensin II type-2 (AT2) receptors. In contrast, while angiotensinogen protein expression was unaltered, the protein levels of ACE-1 and AT2 receptor genes were significantly reduced in the fetal brain from the MLPD dams. Our results also demonstrated hypomethylation of the CpG islands in the promoter regions of ACE-1 gene, and upregulation of the miRNAs, mmu-mir-27a and 27b, which regulate ACE-1 mRNA translation. Furthermore, our study showed reduced expression of the miRNA mmu-mir-330, which putatively regulates AT2 translation. For the developing fetal brain RAS, MLPD leads to significant alterations in the mRNA and protein expression, with changes in DNA methylation and miRNA, key regulators of hypertension in adults.

  2. The association of renin–angiotensin system blockades and pneumonia requiring admission in patients with COPD

    Directory of Open Access Journals (Sweden)

    Kim J

    2016-09-01

    Full Text Available Junghyun Kim,1 Jung-Kyu Lee,2 Eun Young Heo,2 Hee Soon Chung,2 Deog Kyeom Kim2 1Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, Seoul National University Hospital, 2Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul, Korea Background: The hallmark of COPD is chronic airway inflammation, which may be mediated by renin–angiotensin system. The renin–angiotensin system blockers such as angiotensin-converting enzyme inhibitors (ACEi and angiotensin II receptor blockers (ARBs have exhibited anti-inflammatory and immunomodulatory effects in patients with various diseases. We explored the effects of ACEi and ARBs on the risk of pneumonia in patients with COPD.Methods: A nested case–control study was performed on COPD patients recruited from January 2010 to August 2013 in two referral hospitals in Korea. A total of 130 COPD patients admitted with pneumonia were included, and 245 COPD patients without pneumonia were selected as controls from a total of 1,646 such patients. Controls were matched with test patients by age, sex, and severity of airflow limitation. The effects of ACEi/ARBs use on the odds ratio (OR for the development of pneumonia were tested through conditional logistic regression.Results: Elderly patients (over 70 years of age constituted ~30% of each group; most of the patients were male (85%. Of the COPD patients with pneumonia, 21.5% had taken ACEi/ARBs for a mean of 9.8 months (standard deviation ±3.5 months. The proportions of ACEi/ARBs users and the mean duration of such use did not differ when compared to those of the control patients (26.9%, P=0.25; 9.6±3.6 months, P=0.83. Univariate analyses indicated that the use of ACEi/ARBs was not associated with a decreased risk of pneumonia (OR =0.70, 95% confidence interval 0.41–1.23, P=0.21, whereas both a history of pulmonary

  3. Dietary sodium deprivation evokes activation of brain regional neurons and down-regulation of angiotensin II type 1 receptor and angiotensin-convertion enzyme mRNA expression.

    Science.gov (United States)

    Lu, B; Yang, X J; Chen, K; Yang, D J; Yan, J Q

    2009-12-15

    Previous studies have indicated that the renin-angiotensin-aldosterone system (RAAS) is implicated in the induction of sodium appetite in rats and that different dietary sodium intakes influence the mRNA expression of central and peripheral RAAS components. To determine whether dietary sodium deprivation activates regional brain neurons related to sodium appetite, and changes their gene expression of RAAS components of rats, the present study examined the c-Fos expression after chronic exposure to low sodium diet, and determined the relationship between plasma and brain angiotensin I (ANG I), angiotensin II (ANG II) and aldosterone (ALD) levels and the sodium ingestive behavior variations, as well as the effects of prolonged dietary sodium deprivation on ANG II type 1 (AT1) and ANG II type 2 (AT2) receptors and angiotensin-convertion enzyme (ACE) mRNA levels in the involved brain regions using the method of real-time polymerase chain reaction (PCR). Results showed that the Fos immunoreactivity (Fos-ir) expression in forebrain areas such as subfornical organ (SFO), paraventricular hypothalamic nuclei (PVN), supraoptic nucleus (SON) and organum vasculosum laminae terminalis (OVLT) all increased significantly and that the levels of ANG I, ANG II and ALD also increased in plasma and forebrain in rats fed with low sodium diet. In contrast, AT1, ACE mRNA in PVN, SON and OVLT decreased significantly in dietary sodium depleted rats, while AT2 mRNA expression did not change in the examined areas. These results suggest that many brain areas are activated by increased levels of plasma and/or brain ANG II and ALD, which underlies the elevated preference for hypertonic salt solution after prolonged exposure to low sodium diet, and that the regional AT1 and ACE mRNA are down-regulated after dietary sodium deprivation, which may be mediated by increased ANG II in plasma and/or brain tissue.

  4. Dual renin-angiotensin system blockade at optimal doses for proteinuria.

    Science.gov (United States)

    Laverman, Gozewijn D; Navis, Gerjan; Henning, Robert H; de Jong, Paul E; de Zeeuw, Dick

    2002-09-01

    The antiproteinuric effect of combining the angiotensin-converting enzyme (ACE) inhibitor lisinopril and the angiotensin II (Ang II) antagonist losartan was compared to that of the optimal antiproteinuric doses of monotherapy. To this purpose, lisinopril and losartan were studied in 9 nondiabetic renal patients with median proteinuria 4.5 g/day (95% CI, 3.5, 6.4), creatinine clearance of 80 mL/min (95% CI, 66, 96), and mean arterial pressure (MAP) of 102 mm Hg (95% CI, 93, 112). First, in two protocols with six-week treatment periods per dose, the optimal antiproteinuric dose of each drug was established in each patient. Losartan and lisinopril were used in randomized order, each preceded by a baseline period without medication. The doses of losartan (mg/day) were 50, 100, 150, and again 50. The lisinopril doses were 10, 20, 40, and again 10. After the second protocol, patients were treated with a combination, using the optimal antiproteinuric doses established for the individual drugs. The antiproteinuric response by losartan was optimal at 100 mg (-46%; 95% CI, -60, -24%), being larger than at the 50 mg dose (-27%; 95% CI, -42, -4%, P 150 mg dose (-46%; 95% CI, -58; -20%). Proteinuria decreased further at each up-titration step of lisinopril to -75% (95% CI, -85, -43%) at the 40 mg dose. Combination therapy reduced proteinuria more effectively (-85%; 95% CI, -96, -58) than monotherapy with losartan, and to a lesser extent than with lisinopril. Optimal blood pressure responses were obtained at similar doses. Dose-titration with a renin-angiotensin system blocker, followed by add-on therapy is highly effective in order to reduce proteinuria. The safety of this regimen needs to be addressed in future studies.

  5. Renin-angiotensin system blockade therapy after transcatheter aortic valve implantation.

    Science.gov (United States)

    Ochiai, Tomoki; Saito, Shigeru; Yamanaka, Futoshi; Shishido, Koki; Tanaka, Yutaka; Yamabe, Tsuyoshi; Shirai, Shinichi; Tada, Norio; Araki, Motoharu; Naganuma, Toru; Watanabe, Yusuke; Yamamoto, Masanori; Hayashida, Kentaro

    2018-04-01

    The persistence of left ventricular (LV) hypertrophy is associated with poor clinical outcomes after transcatheter aortic valve implantation (TAVI) for aortic stenosis. However, the optimal medical therapy after TAVI remains unknown. We investigated the effect of renin-angiotensin system (RAS) blockade therapy on LV hypertrophy and mortality in patients undergoing TAVI. Between October 2013 and April 2016, 1215 patients undergoing TAVI were prospectively enrolled in the Optimized CathEter vAlvular iNtervention (OCEAN)-TAVI registry. This cohort was stratified according to the postoperative usage of RAS blockade therapy with angiotensin-converting enzyme (ACE) inhibitors or angiotensin-receptor blockers (ARBs). Patients with at least two prescriptions dispensed 180 days apart after TAVI and at least a 6-month follow-up constituted the RAS blockade group (n=371), while those not prescribed any ACE inhibitors or ARBs after TAVI were included in the no RAS blockade group (n=189). At 6 months postoperatively, the RAS blockade group had significantly greater LV mass index regression than the no RAS blockade group (-9±24% vs -2±25%, p=0.024). Kaplan-Meier analysis revealed a significantly lower cumulative 2-year mortality in the RAS blockade than that in the no RAS blockade group (7.5% vs 12.5%; log-rank test, p=0.031). After adjusting for confounding factors, RAS blockade therapy was associated with significantly lower all-cause mortality (HR, 0.45; 95% CI 0.22 to 0.91; p=0.025). Postoperative RAS blockade therapy is associated with greater LV mass index regression and reduced all-cause mortality. These data need to be confirmed by a prospective randomised controlled outcome trial. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  6. Chronic Renin-Angiotensin System (RAS) Blockade May Not Induce Hypotension During Anaesthesia for Bariatric Surgery.

    Science.gov (United States)

    Salvetti, Guido; Di Salvo, Claudio; Ceccarini, Giovanni; Abramo, Antonio; Fierabracci, Paola; Magno, Silvia; Piaggi, Paolo; Vitti, Paolo; Santini, Ferruccio

    2016-06-01

    The use of angiotensin-converting enzyme inhibitors (ACE-I) and angiotensin II receptor blockers (ARB) for the treatment of hypertensive obese patients is steadily increasing. Some studies have reported that the use of these drugs was associated with an increased risk of hypotensive episodes, during general anaesthesia. The number of bariatric procedures is also increasing worldwide, but there is a lack of studies investigating the hypotensive effect of renin-angiotensin system (RAS) blockers in severely obese patients during general anaesthesia for bariatric surgery. The aim of this pilot study was to evaluate hemodynamic changes induced by general anaesthesia in obese patients chronically treated with ACE-I or ARB compared to a control group not treated with antihypertensive therapy. Fourteen obese subjects (mean body mass index (BMI) 47.5 kg/m(2)) treated with ACE-I or ARB and twelve obese (mean BMI 45.7 kg/m2) controls not treated with antihypertensive therapy underwent general anaesthesia to perform laparoscopic bariatric surgery. Systolic blood pressure, diastolic blood pressure, and heart rate were monitored continuously and registered at different time points: T0 before induction, then at 2, 5, 7, 10, 15, 20, 30, 60, 90, 120, and 150 min after induction, and the last time point taken following recovery from anaesthesia. A progressive reduction of both systolic and diastolic blood pressure values was observed without significant differences between the two groups. A similar trend of heart rate values was observed. In conclusion, our pilot study suggests that RAS blockers may be continued during the perioperative period in patients undergoing bariatric surgery, without increasing the risk of hypotensive episodes.

  7. Renin-angiotensin system at the crossroad of hypertension and hypercholesterolemia.

    Science.gov (United States)

    Borghi, C; Urso, R; Cicero, A F

    2017-02-01

    The aim of this study is to discuss the reliable scientific evidence of an interactive link between hypertension and hypercholesterolemia considering the metabolic pathways and the pathogenetic mechanisms connecting the two risk factors. Hypertension and hypercholesterolemia are highly prevalent in the general population and their coexistence in the same subjects additively increases the risk of cardiovascular disease. Probably, hypercholesterolemia is also a risk factor for the development of hypertension. On the other side, it is also possible that lipid-lowering treatment could improve blood pressure control. Although the mechanisms of interaction between these two risk factors have not been completely elucidated thus far, there is rapidly growing evidence that the involvement of the renin-angiotensin system (RAS) can be considered as the common link between hypertension and hypercholesterolemia. In particular, hypercholesterolemia seems to promote the upregulation of type 1 angiotensin II (AT1) receptor genes because of an increase in the stability of mRNA followed by structural overexpression of vascular AT1 receptors for angiotensin II. The treatment of both risk factors greatly improves individual risk profile, especially when statins and RAS blockers are used together. Hypertension and hypercholesterolemia are highly coprevalent and strongly related from a pathophysiological point of view. The RAS could be the main mediator of this link. Copyright © 2016 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

  8. The placental renin-angiotensin system and oxidative stress in pre-eclampsia.

    Science.gov (United States)

    Mistry, H D; Kurlak, L O; Broughton Pipkin, F

    2013-02-01

    There is an inverse correlation between human birthweight and umbilical venous angiotensin II (AngII) concentrations. Oxidative stress and increased pro-renin receptor (PRR) both enhance the cleavage of angiotensin I from angiotensinogen (AGT). Pre-eclampsia, a hypertensive disorder of pregnancy, manifests as high blood pressure and proteinuria, and is a state of increased oxidative stress. Pre-eclampsia will be associated with increased placental expression of components of the renin-angiotensin system, which could result in reduced infant birthweight. Biopsies were taken 1 cm from the placental edge from 27 normotensive controls and 23 pre-eclamptic White European women. Immunohistochemistry was performed for AGT, PRR, glutathione peroxidase 3 (GPx3) and the AT1R and AT2R AngII receptors. Protein expression was semi-quantitatively assessed (H-score). AT1R expression was significantly increased in pre-eclamptic placentae, and negatively correlated with birthweight (r = -0.529, P = 0.009). AT1R expression was also negatively correlated with GPx3 expression overall (r = -0.647; P = 0.005). AT2R expression positively correlated with AGT (r = 0.615, P = 0.002) in the pre-eclamptic placentae only. The raised AT1R expression in pre-eclampsia, together with inadequate antioxidant protection, possibly through lower GPx activity, might enhance the vasoconstrictor effect of locally-generated AngII, contributing to the restricted fetal growth characteristic of pre-eclampsia. Conversely, the AT2R:AGT association within the pre-eclamptic placenta may provide a compensatory mechanism. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Dysregulation of the renin-angiotensin system during lung ischemia-reperfusion injury.

    Science.gov (United States)

    Kehoe, K; Gielis, J F; Vliegen, G; Van Elzen, R; Verkerk, R; Driessens, E; Domen, A; Lambeir, A M; Maes, L; Cos, P; De Meester, I; Van Schil, P E Y

    2016-08-01

    Aim/Purpose of the Study: Activation of the renin-angiotensin system leading to increased angiotensin-(1-7) (Ang-(1-7)) and decreased angiotensin 2 (Ang 2) levels may be a new therapeutic approach to reduce acute lung injury. Prolylcarboxypeptidase (PRCP) and prolyloligopeptidase (PREP) are capable of hydrolyzing Ang 2 into Ang-(1-7). However, their relation with circulating Ang 2 levels after lung ischemia-reperfusion injury (LIRI) has never been explored. This study determines whether the activity and expression of PRCP and PREP in plasma and lung tissue is related to circulating Ang 2 levels in a murine model of LIRI. LIRI in Swiss mice (6 animals per group) was induced by temporary left lung hilar clamping (1 h) followed by 0, 1 or 24 h of reperfusion. Animals in the sham group received thoracotomy only. PRCP activity was measured via RP-HPLC, PREP activity using a fluorogenic substrate and plasma Ang 2 levels via ELISA. Western blotting was used to determine the PRCP and PREP protein expression profiles in left lung tissue. Plasma Ang 2 levels significantly rise after lung ischemia and remain increased after 1 h and 24 h of reperfusion compared to the sham group. While a significant decrease in plasma PREP activity was found after 24 h of reperfusion, a transient increase in plasma PRCP activity was observed after ischemia. However, no correlation with plasma Ang 2 levels could be demonstrated. The activity profiles of PRCP and PREP and the protein expression of PRCP in the lung tissues remained unchanged after LIRI. LIRI causes a dysregulation of circulating Ang 2 levels and plasma PREP activity, although no direct link between both phenomena could be shown. The activity profile of pulmonary PRCP and PREP was not significantly changed after LIRI, which implies a minor role for local PRCP and PREP in the ischemic lung itself.

  10. No significant effect of angiotensin II receptor blockade on intermediate cardiovascular end points in hemodialysis patients

    DEFF Research Database (Denmark)

    Peters, Christian D; Kjaergaard, Krista D; Jensen, Jens D

    2014-01-01

    points such as central aortic blood pressure, carotid-femoral pulse wave velocity, left ventricular mass index, N-terminal brain natriuretic prohormone, heart rate variability, and plasma catecholamines were not significantly affected by irbesartan treatment. Changes in systolic blood pressure during......Agents blocking the renin-angiotensin-aldosterone system are frequently used in patients with end-stage renal disease, but whether they exert beneficial cardiovascular effects is unclear. Here the long-term effects of the angiotensin II receptor blocker, irbesartan, were studied in hemodialysis......, and residual renal function. Brachial blood pressure decreased significantly in both groups, but there was no significant difference between placebo and irbesartan. Use of additional antihypertensive medication, ultrafiltration volume, and dialysis dosage were not different. Intermediate cardiovascular end...

  11. Moderation of dietary sodium potentiates the renal and cardiovascular protective effects of angiotensin receptor blockers

    DEFF Research Database (Denmark)

    Lambers Heerspink, Hiddo J; Holtkamp, Frank A; Parving, Hans-Henrik

    2012-01-01

    Dietary sodium restriction has been shown to enhance the short-term response of blood pressure and albuminuria to angiotensin receptor blockers (ARBs). Whether this also enhances the long-term renal and cardiovascular protective effects of ARBs is unknown. Here we conducted a post-hoc analysis...... of the RENAAL and IDNT trials to test this in patients with type 2 diabetic nephropathy randomized to ARB or non-renin-angiotensin-aldosterone system (non-RAASi)-based antihypertensive therapy. Treatment effects on renal and cardiovascular outcomes were compared in subgroups based on dietary sodium intake...... during treatment, measured as the 24-h urinary sodium/creatinine ratio of 1177 patients with available 24-h urinary sodium measurements. ARB compared to non-RAASi-based therapy produced the greatest long-term effects on renal and cardiovascular events in the lowest tertile of sodium intake. Compared...

  12. Reduced baroreflex sensitivity in alcoholic cirrhosis: relations to hemodynamics and humoral systems

    DEFF Research Database (Denmark)

    Møller, Søren; Iversen, Jens S; Henriksen, Jens H

    2007-01-01

    In cirrhosis, arterial vasodilatation leads to central hypovolemia and activation of the sympathetic nervous and renin-angiotensin-aldosterone systems. As the liver disease and circulatory dysfunction may affect baroreflex sensitivity (BRS), we assessed BRS in a large group of patients with cirrh...

  13. Severe hypoglycaemia in type 1 diabetes: impact of the renin-angiotensin system and other risk factors

    DEFF Research Database (Denmark)

    Pedersen-Bjergaard, Ulrik

    2009-01-01

    this thesis was conducted to assess the significance of severe hypoglycaemia as a clinical problem in the type 1 diabetic population, to evaluate the impact of known risk factors on occurrence of severe hypoglycaemia, and to identify new markers that could contribute to improved prediction of, and inspire...... targets and thereby open for prevention of severe hypoglycaemia. Furthermore, subjects with elevated renin-angiotensin system activity and a high rate of severe hypoglycaemia might benefit from pharmacological blockade of the renin-angiotensin system by ACE inhibitors or angiotensin II receptor blockers...... diabetes. The series of studies that constitute this thesis was conducted to assess the significance of severe hypoglycaemia as a clinical problem in the type 1 diabetic population, to evaluate the impact of known risk factors on occurrence of severe hypoglycaemia, and to identify new markers that could...

  14. A Study on Renin-Angiotensin System and Total Exchangeable Sodium in Hypertension

    International Nuclear Information System (INIS)

    Choe, Kang Won; Park, Jung Sik; Lee, Jung Sang; Koh, Chang Soon

    1976-01-01

    The etiologic role of renin-angiotensin system and sodium-volume status in the pathophysiology of various forms of hypertension was investigated. Plasma renin activity (PRA) was measured by radioimmunoassay, while sodium-volume status was evaluated by the determination of total exchangeable sodium(NaE) using isotope dilution method. The subjects consisted of 25 controls, 24 patients with essential hypertension, 22 patients with chronic renal failure (13 with hypertension, 9 without hypertension) and 14 patients with malignant hypertension. The results were as follows: 1) An inverse correlation between NaE and PRA was noted in control subjects (r=-0.598, p 0.1) 3) Absolute value of PRA was not deviated significantly from control group (2.53±1.416 ng/ml/hr) except in malignant hypertension (6.09±2.042, p 0.1). It is suggested that renin-angiotensin system plays a predominant role in the pathogenesis of malignant hypertension and in hypertension of chronic renal failure, though sodium retention is also contributing factor. PRA variation in essential hypertension does not appear to be associated with any consistent change in Na-volume status, suggesting the existence of another mechanism in the genesis of hypertension and PRA variation.

  15. Involvement of renin-angiotensin system in hypertensive effect of cadmium in rats.

    Science.gov (United States)

    Lall, S B; Peshin, S S; Gulati, K; Khattar, S; Das, N; Seth, S D

    1997-04-01

    Role of renin-angiotensin system in hypertension induced by cadmium chloride (CdCl2) in rats has been investigated. Intravenous administration of CdCl (1 mg/kg) produced a biphasic response i.e. a transient fall followed by a marked and consistent rise in blood pressure. The peak hypertensive effect was accompanied by raised PRA levels. Pretreatment with captopril (1 mg/kg, i.v.) losartan (1 mg/kg, i.v.) or captopril + losartan attenuated the pressor response to Cd by 62%, 42% and 100% respectively in separate groups. Central administration of Cd (10 micrograms/rat, i.c.v.) showed a biphasic response similar to that observed after i.v. route. However, it was not accompanied by raised PRA levels. Prior treatment with losartan (10 micrograms/rat, i.c.v.) completely abolished the pressor response to Cd (i.c.v.) whereas it was not affected significantly by captopril (10 micrograms/rat, i.c.v.). On the other hand, centrally administered losartan only partially reduced the pressor response to i.v. Cd. The results are discussed in light of a differential involvement of central vs peripheral renin-angiotensin system in the hypertensive effect of Cd.

  16. Dietary Sodium Suppresses Digestive Efficiency via the Renin-Angiotensin System.

    Science.gov (United States)

    Weidemann, Benjamin J; Voong, Susan; Morales-Santiago, Fabiola I; Kahn, Michael Z; Ni, Jonathan; Littlejohn, Nicole K; Claflin, Kristin E; Burnett, Colin M L; Pearson, Nicole A; Lutter, Michael L; Grobe, Justin L

    2015-06-11

    Dietary fats and sodium are both palatable and are hypothesized to synergistically contribute to ingestive behavior and thereby obesity. Contrary to this hypothesis, C57BL/6J mice fed a 45% high fat diet exhibited weight gain that was inhibited by increased dietary sodium content. This suppressive effect of dietary sodium upon weight gain was mediated specifically through a reduction in digestive efficiency, with no effects on food intake behavior, physical activity, or resting metabolism. Replacement of circulating angiotensin II levels reversed the effects of high dietary sodium to suppress digestive efficiency. While the AT1 receptor antagonist losartan had no effect in mice fed low sodium, the AT2 receptor antagonist PD-123,319 suppressed digestive efficiency. Correspondingly, genetic deletion of the AT2 receptor in FVB/NCrl mice resulted in suppressed digestive efficiency even on a standard chow diet. Together these data underscore the importance of digestive efficiency in the pathogenesis of obesity, and implicate dietary sodium, the renin-angiotensin system, and the AT2 receptor in the control of digestive efficiency regardless of mouse strain or macronutrient composition of the diet. These findings highlight the need for greater understanding of nutrient absorption control physiology, and prompt more uniform assessment of digestive efficiency in animal studies of energy balance.

  17. Maternal Gestational Hypertension-Induced Sensitization of Angiotensin II Hypertension Is Reversed by Renal Denervation or Angiotensin-Converting Enzyme Inhibition in Rat Offspring.

    Science.gov (United States)

    Xue, Baojian; Yin, Haifeng; Guo, Fang; Beltz, Terry G; Thunhorst, Robert L; Johnson, Alan Kim

    2017-04-01

    Numerous findings demonstrate that there is a strong association between maternal health during pregnancy and cardiovascular disease in adult offspring. The purpose of the present study was to test whether maternal gestational hypertension modulates brain renin-angiotensin-aldosterone system (RAAS) and proinflammatory cytokines that sensitizes angiotensin II-elicited hypertensive response in adult offspring. In addition, the role of renal nerves and the RAAS in the sensitization process was investigated. Reverse transcription polymerase chain reaction analyses of structures of the lamina terminalis and paraventricular nucleus indicated upregulation of mRNA expression of several RAAS components and proinflammatory cytokines in 10-week-old male offspring of hypertensive dams. Most of these increases were significantly inhibited by either renal denervation performed at 8 weeks of age or treatment with an angiotensin-converting enzyme inhibitor, captopril, in drinking water starting at weaning. When tested beginning at 10 weeks of age, a pressor dose of angiotensin II resulted in enhanced upregulation of mRNA expression of RAAS components and proinflammatory cytokines in the lamina terminalis and paraventricular nucleus and an augmented pressor response in male offspring of hypertensive dams. The augmented blood pressure change and most of the increases in gene expression in the offspring were abolished by either renal denervation or captopril. The results suggest that maternal hypertension during pregnancy enhances pressor responses to angiotensin II through overactivity of renal nerves and the RAAS in male offspring and that upregulation of the brain RAAS and proinflammatory cytokines in these offspring may contribute to maternal gestational hypertension-induced sensitization of the hypertensive response to angiotensin II. © 2017 American Heart Association, Inc.

  18. Angiotensin receptor-neprilysin inhibitors: clinical potential in heart failure and beyond

    Directory of Open Access Journals (Sweden)

    Singh JSS

    2015-06-01

    Full Text Available Jagdeep SS Singh, Chim C Lang Division of Cardiovascular and Diabetes Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK Abstract: Heart failure remains a major concern across the globe as life expectancies and delivery of health care continue to improve. There has been a dearth of new developments in heart failure therapies in the last decade until last year, with the release of the results from the PARADIGM-HF Trial heralding the arrival of a promising new class of drug, ie, the angiotensin receptor-neprilysin inhibitor. In this review, we discuss the evolution of our incremental understanding of the neurohormonal mechanisms involved in the pathophysiology of heart failure, which has led to our success in modulating its various pathways. We start by examining the renin-angiotensin-aldosterone system, followed by the challenges of modulating the natriuretic peptide system. We then delve deeper into the pharmacology and mechanisms by which angiotensin receptor-neprilysin inhibitors achieve their significant cardiovascular benefits. Finally, we also consider the potential application of this new class of drug in other areas, such as heart failure with preserved ejection fraction, hypertension, patients with renal impairment, and following myocardial infarction. Keywords: heart failure, angiotensin receptor-neprilysin inhibitor, heart failure with preserved ejection fraction, nesiritide, candoxatril, omapatrilat, hypertension, renal impairment, myocardial infarction

  19. Epistatic effects of polymorphisms in genes from the renin-angiotensin, bradykinin, and fibrinolytic systems on plasma t-PA and PAI-1 levels

    NARCIS (Netherlands)

    Asselbergs, Folkert W.; Williams, Scott M.; Hebert, Patricia R.; Coffey, Christopher S.; Hillege, Hans L.; Navis, Gerjan; Vaughan, Douglas E.; van Gilst, Wiek H.; Moore, Jason H.

    Tissue plasminogen activator (t-PA) and plasminogen activator inhibitor 1 (PAI-1) directly influence thrombus formation and degradation and thereby risk for arterial thrombosis. Activation of the renin-angiotensin system has been linked to the production of PAI-1 expression via the angiotensin II

  20. Palmitoylethanolamide treatment reduces blood pressure in spontaneously hypertensive rats: involvement of cytochrome p450-derived eicosanoids and renin angiotensin system.

    Directory of Open Access Journals (Sweden)

    Giuseppina Mattace Raso

    Full Text Available Palmitoylethanolamide (PEA, a peroxisome proliferator-activated receptor-α agonist, has been demonstrated to reduce blood pressure and kidney damage secondary to hypertension in spontaneously hypertensive rat (SHR. Currently, no information is available concerning the putative effect of PEA on modulating vascular tone. Here, we investigate the mechanisms underpinning PEA blood pressure lowering effect, exploring the contribution of epoxyeicosatrienoic acids, CYP-dependent arachidonic acid metabolites, as endothelium-derived hyperpolarizing factors (EDHF, and renin angiotensin system (RAS modulation. To achieve this aim SHR and Wistar-Kyoto rats were treated with PEA (30 mg/kg/day for five weeks. Functional evaluations on mesenteric bed were performed to analyze EDHF-mediated vasodilation. Moreover, mesenteric bed and carotid were harvested to measure CYP2C23 and CYP2J2, the key isoenzymes in the formation of epoxyeicosatrienoic acids, and the soluble epoxide hydrolase, which is responsible for their degradation in the corresponding diols. Effect of PEA on RAS modulation was investigated by analyzing angiotensin converting enzyme and angiotensin receptor 1 expression. Here, we showed that EDHF-mediated dilation in response to acetylcholine was increased in mesenteric beds of PEA-treated SHR. Western blot analysis revealed that the increase in CYP2C23 and CYP2J2 observed in SHR was significantly attenuated in mesenteric beds of PEA-treated SHR, but unchanged in the carotids. Interestingly, in both vascular tissues, PEA significantly decreased the soluble epoxide hydrolase protein level, accompanied by a reduced serum concentration of its metabolite 14-15 dihydroxyeicosatrienoic acid, implying a reduction in epoxyeicosatrienoic acid hydrolisis. Moreover, PEA treatment down-regulated angiotensin receptor 1 and angiotensin converting enzyme expression, indicating a reduction in angiotensin II-mediated effects. Consistently, a damping of the

  1. The renin-angiotensin system in malignant hypertension revisited: plasma renin activity, microangiopathic hemolysis, and renal failure in malignant hypertension

    NARCIS (Netherlands)

    van den Born, Bert-Jan H.; Koopmans, Richard P.; van Montfrans, Gert A.

    2007-01-01

    BACKGROUND: Malignant hypertension is a renin-dependent form of hypertension. However, the variations in renin-angiotensin system (RAS) activation in malignant hypertension are not completely understood. A proposed mechanism for ongoing RAS activation is the presence of microangiopathic hemolysis

  2. Individual titration for maximal blockade of the renin-angiotensin system in proteinuric patients: A feasible strategy?

    NARCIS (Netherlands)

    Vogt, Liffert; Navis, Ger Jan; de Zeeuw, Dick

    2005-01-01

    Agents that interfere with the renin-angiotensin system (RAS) reduce proteinuria and afford renal protection. The combination of different measures that serve maximization of RAS blockade is thought to improve the antiproteinuric efficacy. The feasibility and the efficacy of such a combination

  3. Individual titration for maximal blockade of the renin-angiotensin system in proteinuric patients: a feasible strategy?

    NARCIS (Netherlands)

    Vogt, Liffert; Navis, Gerjan; de Zeeuw, Dick

    2005-01-01

    Agents that interfere with the renin-angiotensin system (RAS) reduce proteinuria and afford renal protection. The combination of different measures that serve maximization of RAS blockade is thought to improve the antiproteinuric efficacy. The feasibility and the efficacy of such a combination

  4. Cardiac remodeling during and after renin-angiotensin system stimulation in Cyp1a1-Ren2 transgenic rats

    DEFF Research Database (Denmark)

    Heijnen, Bart Fj; Pelkmans, Leonie Pj; Danser, Ah Jan

    2013-01-01

    This study investigated renin-angiotensin system (RAS)-induced cardiac remodeling and its reversibility in the presence and absence of high blood pressure (BP) in Cyp1a1-Ren2 transgenic inducible hypertensive rats (IHR). In IHR (pro)renin levels and BP can be dose-dependently titrated by oral...

  5. Elevated pulmonary arterial and systemic plasma aldosterone levels associate with impaired cardiac reserve capacity during exercise in left ventricular systolic heart failure patients: A pilot study.

    Science.gov (United States)

    Maron, Bradley A; Stephens, Thomas E; Farrell, Laurie A; Oldham, William M; Loscalzo, Joseph; Leopold, Jane A; Lewis, Gregory D

    2016-03-01

    Elevated levels of aldosterone are a modifiable contributor to clinical worsening in heart failure with reduced ejection fraction (HFrEF). Endothelin-1 (ET-1), which is increased in HFrEF, induces pulmonary endothelial aldosterone synthesis in vitro. However, whether transpulmonary aldosterone release occurs in humans or aldosterone relates to functional capacity in HFrEF is not known. Therefore, we aimed to characterize ET-1 and transpulmonary aldosterone levels in HFrEF and determine if aldosterone levels relate to peak volume of oxygen uptake (pVO2). Data from 42 consecutive HFrEF patients and 18 controls referred for invasive cardiopulmonary exercise testing were analyzed retrospectively. Radial ET-1 levels (median [interquartile range]) were higher in HFrEF patients compared with controls (17.5 [11.5-31.4] vs 11.5 [4.4-19.0] pg/ml, p = 0.04). A significant ET-1 transpulmonary gradient (pulmonary arterial [PA] - radial arterial levels) was present in HFrEF (p reserve capacity in HFrEF. Published by Elsevier Inc.

  6. Downregulation of angiotensin II type 1 receptors during sepsis.

    Science.gov (United States)

    Bucher, M; Ittner, K P; Hobbhahn, J; Taeger, K; Kurtz, A

    2001-08-01

    Our study aimed to characterize the mechanisms underlying the attenuated cardiovascular responsiveness toward the renin-angiotensin system during sepsis. For this purpose, we determined the effects of experimental Gram-negative and Gram-positive sepsis in rats. We found that sepsis led to a ubiquitous upregulation of NO synthase isoform II expression and to pronounced hypotension. Despite increased plasma renin activity and plasma angiotensin (Ang) II levels, plasma aldosterone concentrations were normal, and the blood pressure response to exogenous Ang II was markedly diminished in septic rats. Mimicking the fall of blood pressure during sepsis by short-term infusion of the NO donor sodium nitroprusside in normal rats did not alter their blood pressure response to exogenous Ang II. Therefore, we considered the possibility of an altered expression of Ang II receptors during sepsis. It turned out that Ang II type 1 receptor expression was markedly downregulated in all organs of septic rats. Further in vitro studies with rat renal mesangial cells showed that NO and a combination of proinflammatory cytokines (interleukin-1beta, tumor necrosis factor-alpha, and interferon-gamma) downregulated Ang II type 1 receptor expression in a synergistic fashion. In summary, our data suggest that sepsis causes a systemic downregulation of Ang II type 1 receptors that is likely mediated by proinflammatory cytokines and NO. We suggest that this downregulation of Ang II type 1 receptors is the main reason for the attenuated responsiveness of blood pressure and of aldosterone formation to Ang II and, therefore, contributes to the characteristic septic shock.

  7. Aldosterone synthase gene is not a major susceptibility gene for progression of chronic kidney disease in patients with autosomal dominant polycystic kidney disease

    Directory of Open Access Journals (Sweden)

    Gnanasambandan Ramanathan

    2017-01-01

    Full Text Available Autosomal dominant polycystic kidney disease (ADPKD is the most common heritable kidney disease and is characterized by bilateral renal cysts. Hypertension is a frequent cause of chronic kidney disease (CKD and mortality in patients with ADPKD. The aldosterone synthase gene polymorphisms of the renin-angiotensin-aldosterone system have been extensively studied as hypertension candidate genes. The present study is aimed to investigate the potential modifier effect of CYP11B2 gene on the progression of CKD in ADPKD. One hundred and two ADPKD patients and 106 healthy controls were recruited based on Ravine inclusion and exclusion criteria. The three tag-SNPs within CYP11B2 gene (rs3802230, rs4543, and rs4544 were genotyped using FRET-based KASPar method. Cochran-Armitage trend test was used to assess the potential associations between these polymorphisms and CKD stages. Mantel- Haenszel stratified analysis was used to explore confounding and interaction effects of these polymorphisms. Of the three tag-SNPs genotyped, rs4544 polymorphism was monomorphic and rs3802230 deviated Hardy-Weinberg equilibrium. The CYP11B2 tag-SNPs did not show significant association with ADPKD or CKD. Further, these polymorphisms did not exhibit confounding effect on the relationship between CKD progression and hypertension. Our results suggest that aldosterone synthase gene is not a major susceptibility gene for progression of CKD in South Indian ADPKD patients.

  8. Role of calcium in effects of atrial natriuretic peptide on aldosterone production in adrenal glomerulosa cells

    International Nuclear Information System (INIS)

    Chartier, L.; Schiffrin, E.L.

    1987-01-01

    Atrial natriuretic peptide (ANP) inhibits the stimulation of aldosterone secretion by isolated adrenal glomerulosa cells produced by angiotensin II (ANG II), ACTH, and potassium. The effect of ANP on the dose-response curve of aldosterone stimulated by ANG II, ACTH, and potassium on isolated rat adrenal glomerulosa cells was studied. In the presence of ANP the maximal response of aldosterone output stimulated by ANG II or potassium decreased and the half-maximum (EC 50 ) of the response to ACTH was displaced to the right. Because these effects resemble those of calcium-channel blockers, the authors investigated the effect of different concentrations of nifedipine, a dihydropyridine calcium-channel blocker, on the dose-response curve of aldosterone stimulated by ANG II, ACTH, and potassium. Nifedipine produced effects similar to ANP. The maximal response of aldosterone stimulated by ANG II and potassium was decreased and the dose-response curve to ACTH was displaced to the right. ANP decreased the maximal response of aldosterone to the dihydropyridine derivative BAY K8644, a calcium-channel activator, without change in its EC 50 . In contrast, nifedipine displaced the dose-response curve to BAY K8644 to the right as expected of a competitive inhibitor. The effect of ANP and nifedipine on basal and stimulated 45 Ca influx into isolated rat adrenal glomerulosa cells was studied. ANP may act on the rat adrenal glomerulosa cells at least in part by interference with calcium entry

  9. Sex differences in angiotensin II-stimulated fluid intake.

    Science.gov (United States)

    Santollo, Jessica

    2017-11-01

    What is the topic of this review? This report describes sex differences in the responses to angiotensin II, with a focus on fluid intake. What advances does it highlight? There are conflicting reports on the direction of the sex difference in fluid intake in response to angiotensin II. This review highlights how accounting for differences in body weight contributes to the discrepancies in the literature. In certain conditions, body weight influences fluid intake in a sex-specific manner. This review also highlights the divergent effects of oestrogen receptor activation on fluid intake, which are likely to underlie the discussed sex differences. Sex has a clear effect on the renin-angiotensin-aldosterone system. Although sex differences in the pressor response to angiotensin II (Ang II) are well established, understanding of the sex differences in the fluid intake response to Ang II is clouded by conflicting reports. Here, I suggest that accounting for differences in body weight contributes to the discrepancies in the literature. Our recent findings demonstrate that body weight influences Ang II-stimulated water intake in certain conditions in male, but not in female rats. When differences in body weight are corrected for in the appropriate circumstances, we found that males consume more water in response to Ang II compared with females. Males and females also show differences in drinking microstructure, i.e. bottle spout lick patterns, which provide clues into the mechanism(s) underlying this sex difference. Oestrogens, which inhibit Ang II-stimulated fluid intake and circulate at higher concentrations in females, are likely to contribute to this sex difference. This review also discusses the diversity in oestrogen signalling via multiple oestrogen receptor subtypes, which selectively inhibit Ang II-stimulated fluid intake. © 2017 The Authors. Experimental Physiology © 2017 The Physiological Society.

  10. Angiotensin receptor-binding molecule in leukocytes in association with the systemic and leukocyte inflammatory profile.

    Science.gov (United States)

    Haruhara, Kotaro; Wakui, Hiromichi; Azushima, Kengo; Kurotaki, Daisuke; Kawase, Wataru; Uneda, Kazushi; Haku, Sona; Kobayashi, Ryu; Ohki, Kohji; Kinguchi, Sho; Ohsawa, Masato; Minegishi, Shintaro; Ishigami, Tomoaki; Matsuda, Miyuki; Yamashita, Akio; Nakajima, Hideaki; Tamura, Tomohiko; Tsuboi, Nobuo; Yokoo, Takashi; Tamura, Kouichi

    2018-02-01

    The components of the renin-angiotensin system in leukocytes is involved in the pathophysiology of non-communicable diseases (NCDs), including hypertension, atherosclerosis and chronic kidney disease. Angiotensin II type 1 receptor (AT1R)-associated protein (ATRAP) is an AT1R-specific binding protein, and is able to inhibit the pathological activation of AT1R signaling in certain animal models of NCDs. The aim of the present study was to investigate the expression and regulation of ATRAP in leukocytes. Human leukocyte ATRAP mRNA was measured with droplet digital polymerase chain reaction system, and analyzed in relation to the clinical variables. We also examined the leukocyte cytokines mRNA in bone-marrow ATRAP-deficient and wild-type chimeric mice after injection of low-dose lipopolysaccharide. The ATRAP mRNA was abundantly expressed in leukocytes, predominantly granulocytes and monocytes, of healthy subjects. In 86 outpatients with NCDs, leukocyte ATRAP mRNA levels correlated positively with granulocyte and monocyte counts and serum C-reactive protein levels. These positive relationships remained significant even after adjustment. Furthermore, the leukocyte ATRAP mRNA was significantly associated with the interleukin-1β, tumor necrosis factor-α and monocyte chemotactic protein-1 mRNA levels in leukocytes of NCDs patients. In addition, the leukocyte interleukin-1β mRNA level was significantly upregulated in bone marrow ATRAP-deficient chimeric mice in comparison to wild-type chimeric mice after injection of lipopolysaccharide. These results suggest that leukocyte ATRAP is an emerging marker capable of reflecting the systemic and leukocyte inflammatory profile, and plays a role as an anti-inflammatory factor in the pathophysiology of NCDs. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Primary Aldosteronism: Changing Definitions and New Concepts of Physiology and Pathophysiology Both Inside and Outside the Kidney.

    Science.gov (United States)

    Stowasser, Michael; Gordon, Richard D

    2016-10-01

    In the 60 years that have passed since the discovery of the mineralocorticoid hormone aldosterone, much has been learned about its synthesis (both adrenal and extra-adrenal), regulation (by renin-angiotensin II, potassium, adrenocorticotrophin, and other factors), and effects (on both epithelial and nonepithelial tissues). Once thought to be rare, primary aldosteronism (PA, in which aldosterone secretion by the adrenal is excessive and autonomous of its principal regulator, angiotensin II) is now known to be the most common specifically treatable and potentially curable form of hypertension, with most patients lacking the clinical feature of hypokalemia, the presence of which was previously considered to be necessary to warrant further efforts towards confirming a diagnosis of PA. This, and the appreciation that aldosterone excess leads to adverse cardiovascular, renal, central nervous, and psychological effects, that are at least partly independent of its effects on blood pressure, have had a profound influence on raising clinical and research interest in PA. Such research on patients with PA has, in turn, furthered knowledge regarding aldosterone synthesis, regulation, and effects. This review summarizes current progress in our understanding of the physiology of aldosterone, and towards defining the causes (including genetic bases), epidemiology, outcomes, and clinical approaches to diagnostic workup (including screening, diagnostic confirmation, and subtype differentiation) and treatment of PA. Copyright © 2016 the American Physiological Society.

  12. Dual renin-angiotensin system blockade at optimal doses for proteinuria

    NARCIS (Netherlands)

    Laverman, GD; Navis, G; Henning, RH; de Jong, PE; dE Zeeuw, D

    Background. The antiproteinuric effect of combining the angiotensin-converting enzyme (ACE) inhibitor lisinopril and the angiotensin II (Ang II) antagonist losartan was compared to that of the optimal antiproteinuric doses of monotherapy. Methods. To this purpose, lisinopril and losartan were

  13. Systemic vascular resistance during brief withdrawal of angiotensin converting enzyme inhibition in heart failure

    DEFF Research Database (Denmark)

    Gabrielsen, A; Bie, P; Christensen, N J

    2002-01-01

    We tested the hypothesis that moderate increases in endogenous angiotensin II (Ang II) concentrations, induced by withdrawal of angiotensin converting enzyme inhibition (ACE-I) in patients with compensated heart failure (HF) on chronic medical therapy, do not increase or impair control of systemi...

  14. Current aspects of the interactions between dementia, the brain renin-angiotensin system and oxidative stress

    Directory of Open Access Journals (Sweden)

    Serban Dragomir

    2015-01-01

    Full Text Available There is increased interest in the interactions between vascular disorders and Alzheimer’s disease (AD. While initially these interactions were explained by the fact that these are both very common disorders, particularly later in life, recently, the possibility that these deficiencies might actually coexist is increasingly being questioned. This review attempts to present modern aspects and current reports regarding the interactions between AD, the renin-angiotensin system (RAS and hypertension, while also describing the relevance of antihypertensive drug use acting via the RAS in the treatment and prevention of AD, as well as the importance of oxidative stress, the alteration of the balance between antioxidants and pro-oxidants, in the interaction between AD and the RAS.

  15. Role of the inhibitors of angiotensin renin system on the DNA integrity of irradiated spermatozoids

    International Nuclear Information System (INIS)

    Spadella, Maria A.; Mansano, Naira S.; Schwarz, Franciele C.; Viani, Gustavo A.; Chies, Agnaldo B.

    2016-01-01

    Radiation action in the testes can significantly affect the reproductive capacity due to oxidative stress generated; phenomenon in which there is evidence of involvement of the Renin Angiotensin System (RAS). This study evaluated the role of AT1 receptor inhibitors, in mitigating the radioinduced DNA damage sperm from semen samples left vas deferens. Male Wistar rats were divided into six experimental groups: Control, 5Gy, Telmisartan (12mg/kg/day) and Losartan (34mg/kg/2x/day), 5 Gy + Telmisartan and 5 Gy + Losartan. The results showed increase in the percentage of sperm with fragmented DNA in irradiated groups when compared to controls, which was not reversed in the irradiated and treated groups. The radiation of 5Gy (single dose) affected the DNA-protein complex of the sperm and the treatments did not influence in reversing this damage, considering the experimental protocol used. (author)

  16. Blockade of Rennin-Angiotensin system blunts the fibrotic response in experimental acute pyelonephritis

    Directory of Open Access Journals (Sweden)

    Singal A

    2005-01-01

    Full Text Available Aim: To study the impact of Renin-Angiotensin system blockade in experimental acute pyelonephritis, induced by a novel surgical approach via dorsal lumbotomy incision. Materials and Methods : 45 Adult female WISTAR rats aged 8-12 weeks, underwent direct inoculation of 0.1 ml of E.coli suspension into the parenchyma of the surgically exposed kidney. 3 groups of rats were studied: Group A - treated with antibiotics only; Group B- Captopril and antibiotics and Group C- Losartan and antibiotics. Changes of acute inflammation, parenchymal destruction and scarring were compared between the groups on histopathological sections. Kruskal-Wallis test was used for statistical analysis. Results : Changes consistent with acute pyelonephritis were seen in all the kidneys. Mean% scar area in Group A, Group B and Group C was 37.08±1.79, 24.40±1.88 and 24.68±1.32% respectively at end of six weeks. Mean tubular density in Group A, B and C was 17.26±1.92, 47.18±3.00 and 47.00±5.08-tubules/lac mm2 respectively. The differences between the control and the treated animals were significant, though the results did not differ between the losartan and captopril treated rats. Conclusions : Dorsal lumbotomy approach to the kidney provides a good exposure of the kidney. Induction of acute pyelonephritis by direct inoculation of bacteria into renal cortex produced a consistent scar at 6 weeks. Blockade of renin angiotensin system by either captopril or losartan decreased the renal scar area by almost 1/3 at 6 weeks.

  17. The renin-angiotensin system in conscious newborn sheep: metabolic clearance rate and activity.

    Science.gov (United States)

    Velaphi, Sithembiso C; Despain, Kevin; Roy, Timothy; Rosenfeld, Charles R

    2007-06-01

    The role of the renin-angiotensin system (RAS) in regulating newborn mean arterial blood pressure (MAP) and tissue blood flow remains unclear. Although postnatal MAP increases, vascular responsiveness to infused angiotensin II (ANG II) is unchanged, possibly reflecting increased metabolic clearance rate of ANG II (MCR(ANG II)). To address this, we examined MAP, heart rate, plasma ANG II and renin activity (PRA), and MCR(ANG II) in conscious postnatal sheep (n = 9, 5-35 d old) before and during continuous systemic ANG II infusions to measure MCR (ANG II). Postnatal MAP increased (p < 0.02), whereas plasma ANG II decreased from 942 +/- 230 (SEM) to 471 +/- 152 and 240 +/- 70 pg/mL at <10 d, 10-20 d, and 21-35 d postnatally (p = 0.05), respectively. Despite high plasma ANG II, PRA remained elevated, averaging 6.70 +/- 1.1 ng/mL.h throughout the postnatal period, but decreased 35% (p = 0.01) during ANG II infusions. MCR(ANG II) decreased approximately sixfold after birth and averaged 115 mL/min.kg during the first month. Circulating ANG II is markedly increased after birth, reflecting placental removal, high fetal MCR(ANG II), and enhanced RAS activity. Although circulating ANG II decreases as MAP increases, MCR(ANG II) is unchanged, suggesting decreased ANG II production. Persistent vascular smooth muscle (VSM) AT2 receptor subtype (AT2R) expression after birth may modify the hypertensive effects of ANG II postnatally.

  18. Addition of hydrochlorothiazide to angiotensin receptor blocker therapy can achieve a lower sodium balance with no acceleration of intrarenal renin angiotensin system in patients with chronic kidney disease.

    Science.gov (United States)

    Fuwa, Daisuke; Fukuda, Michio; Ogiyama, Yoshiaki; Sato, Ryo; Mizuno, Masashi; Miura, Toshiyuki; Abe-Dohmae, Sumiko; Michikawa, Makoto; Kobori, Hiroyuki; Ohte, Nobuyuki

    2016-01-01

    Angiotensin receptor blockers (ARBs) produce a lower sodium (Na) balance, and the natriuretic effect is enhanced under Na deprivation, despite falls in blood pressure (BP) and glomerular filtration rate (GFR). The effect of additional hydrochlorothiazide (HCTZ; 12.5 mg/day) to ARB treatment (valsartan; 80 mg/day) on glomerulotubular Na balance was evaluated in 23 patients with chronic kidney disease. Add-on HCTZ decreased GFR, tubular Na load, and tubular Na reabsorption (t(Na)), although 24-hour urinary Na excretion (U(Na)V) remained constant. Daily urinary angiotensinogen excretion (U(AGT)V, 152±10→82±17 μg/g Cre) reduced (p=0.02). Changes in tubular Na load (r(2)=0.26) and t(Na) (r(2)=0.25) correlated with baseline 24-hour U(AGT)V. Changes in filtered Na load correlated with changes in nighttime systolic BP (r(2)=0.17), but not with changes in daytime systolic BP. The change in the t(Na) to filtered Na load ratio was influenced by the change in daytime U(Na)V (β=-0.67, F=16.8), rather than the change in nighttime U(Na)V. Lower Na balance was produced by add-on HCTZ to ARB treatment without an increase of intra-renal renin-angiotensin system activity, leading to restoration of nocturnal hypertension. A further study is needed to demonstrate that the reduction of U(AGT)V by additional diuretics to ARBs prevents the progression of nephropathy or cardiovascular events. © The Author(s) 2016.

  19. Leptin Mediate High Fat Diet Sensitization of Angiotensin II-elicited Hypertension by Upregulating the Brain Renin-Angiotensin System and Inflammation

    Science.gov (United States)

    Xue, Baojian; Yu, Yang; Zhang, Zhongming; Guo, Fang; Beltz, Terry G.; Thunhorst, Robert L.; Felder, Robert B.; Johnson, Alan Kim

    2016-01-01

    Obesity is characterized by increased circulating levels of the adipocyte-derived hormone leptin, which can increase sympathetic nerve activity and raise blood pressure. A previous study revealed that rats fed a high fat diet (HFD) have an enhanced hypertensive response to subsequent angiotensin (Ang) II administration that is mediated at least in part by increased activity of brain renin-angiotensin system (RAS) and proinflammatory cytokines (PICs). The present study tested whether leptin mediates this HFD-induced sensitization of Ang II-elicited hypertension by interacting with brain RAS and PICs mechanisms. Rats fed a HFD for 3 weeks had significant increases in white adipose tissue mass, plasma leptin levels and mRNA expression of leptin and its receptors in the lamina terminalis (LT) and hypothalamic paraventricular nucleus (PVN). Central infusion of a leptin receptor antagonist during HFD feeding abolished HFD sensitization of Ang II-elicited hypertension. Furthermore, central infusion of leptin mimicked the sensitizing action of HFD. Concomitant central infusions of the AT1-R antagonist irbesartan, the TNF-α synthesis inhibitor pentoxifylline, or the inhibitor of microglial activation minocycline prevented the sensitization produced by central infusion of leptin. RT-PCR analysis indicated that either HFD or leptin administration upregulated mRNA expression of several components of the RAS and PICs in the LT and PVN. The leptin antagonist and the inhibitors of AT1-R, TNF-α synthesis and microglial activation all reversed the expression of these genes. The results suggest that HFD-induced sensitization of Ang II-elicited hypertension is mediated by leptin through upregulation of central RAS and PICs. PMID:27021010

  20. Aging and human hormonal and pressor responsiveness to angiotensin II infusion with simultaneous measurement of exogenous and endogenous angiotensin II.

    Science.gov (United States)

    Duggan, J; Nussberger, J; Kilfeather, S; O'Malley, K

    1993-08-01

    A decline in the function of the renin angiotensin aldosterone system may induce adaptive changes in response to angiotensin II (ANG II) with age. We have examined platelet ANG II receptor density, blood pressure and aldosterone responses to ANG II [Asn1, Val5-ANG II] (Hypertensin, Ciba Geigy, Horsham, Sussex, England) infusion in 8 young, 24 to 30 years, and 8 older, 54 to 65 years, healthy volunteers. To measure circulating ANG II, we established a new method for specific and simultaneous measurement of exogenous [Asn1, Val5] (Hypertensin) and endogenous [Asp1,Ile5] ANG II in plasma by using isocratic HPLC and radioimmunoassays with cross-reacting antibodies and compared results with immunoreactive ANG II which was measured conventionally using monoclonal antibodies. Baseline endogenous ANG II (Asp1,Ile5-ANG II) levels in venous plasma were marginally, but not significantly, lower in the old [mean (95% confidence limits): 3.4 (Hypertensin infusion appeared consistently, but not significantly, lower in the old [0.9 (0 to 3.1) v 2.1 (0.6 to 3.7), after 3 ng/kg/min], while the same infusion rate in young and old resulted in similar plasma Hypertensin levels. Baseline systolic blood pressure (SBP) was similar in both groups but the percentage increases in SBP at infusion rates of 1, 3.0, and 10 ng/kg/min were greater in the old than in the young (9.1 v 2.8, P < .05; 16.3 v 8.0, P < .01; 30.4 v 14.0%, P < .001, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Plasma renin activity, aldosterone and dopamine beta-hydroxylase activity as a function of age in normal children.

    Science.gov (United States)

    Vincent, M; Dessart, Y; Annat, G; Sassard, J; Francois, R; Cier, J F

    1980-07-01

    In 149 children between 6 days and 15 years of age, plasma renin activity (PRA) and aldosterone (PA) were measured by radioimmunoassay and plasma dopamine beta hydroxylase activity (DBH) by the method of Nagatsu. PRA and PA decreased with age from 496 +/- 119 ng/1/min for PRA and 643 +/- 158 pg/ml for PA in 6 to 30 day-old newborns to 37.8 +/- 4.7 ng/1/min for PRA and 43. 1+/- 8.3 ph/ml for PA in 9 to 15 year-old children. DBH increased with age from less than detection limit values (< 2 IU) in 6 day to 3 month-old newborns to 17.2 +/- 5.1 IU in 9 to 15 year-old children. In addition a significant relationship was found between PRA and PA (log PA = 0.99 log PRA -0.058, r = 0.732, n = 104, p < 0.001) and PRA and DBH (log DBH = -0.41 log PRA +1.62, r = 0.404, n = 80, p < 0.001). These results demonstrate the opposite evolution of the Renin-Angiotensin-Aldosterone System and of the sympathoadrenal system during development.

  2. Distal renal tubules are deficient in aggresome formation and autophagy upon aldosterone administration.

    Science.gov (United States)

    Cheema, Muhammad Umar; Damkier, Helle Hasager; Nielsen, Jakob; Poulsen, Ebbe Toftgaard; Enghild, Jan J; Fenton, Robert A; Praetorius, Jeppe

    2014-01-01

    Prolonged elevations of plasma aldosterone levels are associated with renal pathogenesis. We hypothesized that renal distress could be imposed by an augmented aldosterone-induced protein turnover challenging cellular protein degradation systems of the renal tubular cells. Cellular accumulation of specific protein aggregates in rat kidneys was assessed after 7 days of aldosterone administration. Aldosterone induced intracellular accumulation of 60 s ribosomal protein L22 in protein aggregates, specifically in the distal convoluted tubules. The mineralocorticoid receptor inhibitor spironolactone abolished aldosterone-induced accumulation of these aggregates. The aldosterone-induced protein aggregates also contained proteasome 20 s subunits. The partial de-ubiquitinase ataxin-3 was not localized to the distal renal tubule protein aggregates, and the aggregates only modestly colocalized with aggresome transfer proteins dynactin p62 and histone deacetylase 6. Intracellular protein aggregation in distal renal tubules did not lead to development of classical juxta-nuclear aggresomes or to autophagosome formation. Finally, aldosterone treatment induced foci in renal cortex of epithelial vimentin expression and a loss of E-cadherin expression, as signs of cellular stress. The cellular changes occurred within high, but physiological aldosterone concentrations. We conclude that aldosterone induces protein accumulation in distal renal tubules; these aggregates are not cleared by autophagy that may lead to early renal tubular damage.

  3. Distal renal tubules are deficient in aggresome formation and autophagy upon aldosterone administration.

    Directory of Open Access Journals (Sweden)

    Muhammad Umar Cheema

    Full Text Available Prolonged elevations of plasma aldosterone levels are associated with renal pathogenesis. We hypothesized that renal distress could be imposed by an augmented aldosterone-induced protein turnover challenging cellular protein degradation systems of the renal tubular cells. Cellular accumulation of specific protein aggregates in rat kidneys was assessed after 7 days of aldosterone administration. Aldosterone induced intracellular accumulation of 60 s ribosomal protein L22 in protein aggregates, specifically in the distal convoluted tubules. The mineralocorticoid receptor inhibitor spironolactone abolished aldosterone-induced accumulation of these aggregates. The aldosterone-induced protein aggregates also contained proteasome 20 s subunits. The partial de-ubiquitinase ataxin-3 was not localized to the distal renal tubule protein aggregates, and the aggregates only modestly colocalized with aggresome transfer proteins dynactin p62 and histone deacetylase 6. Intracellular protein aggregation in distal renal tubules did not lead to development of classical juxta-nuclear aggresomes or to autophagosome formation. Finally, aldosterone treatment induced foci in renal cortex of epithelial vimentin expression and a loss of E-cadherin expression, as signs of cellular stress. The cellular changes occurred within high, but physiological aldosterone concentrations. We conclude that aldosterone induces protein accumulation in distal renal tubules; these aggregates are not cleared by autophagy that may lead to early renal tubular damage.

  4. Structural characteristics and antihypertensive effects of angiotensin ...

    African Journals Online (AJOL)

    Structural characteristics and antihypertensive effects of angiotensin-iconverting enzyme inhibitory peptides in the renin-angiotensin and kallikrein kinin systems. ... Background: The commercially available synthetic angiotensin-I-converting enzyme (ACE) inhibitors are known to exert negative side effects which have driven ...

  5. Importance of the Brain Angiotensin System in Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    John W. Wright

    2012-01-01

    Full Text Available Parkinson’s disease (PD has become a major health problem affecting 1.5% of the world’s population over 65 years of age. As life expectancy has increased so has the occurrence of PD. The primary direct consequence of this disease is the loss of dopaminergic (DA neurons in the substantia nigra and striatum. As the intensity of motor dysfunction increases, the symptomatic triad of bradykinesia, tremors-at-rest, and rigidity occur. Progressive neurodegeneration may also impact non-DA neurotransmitter systems including cholinergic, noradrenergic, and serotonergic, often leading to the development of depression, sleep disturbances, dementia, and autonomic nervous system failure. L-DOPA is the most efficacious oral delivery treatment for controlling motor symptoms; however, this approach is ineffective regarding nonmotor symptoms. New treatment strategies are needed designed to provide neuroprotection and encourage neurogenesis and synaptogenesis to slow or reverse this disease process. The hepatocyte growth factor (HGF/c-Met receptor system is a member of the growth factor family and has been shown to protect against degeneration of DA neurons in animal models. Recently, small angiotensin-based blood-brain barrier penetrant mimetics have been developed that activate this HGF/c-Met system. These compounds may offer a new and novel approach to the treatment of Parkinson’s disease.

  6. An interaction of renin-angiotensin and kallikrein-kinin systems contributes to vascular hypertrophy in angiotensin II-induced hypertension: in vivo and in vitro studies.

    Directory of Open Access Journals (Sweden)

    Graziela S Ceravolo

    Full Text Available The kallikrein-kinin and renin-angiotensin systems interact at multiple levels. In the present study, we tested the hypothesis that the B1 kinin receptor (B1R contributes to vascular hypertrophy in angiotensin II (ANG II-induced hypertension, through a mechanism involving reactive oxygen species (ROS generation and extracellular signal-regulated kinase (ERK1/2 activation. Male Wistar rats were infused with vehicle (control rats, 400 ng/Kg/min ANG II (ANG II rats or 400 ng/Kg/min ANG II plus B1 receptor antagonist, 350 ng/Kg/min des-Arg(9-Leu(8-bradykinin (ANGII+DAL rats, via osmotic mini-pumps (14 days or received ANG II plus losartan (10 mg/Kg, 14 days, gavage - ANG II+LOS rats. After 14 days, ANG II rats exhibited increased systolic arterial pressure [(mmHg 184 ± 5.9 vs 115 ± 2.3], aortic hypertrophy; increased ROS generation [2-hydroxyethidium/dihydroethidium (EOH/DHE: 21.8 ± 2.7 vs 6.0 ± 1.8] and ERK1/2 phosphorylation (% of control: 218.3 ± 29.4 vs 100 ± 0.25]. B1R expression was increased in aortas from ANG II and ANG II+DAL rats than in aortas from the ANG II+LOS and control groups. B1R antagonism reduced aorta hypertrophy, prevented ROS generation (EOH/DHE: 9.17 ± 3.1 and ERK1/2 phosphorylation (137 ± 20.7% in ANG II rats. Cultured aortic vascular smooth muscle cells (VSMC stimulated with low concentrations (0.1 nM of ANG II plus B1R agonist exhibited increased ROS generation, ERK1/2 phosphorylation, proliferating-cell nuclear antigen expression and [H3]leucine incorporation. At this concentration, neither ANG II nor the B1R agonist produced any effects when tested individually. The ANG II/B1R agonist synergism was inhibited by losartan (AT1 blocker, 10 µM, B1R antagonist (10 µM and Tiron (superoxide anion scavenger, 10 mM. These data suggest that B1R activation contributes to ANG II-induced aortic hypertrophy. This is associated with activation of redox-regulated ERK1/2 pathway that controls aortic smooth muscle cells growth

  7. Prevention of microalbuminuria using early intervention with renin-angiotensin system inhibitors in patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Persson, Frederik; Lindhardt, Morten; Rossing, Peter

    2016-01-01

    Hypothesis/objectives: Early prevention of diabetic nephropathy by way of blocking the renin-angiotensin system (RAS) in patients with normoalbuminuria seems rational, but trials have so far shown conflicting results. The present meta-analysis was undertaken to investigate if such treatment can p......-cause mortality(p=0.07). Conclusions: We conclude that in patients with type 2 diabetes and normoalbuminuria, early intervention with ACEis or ARBs reduces the risk for development of microalbuminuria.......Hypothesis/objectives: Early prevention of diabetic nephropathy by way of blocking the renin-angiotensin system (RAS) in patients with normoalbuminuria seems rational, but trials have so far shown conflicting results. The present meta-analysis was undertaken to investigate if such treatment can...

  8. The PGE(2)-EP4 receptor is necessary for stimulation of the renin-angiotensin-aldosterone system in response to low dietary salt intake in vivo

    DEFF Research Database (Denmark)

    Pöschke, Antje; Kern, Niklas; Maruyama, Takayuki

    2012-01-01

    a similar attenuation of Na(+) excretion; however, diuresis and K(+) excretion were enhanced, and plasma Na(+) concentration was higher, whereas plasma K(+) concentration was lower compared with control diet. There were no significant differences between EP4(+/+) and EP4(-/-) mice in blood pressure......Increased cyclooxygenase-2 (COX-2) expression and PGE(2) synthesis have been shown to be prerequisites for renal renin release after Na(+) deprivation. To answer the question of whether EP4 receptor type of PGE(2) mediates renin regulation under a low-salt diet, we examined renin regulation in EP4......(+/+), EP4(-/-), and in wild-type mice treated with EP4 receptor antagonist. After 2 wk of a low-salt diet (0.02% wt/wt NaCl), EP4(+/+) mice showed diminished Na(+) excretion, unchanged K(+) excretion, and reduced Ca(2+) excretion. Diuresis and plasma electrolytes remained unchanged. EP4(-/-) exhibited...

  9. Long-Term Regulation of the Local Renin-Angiotensin System in the Myocardium of Spontaneously Hypertensive Rats by Feeding Bioactive Peptides Derived from Spirulina platensis.

    Science.gov (United States)

    Pan, Huanglei; She, Xingxing; Wu, Hongli; Ma, Jun; Ren, Difeng; Lu, Jun

    2015-09-09

    This study investigated the long-term (8 weeks) anti-hypertensive effects of 10 mg/kg tripeptides isolated from Spirulina platensis, Ile-Gln-Pro (IQP) and Val-Glu-Pro (VEP), and S. platensis hydrolysates (SH) on spontaneously hypertensive rats. The treatment period was 6 weeks, and observation continued for another 2 weeks. After treatment, weighted systolic blood pressure, weighted diastolic blood pressure, left ventricular mass index, and right ventricular mass index of groups treated with IQP, VEP, and SH were significantly lower than those of the group treated with distilled water, even when the treatments had been withdrawn for 2 weeks. Quantitative real-time polymerase chain reaction, enzyme-linked immunosorbent assay, and Western blotting showed the mRNA expression levels and protein/peptide concentrations of the main components of the renin angiotensin system in myocardium were significantly affected by treatment: angiotensin converting enzyme, angiotensin II, and angiotensin type 1 receptor were down-regulated, whereas angiotensin type 2 receptor, angiotensin converting enzyme 2, angiotensin-(1-7), and Mas receptor were up-regulated.

  10. Impact of The Protective Renin-Angiotensin System (RAS) on The Vasoreparative Function of CD34+ CACs in Diabetic Retinopathy

    Science.gov (United States)

    Duan, Yaqian; Moldovan, Leni; Miller, Rehae C.; Beli, Eleni; Salazar, Tatiana; Hazra, Sugata; Al-Sabah, Jude; Chalam, KV; Raghunandan, Sneha; Vyas, Ruchi; hide

    2016-01-01

    Purpose: In diabetes, the impaired vasoreparative function of Circulating Angiogenic Cells (CACs) is believed to contribute to the progression of diabetic retinopathy (DR). Accumulating evidence suggests that the protective arm of renin-angiotensin system (RAS) ACE2 Angiotensin-(1-7) Mas plays an important role in restoring the function of diabetic CACs. We examined the protective RAS in CACs in diabetic individuals with different stages of retinopathy. Methods: Study subjects (n43) were recruited as controls or diabetics with either no DR, mild non-proliferative DR (NPDR), moderate NPDR, severe NPDR or proliferative DR (PDR). Fundus photography and fluorescein angiograms were analyzed using Vessel Generation Analysis (VESGEN) software in a cohort of subjects. CD34+ CACs were isolated from peripheral blood of diabetics and control subjects. RAS gene expressions in CACs were measured by qPCR. The vasoreparative function of CACs was assessed by migration ability toward CXCL12 using the QCM 5M 96-well chemotaxis cell migration assay. Results: ACE2 gene is a key enzyme converting the deleterious Angiotensin II to the beneficial Angiotensin-(1-7). ACE2 expression in CACs from diabetic subjects without DR was increased compared to controls, suggestive of compensation (p0.0437). The expression of Mas (Angiotensin-(1-7) receptor) in CACs was also increased in diabetics without DR, while was reduced in NPDR compared to controls (p0.0002), indicating a possible loss of compensation of the protective RAS at this stage of DR. The presence of even mild NPDR was associated with CD34+ CAC migratory dysfunction. When pretreating CACs of DR subjects with Angiotensin-(1-7), migratory ability to a chemoattractant CXCL12 was restored (p0.0008). By VESGEN analysis, an increase in small vessel density was observed in NPDR subjects when compared with the controls. Conclusions: These data suggest the protective RAS axis within diabetic CACs may help maintain their vasoreparative potential

  11. Role of Renin-Angiotensin System and Oxidative Stress on Vascular Inflammation in Insulin Resistence Model

    Directory of Open Access Journals (Sweden)

    N. F. Renna

    2013-01-01

    Full Text Available (1 This study aims to demonstrate the causal involvement of renin angiotensin system (RAS and oxidative stress (OS on vascular inflammation in an experimental model of metabolic syndrome (MS achieved by fructose administration to spontaneously hypertensive rats (FFHR during 12 weeks. (2 Chronic treatment with candesartan (C (10 mg/kg per day for the last 6 weeks or 4OH-Tempol (T (10−3 mmol/L in drinking water for the last 6 weeks reversed the increment in metabolic variables and systolic blood pressure. In addition, chronic C treatment reverted cardiovascular remodeling but not T. (3 Furthermore, chronic treatment with C was able to completely reverse the expression of NF-κB and VCAM-1, but T only reduced the expression. C reduced the expression of proatherogenic cytokines as CINC2, CINC3, VEGF, Leptin, TNF-alpha, and MCP-1 and also significantly reduced MIP-3, beta-NGF, and INF-gamma in vascular tissue in this experimental model. T was not able to substantially modify the expression of these cytokines. (4 The data suggest the involvement of RAS in the expression of inflammatory proteins at different vascular levels, allowing the creation of a microenvironment suitable for the creation, perpetuation, growth, and destabilization of vascular injury.

  12. Persistent phenotypic shift in cardiac fibroblasts: impact of transient renin angiotensin system inhibition.

    Science.gov (United States)

    Hale, Taben M

    2016-04-01

    Fibrotic cardiac remodeling ultimately leads to heart failure - a debilitating and costly condition. Select antihypertensive agents have been effective in reducing or slowing the development of cardiac fibrosis. Moreover, some experimental studies have shown that the reduction in fibrosis induced by these agents persists long after stopping treatment. What has not been as well investigated is whether this transient treatment results in a protection against future fibrotic cardiac remodeling. In the present review, previously published studies are re-examined to assess whether the relative percent increase in collagen deposition over an off-treatment period is attenuated, relative to control, following transient antihypertensive treatment in young or adult rats. Present findings suggest that transient inhibition of the renin angiotensin system (RAS) not only produces a sustained reduction in cardiac fibrosis, but also results in a degree of protection against future collagen deposition. In addition, prior transient RAS inhibition appears to alter the cardiac fibroblast phenotype such that these cells show a muted response to myocardial injury - namely reduced proliferation, chemokine release, and collagen deposition. This review puts forth several potential mechanisms underlying this long-term cardiac protection that is afforded by transient RAS inhibition. Specifically, fibroblast phenotypic change, cardiac fibroblast apoptosis, sustained suppression of the RAS, persistent reduction in left ventricular hypertrophy, and persistent reduction in arterial pressure are each discussed. Identifying the mechanisms ultimately responsible for this change in cardiac fibroblast response to injury, hypertension, and aging may reveal novel targets for therapy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Renin-Angiotensin System Genes Polymorphisms and Essential Hypertension in Burkina Faso, West Africa

    Directory of Open Access Journals (Sweden)

    Daméhan Tchelougou

    2015-01-01

    Full Text Available Objective. This study aimed to investigate the association between three polymorphisms of renin-angiotensin system and the essential hypertension in the population of Burkina Faso. Methodology. This was a case-control study including 202 cases and 204 matched controls subjects. The polymorphisms were identified by a classical and a real-time PCR. Results. The AGT 235M/T and AT1R 1166A/C polymorphisms were not associated with the hypertension while the genotype frequencies of the ACE I/D polymorphism between patients and controls (DD: 66.83% and 35.78%, ID: 28.22% and 50.98%, II: 4.95% and 13.24%, resp. were significantly different (p < 10−4. The genotype DD of ACE gene (OR = 3.40, p < 0.0001, the increasing age (OR = 3.83, p < 0.0001, obesity (OR = 4.84, p < 0.0001, dyslipidemia (OR = 3.43, p = 0.021, and alcohol intake (OR = 2.76, p < 0.0001 were identified as the independent risk factors for hypertension by multinomial logistic regression. Conclusion. The DD genotype of the ACE gene is involved in susceptibility to hypertension. Further investigations are needed to better monitor and provide individualized care for hypertensive patients.

  14. Inhibition of reactive oxygen species in hypothalamic paraventricular nucleus attenuates the renin–angiotensin system and proinflammatory cytokines in hypertension

    International Nuclear Information System (INIS)

    Su, Qing; Qin, Da-Nian; Wang, Fu-Xin; Ren, Jun; Li, Hong-Bao; Zhang, Meng; Yang, Qing; Miao, Yu-Wang; Yu, Xiao-Jing; Qi, Jie; Zhu, Zhiming; Zhu, Guo-Qing; Kang, Yu-Ming

    2014-01-01

    Aims: To explore whether reactive oxygen species (ROS) scavenger (tempol) in the hypothalamic paraventricular nucleus (PVN) attenuates renin–angiotensin system (RAS) and proinflammatory cytokines (PICs), and decreases the blood pressure and sympathetic activity in angiotensin II (ANG II)-induced hypertension. Methods and results: Male Sprague–Dawley rats were infused intravenously with ANG II (10 ng/kg per min) or normal saline (NS) for 4 weeks. These rats were treated with bilateral PVN infusion of oxygen free radical scavenger tempol (TEMP, 20 μg/h) or vehicle (artificial cerebrospinal fluid, aCSF) for 4 weeks. ANG II infusion resulted in increased mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA). These ANG II-infused rats also had higher levels of gp91 phox (a subunit of NAD(P)H oxidase), angiotensin-converting enzyme (ACE), and interleukin-1beta (IL-1β) in the PVN than the control animals. Treatment with PVN infusion of TEMP attenuated the overexpression of gp91 phox , ACE and IL-1β within the PVN, and decreased sympathetic activity and MAP in ANG II-infused rats. Conclusion: These findings suggest that ANG II infusion induces elevated PICs and oxidative stress in the PVN, which contribute to the sympathoexcitation in hypertension. Inhibition of reactive oxygen species in hypothalamic paraventricular nucleus attenuates the renin–angiotensin system, proinflammatory cytokines and oxidative stress in ANG II-induced hypertension. - Highlights: • The effect of chronic inhibiting PVN superoxide on hypertension was investigated. • ANG II infusion induced increased proinflammatory cytokines and superoxide in PVN. • ANG II infusion resulted in oxidative stress, sympathoexcitation and hypertension. • Chronic inhibiting PVN superoxide attenuates RAS and cytokines in hypertension

  15. Inhibition of reactive oxygen species in hypothalamic paraventricular nucleus attenuates the renin–angiotensin system and proinflammatory cytokines in hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Su, Qing [Department of Physiology and Pathophysiology, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University School of Medicine, Xi' an 710061 (China); Qin, Da-Nian, E-mail: dnqin@stu.edu.cn [Department of Physiology, Shantou University Medical College, Shantou 515041 (China); Wang, Fu-Xin [Department of Neurology, The First Affiliated Hospital of Jiamusi University, Jiamusi 154002 (China); Ren, Jun [Center for Cardiovascular Research and Alternative Medicine, University of Wyoming, Laramie, WY 82071 (United States); Li, Hong-Bao; Zhang, Meng; Yang, Qing; Miao, Yu-Wang; Yu, Xiao-Jing; Qi, Jie [Department of Physiology and Pathophysiology, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University School of Medicine, Xi' an 710061 (China); Zhu, Zhiming [Department of Hypertension and Endocrinology, Center for Hypertension and Metabolic Diseases, Daping Hospital, The Third Military Medical University, Chongqing Institute of Hypertension, Chongqing 400042 (China); Zhu, Guo-Qing [Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing 210029 (China); Kang, Yu-Ming, E-mail: ykang@mail.xjtu.edu.cn [Department of Physiology and Pathophysiology, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University School of Medicine, Xi' an 710061 (China)

    2014-04-15

    Aims: To explore whether reactive oxygen species (ROS) scavenger (tempol) in the hypothalamic paraventricular nucleus (PVN) attenuates renin–angiotensin system (RAS) and proinflammatory cytokines (PICs), and decreases the blood pressure and sympathetic activity in angiotensin II (ANG II)-induced hypertension. Methods and results: Male Sprague–Dawley rats were infused intravenously with ANG II (10 ng/kg per min) or normal saline (NS) for 4 weeks. These rats were treated with bilateral PVN infusion of oxygen free radical scavenger tempol (TEMP, 20 μg/h) or vehicle (artificial cerebrospinal fluid, aCSF) for 4 weeks. ANG II infusion resulted in increased mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA). These ANG II-infused rats also had higher levels of gp91{sup phox} (a subunit of NAD(P)H oxidase), angiotensin-converting enzyme (ACE), and interleukin-1beta (IL-1β) in the PVN than the control animals. Treatment with PVN infusion of TEMP attenuated the overexpression of gp91{sup phox}, ACE and IL-1β within the PVN, and decreased sympathetic activity and MAP in ANG II-infused rats. Conclusion: These findings suggest that ANG II infusion induces elevated PICs and oxidative stress in the PVN, which contribute to the sympathoexcitation in hypertension. Inhibition of reactive oxygen species in hypothalamic paraventricular nucleus attenuates the renin–angiotensin system, proinflammatory cytokines and oxidative stress in ANG II-induced hypertension. - Highlights: • The effect of chronic inhibiting PVN superoxide on hypertension was investigated. • ANG II infusion induced increased proinflammatory cytokines and superoxide in PVN. • ANG II infusion resulted in oxidative stress, sympathoexcitation and hypertension. • Chronic inhibiting PVN superoxide attenuates RAS and cytokines in hypertension.

  16. HEMODYNAMIC AND STRUCTURAL MODIFICATIONS IN CONTINUOUS INFUSION WITH ANGIOTENSIN. II. AN EXPERIMENTAL STUDY

    Directory of Open Access Journals (Sweden)

    Minela Aida Maranduca

    2011-09-01

    Full Text Available The renin-angiotensin-aldosterone system (RAAS is a hormonal system which contributes to the regulation of both arterial pressure and extra cellular fluids volume. The increase of RAAS, especially at angiotensin II (Ang II level, affects the target organs and increases the risk of cardio-vascular issues, by increasing arterial pressure and through the direct effect of Ang II upon the vascular endothelium and the renal and cardiac tissue. Ang II reduces the renal capacity of sodium excretion and initiates a set of events which increase arterial pressure. Increase of arterial pressure is necessary for re-establishing sodium excretion, being realized by the pressure-natriuresis relationship. Arterial hypertension affects the target organs (heart, kidneys and leads to a vicious circle which contributes to maintaining a high arterial pressure. Materials and Method: Male Wistar rats subjected on a normal diet, received either a sham operation (n=9 or continuous angiotensin II (Ang II infusion (300ng/kgc/ min subcutaneously, via mini pumps. Water ingestion and systolic blood pressure were measured for 14 days, after which the animals were sacrificed under anesthesia with ketamin, and the xylasin body weight, water ingestion, heart mass, right and left ventricular mass, right and left kidney mass were measured. Results: After 14 days of Ang II infusion, bodily weight decreased, systolic blood pressure increased, heart and left ventricular mass indexed to body weight were significantly enhanced compared with the sham group, and kidneys mass indexed to body weight was similar in the two groups.

  17. Influence of the renin-angiotensin system on human forearm blood flow

    DEFF Research Database (Denmark)

    Stadeager, C; Hesse, B; Henriksen, O

    1990-01-01

    Although angiotensin II is a potent vasoconstrictor agent in all tissues, including the human forearm, equivocal effects on forearm blood flow (FBF) have been found after angiotensin blockade. In 13 healthy Na(+)-depleted subjects FBF was measured by the 133Xe washout technique; subcutaneous...... and muscle blood flows were determined separately. FBF was measured during supine rest, after the arm was lowered, and during lower body negative pressure (LBNP). The measurements were repeated during intra-arterial saralasin infusion in six subjects and after intravenous administration of enalapril in seven....... It is concluded that, in the human forearm, angiotensin II is not necessary for sympathetic vasoconstrictor reflexes but may, through a central effect, have some influence on arteriolar tone at rest....

  18. Angiotensin type 2 receptors

    DEFF Research Database (Denmark)

    Sumners, Colin; de Kloet, Annette D; Krause, Eric G

    2015-01-01

    In most situations, the angiotensin AT2-receptor (AT2R) mediates physiological actions opposing those mediated by the AT1-receptor (AT1R), including a vasorelaxant effect. Nevertheless, experimental evidence vastly supports that systemic application of AT2R-agonists is blood pressure neutral...

  19. Cancer Stem Cells in Moderately Differentiated Buccal Mucosal Squamous Cell Carcinoma Express Components of the Renin-Angiotensin System

    Directory of Open Access Journals (Sweden)

    Therese Featherston

    2016-09-01

    Full Text Available Aim We have recently identified and characterized cancer stem cell (CSC subpopulations within moderately differentiated buccal mucosal squamous cell carcinoma (MDBMSCC. We hypothesized that these CSCs express components of the renin-angiotensin system (RAS.Methods 3,3-Diaminobenzidine (DAB immunohistochemical (IHC staining was performed on formalin-fixed paraffin-embedded MDBMSCC samples to investigate the expression of the components of the RAS: pro(renin receptor (PRR, angiotensin converting enzyme (ACE, angiotensin II receptor 1 (ATIIR1 and angiotensin II receptor 2 (ATIIR2. NanoString mRNA gene expression analysis and Western Blotting (WB were performed on snap-frozen MDBMSCC samples to confirm gene expression and translation of these transcripts, respectively. Double immunofluorescent (IF IHC staining of these components of the RAS with the embryonic stem cell markers OCT4 or SALL4 was performed to demonstrate their localization in relation to the CSC subpopulations within MDBMSCC.Results DAB IHC staining demonstrated expression of PRR, ACE, ATIIR1 and ATIIR2 in MDBMSCC. IF IHC staining showed that PRR was expressed by the CSC subpopulations within the tumor nests, the peri-tumoral stroma and the endothelium of the microvessels within the peri-tumoral stroma. ATIIR1 and ATIIR2 were localized to the CSC subpopulations within the tumor nests and the peri-tumoral stroma, while ACE was localized to the endothelium of the microvessels within the peri-tumoral stroma. WB and NanoString analyses confirmed protein expression and transcription activation of PRR, ACE and ATIIR1 but not of ATIIR2, respectively.

  20. Daily sesame oil supplementation attenuates local renin-angiotensin system via inhibiting MAPK activation and oxidative stress in cardiac hypertrophy.

    Science.gov (United States)

    Liu, Chuan-Teng; Liu, Ming-Yie

    2017-04-01

    The renin-angiotensin system (RAS) is involved in the development of left ventricular hypertrophy (LVH) by which increases cardiac morbidity and mortality. Activation of mitogen-activated protein kinases (MAPKs) and oxidative stress are important in RAS-mediated cardiac hypertrophy. Sesame oil, a potent antioxidant, attenuates hypertension-dependent LVH. We examined the protective role of sesame oil on RAS-mediated MAPK activation and oxidative stress in rats. We induced LVH using a hypertensive model by subcutaneously injecting deoxycorticosterone acetate (DOCA; 15 mg/ml/kg in mineral oil; twice weekly for 5 weeks) and supplementing with 1% sodium chloride drinking water (DOCA/salt) to uninephrectomized rats. Sesame oil was gavaged (0.5 or 1 ml/kg/day for 7 days) after 4 weeks of DOCA/salt treatment. Cardiac histopathology, RAS parameters, expression of MAPKs, reactive oxygen species and lipid peroxidation were assessed 24 h after the last dose of sesame oil. Sesame oil significantly decreased the size of cardiomyocytes and the levels of cardiac renin, angiotensin-converting enzyme and angiotensin II. In addition, sesame oil down-regulated the expression of angiotensin type 1 receptor, JNK and p38 MAPK and apoptosis signal regulating kinase 1, c-Fos and c-Jun in rats receiving DOCA/salt. Furthermore, the induction of nicotinamide adenine dinucleotide phosphate oxidase, superoxide anion and hydroxyl radical and lipid peroxidation by DOCA/salt were inhibited by sesame oil. Sesame oil modulates cardiac RAS to ameliorate LVH by inhibiting MAPK activation and lowering oxidative stress. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Angioedema Triggered by Medication Blocking the Renin/Angiotensin System: Retrospective Study Using the French National Pharmacovigilance Database.

    Science.gov (United States)

    Faisant, Charles; Armengol, Guillaume; Bouillet, Laurence; Boccon-Gibod, Isabelle; Villier, Céline; Lévesque, Hervé; Cottin, Judith; Massy, Nathalie; Benhamou, Ygal

    2016-01-01

    Bradykinin-mediated angioedema (AE) is a rare side effect of some medications, including angiotensin converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARB). In France, side-effects to treatments are reported to the national pharmacovigilance database. The national MedDRA database was searched using the term "angioedema". Patients were included if they met the clinical criteria corresponding to bradykinin-mediated AE, if their C1-inhibitor levels were normal, and if they were treated with an ACEi or an ARB. 7998 cases of AE were reported between 1994 and 2013. Among these, 112 met the criteria for bradykinin-mediated AE with normal C1-inhibitor levels. On the 112 drug-AE, patients were treated with an ARB in 21% of cases (24 patients), or an ACEi in 77% of cases (88 patients), in combination with another treatment in 17 cases (mTORi for 3 patients, iDPP-4 for 1 patient, hormonal treatment for 7 patients). ENT involvement was reported in 90% of cases (tongue: 48.2%, larynx: 23.2%). The median duration of treatment before the first attack was 720 days, and the mean duration of attacks was 36.6 h. Forty-one percent (19/46) of patients relapsed after discontinuing treatment. Angioedema triggered by medication blocking the renin/angiotensin system is rare but potentially severe, with a high risk of recurrence despite cessation of the causative drug.

  2. Renin-angiotensin system-related highlights from the High Blood Pressure Research Conference annual meeting.

    Science.gov (United States)

    Luft, Friedrich C

    2008-12-01

    The High Blood Pressure Research Conference of the American Heart Association is a theoretical meeting for hypertension researchers who direct their attention to hypertension-related basic disease mechanisms. The items that I have selected for this brief review are molecular intracellular receptor function, novel angiotensin (Ang)-related pathways, including Ang-(1-7), the Mas receptor, and angiotensin-converting enzyme 2, oxidative stress, immunity, the (pro)renin receptor, and until now unappreciated signalling pathways, such as the tonicity element binding protein.

  3. Non-genomic actions of aldosterone: From receptors and signals to membrane targets.

    LENUS (Irish Health Repository)

    2012-02-01

    In tissues which express the mineralocorticoid receptor (MR), aldosterone modulates the expression of membrane targets such as the subunits of the epithelial Na(+) channel, in combination with important signalling intermediates such as serum and glucocorticoid-regulated kinase-1. In addition, the rapid \\'non-genomic\\' activation of protein kinases and secondary messenger signalling cascades has also been detected in aldosterone-sensitive tissues of the nephron, distal colon and cardiovascular system. These rapid actions are variously described as being coupled to MR or to an as yet unidentified, membrane-associated aldosterone receptor. The rapidly activated signalling cascades add a level of fine-tuning to the activity of aldosterone-responsive membrane transporters and also modulate the aldosterone-induced changes in gene expression through receptor and transcription factor phosphorylation.

  4. Non-genomic actions of aldosterone: From receptors and signals to membrane targets.

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2011-07-26

    In tissues which express the mineralocorticoid receptor (MR), aldosterone modulates the expression of membrane targets such as the subunits of the epithelial Na(+) channel, in combination with important signalling intermediates such as serum and glucocorticoid-regulated kinase-1. In addition, the rapid \\'non-genomic\\' activation of protein kinases and secondary messenger signalling cascades has also been detected in aldosterone-sensitive tissues of the nephron, distal colon and cardiovascular system. These rapid actions are variously described as being coupled to MR or to an as yet unidentified, membrane-associated aldosterone receptor. The rapidly activated signalling cascades add a level of fine-tuning to the activity of aldosterone-responsive membrane transporters and also modulate the aldosterone-induced changes in gene expression through receptor and transcription factor phosphorylation.

  5. The effect of serum angiotensin II and angiotensin II type 1 receptor ...

    African Journals Online (AJOL)

    Ehab

    2012-06-18

    Jun 18, 2012 ... The effect of serum angiotensin II and angiotensin II type 1 receptor gene polymorphism on pediatric lupus nephritis. INTRODUCTION. Renin angiotensin system (RAS) has been considered one of the probable pathophysiologic mechanisms involved in SLE progression. However, the contribution of the ...

  6. Method for the optimum formation of angiotensin I from angiotensinogen and radioimmunoassay for angiotensin I

    International Nuclear Information System (INIS)

    Pagnucco, R.G.; Murty, D.R.; Muse, R.J.

    1978-01-01

    The invention deals with a method to optimize the formation of angiotensin I from angiotensinogens by optimizing the temperature, pH value and buffer system. Furthermore, the invention concerns a radioimmunoassay method to determine angiotensin I. Iodine 125 labelled angiotensin I is preferably used as tracer. (VJ) [de

  7. Angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers in patients with abdominal aortic aneurysms

    DEFF Research Database (Denmark)

    Kristensen, Karl Emil; Torp-Pedersen, Christian; Gislason, Gunnar Hilmar

    2015-01-01

    OBJECTIVE: The renin-angiotensin system is thought to play a pivotal role in the pathogenesis of abdominal aortic aneurysms (AAAs). However, effects of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II type 1 receptor blockers (ARBs) on human AAAs remain unclear. We therefore ex...

  8. Role of the renin-angiotensin system in regulation and autoregulation of renal blood flow

    DEFF Research Database (Denmark)

    Sørensen, Charlotte Mehlin; Leyssac, Paul Peter; Skøtt, Ole

    2000-01-01

    The role for ANG II in renal blood flow (RBF) autoregulation is unsettled. The present study was designed to test the effect of clamping plasma ANG II concentrations ([ANG II]) by simultaneous infusion of the angiotensin-converting enzyme inhibitor captopril and ANG II on RBF autoregulation...

  9. Discovery and Characterization of Alamandine, a Novel Component of the Renin-Angiotensin System

    DEFF Research Database (Denmark)

    Lautner, Roberto Q.; Villela, Daniel C; Fraga-Silva, Rodrigo A

    2013-01-01

    by angiotensin-(1-7), including vasodilation, anti-fibrosis, anti-hypertensive and central effects. Interestingly, our data reveals that its actions are independent of the known vasodilator receptors of the RAS, Mas and AT2. Rather, we demonstrate that alamandine acts through the Mas-related G-Protein coupled...

  10. Targeting the aldosterone pathway in cardiovascular disease

    DEFF Research Database (Denmark)

    Gustafsson, Finn; Azizi, Michel; Bauersachs, Johann

    2012-01-01

    Accumulated evidence has demonstrated that aldosterone is a key player in the pathogenesis of cardiovascular (CV) disease. Multiple clinical trials have documented that intervention in the aldosterone pathway can reduce blood pressure and lower albuminuria and improve outcome in patients with heart...... failure or myocardial infarction. Recent studies have unraveled details about the role of aldosterone at the cellular level in CV disease. The relative importance of glucocorticoids and aldosterone in terms of mineralocorticoid receptor activation is currently being debated. Also, studies are addressing...... which aldosterone modulator to use, which timing of treatment to aim for, and in which population to intervene. This review provides an overview of recent developments in the understanding of the role of aldosterone in CV disease, with particular reference to mechanisms and potential targets...

  11. Preoperative renin-angiotensin system inhibitors protect renal function in aging patients undergoing cardiac surgery.

    Science.gov (United States)

    Barodka, Viachaslau; Silvestry, Scott; Zhao, Ning; Jiao, Xiangyin; Whellan, David J; Diehl, James; Sun, Jian-Zhong

    2011-05-15

    Renal failure (RF) represents a major postoperative complication for elderly patients undergoing cardiac surgery. This observational cohort study examines effects of preoperative use of renin-angiotensin system (RAS) inhibitors on postoperative renal failure in aging patients undergoing cardiac surgery. We retrospectively analyzed a cohort of 1287 patients who underwent cardiac surgery at this institution (2003-2007). The patients included were ≥65 years old, scheduled for elective cardiac surgery, and without preexisting RF (defined by the criteria of the Society of Thoracic Surgeons as described in Method). Of all patients evaluated, 346 patients met the inclusion criteria and were divided into two groups: using (n = 122) or not using (n = 224) preoperative RAS inhibitors. A comparison of the two groups showed no significant differences in baseline parameters, including creatinine clearance, body mass index, history of diabetes and smoking, preoperative medicines (except that more patients with RAS inhibitors had a history of hypertension or congestive heart failure, fewer RAS inhibitor patients had chronic lung disease), in intraoperative perfusion and aortic cross-clamp time, and in postoperative complications and 30-d mortality. Multivariate logistic regression analysis demonstrated, however, that preoperative RAS inhibitors significantly and independently reduced the incidence of postoperative RF in the patients undergoing cardiac surgery compared with those not taking RAS inhibitors: 1.6% versus 7.6%, yielding an odds ratio of 0.19 (95 % CI 0.04-0.84, P = 0.029). Preoperative RAS inhibitors may have significant renoprotective effects for aging patients undergoing elective cardiac surgery. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Angiotensin II type 1 and 2 receptors and lymphatic vessels modulate lung remodeling and fibrosis in systemic sclerosis and idiopathic pulmonary fibrosis.

    Science.gov (United States)

    Parra, Edwin Roger; Ruppert, Aline Domingos Pinto; Capelozzi, Vera Luiza

    2014-01-01

    To validate the importance of the angiotensin II receptor isotypes and the lymphatic vessels in systemic sclerosis and idiopathic pulmonary fibrosis. We examined angiotensin II type 1 and 2 receptors and lymphatic vessels in the pulmonary tissues obtained from open lung biopsies of 30 patients with systemic sclerosis and 28 patients with idiopathic pulmonary fibrosis. Their histologic patterns included cellular and fibrotic non-specific interstitial pneumonia for systemic sclerosis and usual interstitial pneumonia for idiopathic pulmonary fibrosis. We used immunohistochemistry and histomorphometry to evaluate the number of cells in the alveolar septae and the vessels stained by these markers. Survival curves were also used. We found a significantly increased percentage of septal and vessel cells immunostained for the angiotensin type 1 and 2 receptors in the systemic sclerosis and idiopathic pulmonary fibrosis patients compared with the controls. A similar percentage of angiotensin 2 receptor positive vessel cells was observed in fibrotic non-specific interstitial pneumonia and usual interstitial pneumonia. A significantly increased percentage of lymphatic vessels was present in the usual interstitial pneumonia group compared with the non-specific interstitial pneumonia and control groups. A Cox regression analysis showed a high risk of death for the patients with usual interstitial pneumonia and a high percentage of vessel cells immunostained for the angiotensin 2 receptor in the lymphatic vessels. We concluded that angiotensin II receptor expression in the lung parenchyma can potentially control organ remodeling and fibrosis, which suggests that strategies aimed at preventing high angiotensin 2 receptor expression may be used as potential therapeutic target in patients with pulmonary systemic sclerosis and idiopathic pulmonary fibrosis.

  13. Interrelated aldosterone and parathyroid hormone mutually modify cardiovascular mortality risk

    NARCIS (Netherlands)

    Tomaschitz, Andreas; Pilz, Stefan; Rus-Machan, Jutta; Meinitzer, Andreas; Brandenburg, Vincent M; Scharnagl, Hubert; Kapl, Martin; Grammer, Tanja; Ritz, Eberhard; Horina, Jörg H; Kleber, Marcus E; Pieske, Burkert; Kraigher-Krainer, Elisabeth; Hartaigh, Bríain Ó; Toplak, Hermann; van Ballegooijen, Adriana J; Amrein, Karin; Fahrleitner-Pammer, Astrid; März, Winfried

    2015-01-01

    BACKGROUND: Inappropriate aldosterone and parathyroid hormone (PTH) secretion is associated with increased cardiovascular risk. Accumulating evidence suggests bidirectional interplay between aldosterone and PTH. METHODS: We evaluated the cross-sectional relationship between plasma aldosterone

  14. Serum creatinine elevation after renin-angiotensin system blockade and long term cardiorenal risks: cohort study.

    Science.gov (United States)

    Schmidt, Morten; Mansfield, Kathryn E; Bhaskaran, Krishnan; Nitsch, Dorothea; Sørensen, Henrik Toft; Smeeth, Liam; Tomlinson, Laurie A

    2017-03-09

    Objective  To examine long term cardiorenal outcomes associated with increased concentrations of creatinine after the start of angiotensin converting enzyme inhibitor/angiotensin receptor blocker treatment. Design  Population based cohort study using electronic health records from the Clinical Practice Research Datalink and Hospital Episode Statistics. Setting  UK primary care, 1997-2014. Participants  Patients starting treatment with angiotensin converting enzyme inhibitors or angiotensin receptor blockers (n=122 363). Main outcome measures  Poisson regression was used to compare rates of end stage renal disease, myocardial infarction, heart failure, and death among patients with creatinine increases of 30% or more after starting treatment against those without such increases, and for each 10% increase in creatinine. Analyses were adjusted for age, sex, calendar period, socioeconomic status, lifestyle factors, chronic kidney disease, diabetes, cardiovascular comorbidities, and use of other antihypertensive drugs and non-steroidal anti-inflammatory drugs. Results  Among the 2078 (1.7%) patients with creatinine increases of 30% or more, a higher proportion were female, were elderly, had cardiorenal comorbidity, and used non-steroidal anti-inflammatory drugs, loop diuretics, or potassium sparing diuretics. Creatinine increases of 30% or more were associated with an increased adjusted incidence rate ratio for all outcomes, compared with increases of less than 30%: 3.43 (95% confidence interval 2.40 to 4.91) for end stage renal disease, 1.46 (1.16 to 1.84) for myocardial infarction, 1.37 (1.14 to 1.65) for heart failure, and 1.84 (1.65 to 2.05) for death. The detailed categorisation of increases in creatinine concentrations (creatinine increases of less than 30% were also associated with increased incidence rate ratios for all outcomes, including death (1.15 (1.09 to 1.22) for increases of 10-19% and 1.35 (1.23 to 1.49) for increases of 20-29%, using creatinine

  15. Effects of acrolein on aldosterone release from zona glomerulosa cells in male rats.

    Science.gov (United States)

    Wang, Kai-Lee; Huang, Wen-Ching; Chou, Jou-Chun; Weng, Ting-Chun; Hu, Sindy; Lieu, Fu-Kong; Lai, Wei-Ho; Idova, Galina; Wang, Paulus S; Wang, Shyi-Wu

    2016-07-01

    A positive correlation between smoking and hypertension has been well established. Acrolein is a major toxic volatile compound found in cigarette smoke. Human exposure to low levels of acrolein is unavoidable due to its production in daily activities, such as smoke from industrial, hot oil cooking vapors, and exhaust fumes from vehicles. The toxicity and the action mechanism of acrolein to induce apoptosis have been extensively studied, but the effects of acrolein on hypertension are still unknown. The present study aimed to examine the effects of acrolein on aldosterone release both in vivo and in vitro. Male rats were divided into three groups, and intraperitoneally injected with normal saline, or acrolein (2mg/kg) for 1 (group A-1) or 3 (group A-3) days, respectively. After sacrificing, rat blood samples were obtained to measure plasma aldosterone and angiotensin II (Ang II) levels. Zona glomerulosa (ZG) cells were prepared from rat adrenal cortex, and were incubated with or without stimulants. We found that the serum aldosterone was increased by 1.2-fold (pacrolein enhanced the stimulatory effects of Ang II and 8-bromo-cyclic AMP on aldosterone secretion from ZG cells prepared in both A-1 and A-3 groups. Furthermore, the enzyme activity of P450scc, the rate-limiting step of aldosterone synthesis, was elevated after acrolein injection. Plasma level of Ang II was increased in both A-1 and A-3 groups. These results suggested that acrolein exposure increased aldosterone production, at least in part, through elevating the level of plasma Ang II and stimulating steroidogenesis pathways. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Rationale for an early aldosterone blockade in acute myocardial infarction and design of the ALBATROSS trial.

    Science.gov (United States)

    Beygui, Farzin; Vicaut, Eric; Ecollan, Patrick; Machecourt, Jacques; Van Belle, Eric; Zannad, Faiez; Montalescot, Gilles

    2010-10-01

    Aldosterone is at its highest levels at presentation for acute myocardial infarction (AMI). High aldosterone levels are predictive of poor outcome regardless of heart failure. Angiotensin-converting enzyme inhibitors have delayed partial and temporary effects on aldosterone levels. We hypothesize that aldosterone receptor blockade, early after AMI onset on top of standard therapy, may improve clinical outcome. ALBATROSS is a nationwide, multicenter, open-labeled, randomized trial designed to assess the superiority of aldosterone blockade by a 200-mg intravenous bolus of potassium canrenoate followed by a daily 25-mg dose of spirinolactone for 6 months, on top of standard therapy compared to standard therapy alone among 1,600 patients admitted for ST-segment elevation or high risk non-ST-segment elevation acute AMI -TIMI score ≥3-within 72 hours after symptom onset regardless of heart failure and treatment strategy. The primary efficacy end point of the study is the 6-month rate of the composite of death, resuscitated cardiac arrest, significant ventricular arrhythmia, class IA American College of Cardiology/American Heart Association/European Society of Cardiology indication for implantable cardioverter device, and new or worsening heart failure. Secondary end points include each of the components of the primary end point, different combinations of such components, the primary end point assessed at hospital discharge and 30-day follow-up, and rates of acute renal failure. Safety end points include rates of hyperkalemia and premature drug discontinuation. ALBATROSS will assess the cardiovascular benefit of a low-cost aldosterone receptor blocker on top of standard therapy in all-coming AMI patients. Copyright © 2010 Mosby, Inc. All rights reserved.

  17. Low birth weight activates the renin?angiotensin system, but limits cardiac angiogenesis in early postnatal life

    OpenAIRE

    Wang, Kimberley C W; Brooks, Doug A; Summers-Pearce, Brooke; Bobrovskaya, Larisa; Tosh, Darran N; Duffield, Jaime A; Botting, Kimberley J; Zhang, Song; Caroline McMillen, I; Morrison, Janna L

    2015-01-01

    Low birth weight (LBW) is associated with increased risk of adult cardiovascular disease and this association may be partly a consequence of early programming of the renin?angiotensin system (RAS). We investigated the effects of LBW on expression of molecules in the RAS and cardiac tissue remodeling. Left ventricular samples were collected from the hearts of 21?days old lambs that were born average birth weight (ABW) and LBW. Cardiac mRNA expression was quantified using real-time RT-PCR and p...

  18. Maternal Dexamethasone Treatment Alters Tissue and Circulating Components of the Renin-Angiotensin System in the Pregnant Ewe and Fetus

    Science.gov (United States)

    Jellyman, Juanita K.; De Blasio, Miles J.; Johnson, Emma; Giussani, Dino A.; Broughton Pipkin, Fiona; Fowden, Abigail L.

    2015-01-01

    Antenatal synthetic glucocorticoids promote fetal maturation in pregnant women at risk of preterm delivery and their mechanism of action may involve other endocrine systems. This study investigated the effect of maternal dexamethasone treatment, at clinically relevant doses, on components of the renin-angiotensin system (RAS) in the pregnant ewe and fetus. From 125 days of gestation (term, 145 ± 2 d), 10 ewes carrying single fetuses of mixed sex (3 female, 7 male) were injected twice im, at 10–11 pm, with dexamethasone (2 × 12 mg, n = 5) or saline (n = 5) at 24-hour intervals. At 10 hours after the second injection, maternal dexamethasone treatment increased angiotensin-converting enzyme (ACE) mRNA levels in the fetal lungs, kidneys, and heart and ACE concentration in the circulation and lungs, but not kidneys, of the fetuses. Fetal cardiac mRNA abundance of angiotensin II (AII) type 2 receptor decreased after maternal dexamethasone treatment. Between the two groups of fetuses, there were no significant differences in plasma angiotensinogen or renin concentrations; in transcript levels of renal renin, or AII type 1 or 2 receptors in the lungs and kidneys; or in pulmonary, renal or cardiac protein content of the AII receptors. In the pregnant ewes, dexamethasone administration increased pulmonary ACE and plasma angiotensinogen, and decreased plasma renin, concentrations. Some of the effects of dexamethasone treatment on the maternal and fetal RAS were associated with altered insulin and thyroid hormone activity. Changes in the local and circulating RAS induced by dexamethasone exposure in utero may contribute to the maturational and tissue-specific actions of antenatal glucocorticoid treatment. PMID:26039155

  19. Different expression of renin-angiotensin system components in hearts of normotensive and hypertensive rats

    Czech Academy of Sciences Publication Activity Database

    Jurkovičová, D.; Dobešová, Zdenka; Kuneš, Jaroslav; Križanová, O.

    2001-01-01

    Roč. 50, č. 1 (2001), s. 35-42 ISSN 0862-8408 R&D Projects: GA AV ČR IAA7011805 Grant - others:VEGA(SK) 2/7158(OK) Institutional research plan: CEZ:AV0Z5011922 Keywords : renin- angiotensin systém * heart * hypertension Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 1.027, year: 2001

  20. Circadian Differences in the Contribution of the Brain Renin-Angiotensin System in Genetically Hypertensive Mice

    Directory of Open Access Journals (Sweden)

    Kristy L. Jackson

    2018-03-01

    Full Text Available Objective: Genetically hypertensive BPH/2J mice are recognized as a neurogenic model of hypertension, primarily based on sympathetic overactivity and greater neuronal activity in cardiovascular regulatory brain regions. Greater activity of the central renin angiotensin system (RAS and reactive oxygen species (ROS reportedly contribute to other models of hypertension. Importantly the peripheral RAS contributes to the hypertension in BPH/2J mice, predominantly during the dark period of the 24 h light cycle. The aim of the present study was to determine whether central AT1 receptor stimulation and the associated ROS signaling contribute to hypertension in BPH/2J mice in a circadian dependent manner.Methods: Blood pressure (BP was measured in BPH/2J and normotensive BPN/3J mice (n = 7–8 via pre-implanted telemetry devices. Acute intracerebroventricular (ICV microinjections of AT1 receptor antagonist, candesartan, and the superoxide dismutase (SOD mimetic, tempol, were administered during the dark and light period of the 24 h light cycle via a pre-implanted ICV guide cannula. In separate mice, the BP effect of ICV infusion of the AT1 receptor antagonist losartan for 7 days was compared with subcutaneous infusion to determine the contribution of the central RAS to hypertension in BPH/2J mice.Results: Candesartan administered ICV during the dark period induced depressor responses which were 40% smaller in BPH/2J than BPN/3J mice (Pstrain < 0.05, suggesting AT1 receptor stimulation may contribute less to BP maintenance in BPH/2J mice. During the light period candesartan had minimal effect on BP in either strain. ICV tempol had comparable effects on BP between strains during the light and dark period (Pstrain > 0.08, suggesting ROS signaling is also not contributing to the hypertension in BPH/2J mice. Chronic ICV administration of losartan (22 nmol/h had minimal effect on BPN/3J mice. By contrast in BPH/2J mice, both ICV and subcutaneously administered

  1. Regulation of arterial reactivity by concurrent signaling through the E-prostanoid receptor 3 and angiotensin receptor 1.

    Science.gov (United States)

    Kraemer, Maria P; Choi, Hyehun; Reese, Jeff; Lamb, Fred S; Breyer, Richard M

    2016-09-01

    Prostaglandin E2 (PGE2), a cyclooxygenase metabolite that generally acts as a systemic vasodepressor, has been shown to have vasopressor effects under certain physiologic conditions. Previous studies have demonstrated that PGE2 receptor signaling modulates angiotensin II (Ang II)-induced hypertension, but the interaction of these two systems in the regulation of vascular reactivity is incompletely characterized. We hypothesized that Ang II, a principal effector of the renin-angiotensin-aldosterone system, potentiates PGE2-mediated vasoconstriction. Here we demonstrate that pre-treatment of arterial rings with 1nM Ang II potentiated PGE2-evoked constriction in a concentration dependent manner (AUC-Ang II 2.778±2.091, AUC+Ang II 22.830±8.560, ***Pantagonists, we demonstrate that this potentiation effect is mediated via concurrent signaling between the angiotensin II receptor 1 (AT1) and the PGE2 E-prostanoid receptor 3 (EP3) in the mouse femoral artery. EP3 receptor-mediated vasoconstriction is shown to be dependent on extracellular calcium in combination with proline-rich tyrosine kinase 2 (Pyk2) and Rho-kinase. Thus, our findings reveal a novel mechanism through which Ang II and PGE2 regulate peripheral vascular reactivity. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Acute and chronic role of nitric oxide, renin-angiotensin system and sympathetic nervous system in the modulation of calcium sensitization in Wistar Rats

    Czech Academy of Sciences Publication Activity Database

    Brunová, Aneta; Bencze, Michal; Behuliak, Michal; Zicha, Josef

    2015-01-01

    Roč. 64, č. 4 (2015), s. 447-457 ISSN 0862-8408 R&D Projects: GA ČR(CZ) GAP304/12/0259; GA MZd(CZ) NV15-25396A Institutional support: RVO:67985823 Keywords : blood pressure * kalcium sensitization * Rho kinase * nitric oxide * renin-angiotensin system * sympathetic nervous system * fasudil Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 1.643, year: 2015

  3. Association of renin-angiotensin system genes polymorphism with progression of diabetic nephropathy in patients with type 1 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Ilić Vesna

    2014-01-01

    Full Text Available Background/Aim. Diabetic nephropathy (DN as a major microvascular complication of diabetes mellitus (DM include a progressive increase in urinary albumin excretion in association with an increase in blood pressure and to end stage renal failure. Hypertension connected with renin-angiotensin system (RAS hyperactivity and corresponding genotypes, angiotensinogen (AGT, angiotensine-converting enzyme (ACE and angiotensin II type 1 receptor (AT1R, predispose the increasing risk of DN. The aim of this study was to assess the distribution of AGT, ACE and AT1R gene polymorphisms in patients with type 1 DM according to the level of DN and patients clinical characteristics. Methods. The study included 79 type 1 diabetic patients. Inclusion criteria were: age between 20-40, duration of diabetes > 5 years, and no other severe diseases. Clinical characteristics were gained from interviewing the patients. Polymorphism was detected by polymerase chain reaction (PCR and restriction fragment length polymorphism using restriction enzymes Psy I (Tth 111 I and Hae III. Results. The patients with proteinuria compared with normo- and microalbuminuric patients, highly differed in age, diabetes duration, blood pressure level, hypertension, rethynopathy and urinary albumin excretion values (p < 0.001. No statistically significant difference between the groups was found for the ACE and AT1R gene polymorphisms distribution. The presence of TT genotype of the M235T polymorphism was significantly higher in the group with proteinuria (p < 0.05. The patients with hypertension raised nephropathy 5.2 times higher (OR = 5.20, p < 0.05 while carriers of TT allel developed nephropathy 28.38 times higher (OR = 28.389, p < 0.01 than those with MM genotype. Conclusion. Increased association of hypertension and TT angiotensinogen gene polymorphism in patients with diabetes mellitus with proteinuria could be a significant marker of diabetic nephropathy.

  4. Renin-angiotensin system blockade reduces cardiovascular events in nonheart failure, stable patients with prior coronary intervention.

    Science.gov (United States)

    Choi, Young; Lim, Sungmin; Lee, Kwan Yong; Park, Ha-Wook; Byeon, Jaeho; Hwang, Byung-Hee; Kim, Jin Jin; Oh, Yong-Seog; Youn, Ho-Joong; Jung, Wook Sung; Seung, Ki-Bae; Chang, Kiyuk

    2018-02-27

    The effects of renin-angiotensin system (RAS) blockade on the clinical outcome in patients with stable coronary artery disease (SCAD) are conflicting. We evaluated the long-term effects of RAS blockers (angiotensin-converting enzyme inhibitor or angiotensin receptor blocker) on the clinical outcomes in patients with SCAD without heart failure (HF) who underwent percutaneous coronary intervention (PCI) with drug-eluting stent using a large-scale, multicenter, prospective cohort registry. A total of 5722 patients with SCAD were enrolled and divided into two groups according to the use of RAS blockers after PCI: RAS blocker group included 4070 patients and no RAS blocker group included 1652 patients. Exclusion criteria were left ventricular ejection fraction less than 50% and the history of HF or myocardial infarction. A major adverse cardiovascular event (MACE) was defined as a composite of cardiovascular death, nonfatal myocardial infarction, and stroke. During a median follow-up of 29.7 months, RAS blockers were associated with a significant reduction in the risk of MACE [adjusted hazard ratio (HR): 0.781; 95% confidence interval (CI): 0.626-0.975; P=0.015] and all-cause death (adjusted HR: 0.788; 95% CI: 0.627-0.990; P=0.041) but did not affect the risk of coronary revascularization. In the propensity score matched cohort, overall findings were consistent (MACE: adjusted HR: 0.679; 95% CI: 0.514-0.897; P=0.006; all-cause death: adjusted HR: 0.723; 95% CI: 0.548-0.954; P=0.022), and the benefit of RAS blockade was maintained in all predefined subgroups. This study demonstrated that RAS blockers were effective preventive therapies for reducing long-term cardiovascular events in patients with SCAD without HF who underwent PCI.

  5. A direct radioimmunoassay for aldosterone in plasma

    International Nuclear Information System (INIS)

    Lun, S.; Espiner, E.A.; Nicholls, M.G.; Yandle, T.G.

    1983-01-01

    This rapid radioimmunoassay for aldosterone is performed directly on 100 microL of unprocessed plasma, with 125 I-labeled aldosterone as the labeled antigen. Researchers use of steroid-free plasma in preparing the standard curve resulted in an overestimate of aldosterone; this problem was overcome by adding to such plasma a mixture of other steroids to provide a constant steroid/aldosterone ratio. Over a wide range of aldosterone concentrations, results agreed well between the present assay and a routine method involving solvent extraction and paper chromatography (r . 0.85), and sensitivity (20 ng/L) and inter- (10.4%) and intra- (3.9%) assay CVs were better with the present assay. This assay is especially useful for multiple samples and (or) when only small-volume samples are available

  6. The Angiotensin AT2 Receptor

    DEFF Research Database (Denmark)

    Unger, Thomas; Steckelings, Ulrike M.; Dzau, Victor J.

    2015-01-01

    Since its discovery, 25 years ago, the angiotensin AT2 receptor (AT2R) has puzzled the scientific community because of its distinct -localization, regulation, signaling pathways, and biological effects separating it clearly from the classical features of the renin-angiotensin...... system (RAS) mediated by the angiotensin AT1 receptor. Intensive research over the years has revealed major characteristics of the AT2R as a modulatory player involved in antiproliferation, anti-inflammation, natriuresis, neuroregeneration, and apoptosis, that is, -biological...

  7. Activity-guided discovery of (S)-malic acid 1'-O-β-gentiobioside as an angiotensin I-converting enzyme inhibitor in lettuce (Lactuca sativa).

    Science.gov (United States)

    Lagemann, Annika; Dunkel, Andreas; Hofmann, Thomas

    2012-07-25

    Angiotensin-converting enzyme (ACE), playing a crucial role in the renin angiotensin aldosterone system, is well-known to catalyze the conversion of the decapeptide angiotensin I into the physiologically active octapeptide angiotensin II, triggering blood pressure increasing mechanisms. To meet the demand for natural phytochemicals as antihypertensive agents in functional food development, extracts prepared from a series of vegetables were screened for their ACE-inhibitory activity by means of a LC-MS/MS-based in vitro assay. By far the highest ACE inhibition was found for a lettuce extract, in which the most active compound was located by means of activity-guided fractionation. LC-MS, NMR spectroscopy, and hydrolysis experiments followed by ion chromatography led to the unequivocal identification of the ACE inhibitor as the previously not reported (S)-malic acid 1'-O-β-gentiobioside. This glycoside represents a novel class of ACE-inhibiting phytochemicals with a low IC(50) value of 27.8 μM. First incubation experiments in saliva and aqueous hydrochloric acid demonstrated the stability of (S)-malic acid 1'-O-β-gentiobioside against salivary glycosidases and stomach acid.

  8. Does renin-angiotensin system blockade have a role in preventing diabetic retinopathy? A clinical review

    DEFF Research Database (Denmark)

    Sjølie, A K; Dodson, P; Hobbs, F R R

    2011-01-01

    Diabetes management has increasingly focused on the prevention of macrovascular disease, in particular for type 2 diabetes. Diabetic retinopathy, one of the main microvascular complications of diabetes, is also an important public health problem. Much of the care invested in retinopathy relates...... the primary trial end-points were not met, there was a clear trend to less severe retinopathy with RAS blockade. A smaller trial, RASS, reported reduced retinopathy progression in type 1 diabetes from RAS blockade with both the ARB losartan and the angiotensin converting enzyme (ACE) inhibitor enalapril...

  9. Hypoxia-Induced Collagen Synthesis of Human Lung Fibroblasts by Activating the Angiotensin System

    Directory of Open Access Journals (Sweden)

    Shan-Shan Liu

    2013-12-01

    Full Text Available The exact molecular mechanism that mediates hypoxia-induced pulmonary fibrosis needs to be further clarified. The aim of this study was to explore the effect and underlying mechanism of angiotensin II (Ang II on collagen synthesis in hypoxic human lung fibroblast (HLF cells. The HLF-1 cell line was used for in vitro studies. Angiotensinogen (AGT, angiotensin converting enzyme (ACE, angiotensin II type 1 receptor (AT1R and angiotensin II type 2 receptor (AT2R expression levels in human lung fibroblasts were analysed using real-time polymerase chain reaction (RT-PCR after hypoxic treatment. Additionally, the collagen type I (Col-I, AT1R and nuclear factor κappaB (NF-κB protein expression levels were detected using Western blot analysis, and NF-κB nuclear translocation was measured using immunofluorescence localization analysis. Ang II levels in HLF-1 cells were measured with an enzyme-linked immunosorbent assay (ELISA. We found that hypoxia increased Col-I mRNA and protein expression in HLF-1 cells, and this effect could be inhibited by an AT1R or AT2R inhibitor. The levels of NF-κB, RAS components and Ang II production in HLF-1 cells were significantly increased after the hypoxia exposure. Hypoxia or Ang II increased NF-κB-p50 protein expression in HLF-1 cells, and the special effect could be inhibited by telmisartan (TST, an AT1R inhibitor, and partially inhibited by PD123319, an AT2R inhibitor. Importantly, hypoxia-induced NF-κB nuclear translocation could be nearly completely inhibited by an AT1R or AT2R inhibitor. Furthermore pyrrolidine dithiocarbamate (PDTC, a NF-κB blocker, abolished the expression of hypoxia-induced AT1R and Col-I in HLF-1 cells. Our results indicate that Ang II-mediated NF-κB signalling via ATR is involved in hypoxia-induced collagen synthesis in human lung fibroblasts.

  10. The Brain Renin-Angiotensin System and Mitochondrial Function: Influence on Blood Pressure and Baroreflex in Transgenic Rat Strains

    Directory of Open Access Journals (Sweden)

    Manisha Nautiyal

    2013-01-01

    Full Text Available Mitochondrial dysfunction is implicated in many cardiovascular diseases, including hypertension, and may be associated with an overactive renin-angiotensin system (RAS. Angiotensin (Ang II, a potent vasoconstrictor hormone of the RAS, also impairs baroreflex and mitochondrial function. Most deleterious cardiovascular actions of Ang II are thought to be mediated by NADPH-oxidase- (NOX- derived reactive oxygen species (ROS that may also stimulate mitochondrial oxidant release and alter redox-sensitive signaling pathways in the brain. Within the RAS, the actions of Ang II are counterbalanced by Ang-(1–7, a vasodilatory peptide known to mitigate against increased oxidant stress. A balance between Ang II and Ang-(1–7 within the brain dorsal medulla contributes to maintenance of normal blood pressure and proper functioning of the arterial baroreceptor reflex for control of heart rate. We propose that Ang-(1–7 may negatively regulate the redox signaling pathways activated by Ang II to maintain normal blood pressure, baroreflex, and mitochondrial function through attenuating ROS (NOX-generated and/or mitochondrial.

  11. Farmácia Popular Program: pharmaceutical market analysis of antihypertensive acting on the renin-angiotensin system medicines.

    Science.gov (United States)

    Silva, Rondineli Mendes da; Chaves, Gabriela Costa; Chaves, Luisa Arueira; Campos, Mônica Rodrigues; Luiza, Vera Lucia; Bertoldi, Andréa Dâmaso; Ross-Degnan, Dennis; Emmerick, Isabel Cristina Martins

    2017-08-01

    This paper aims to analyse changes in the retail pharmaceutical market following policy changes in the Farmácia Popular Program (FP), a medicines subsidy program in Brazil. The retrospective longitudinal analyses focus on therapeutic class of agents acting on the renin-angiotensin system. Data obtained from QuintilesIMS (formerly IMS Health) included private retail pharmacy sales volume (pharmaceutical units) and sales values from 2002 to 2013. Analyses evaluated changes in market share following key FP policy changes. The therapeutic class was selected due to its relevance to hypertension treatment. Market share was analysed by therapeutic sub-classes and by individual company. Losartan as a single product accounted for the highest market share among angiotensin II antagonists. National companies had higher sales volume during the study period, while multinational companies had higher sales value. Changes in pharmaceutical market share coincided with the inclusion of specific products in the list of medicines covered by FP and with increases in or exemption from patient copayment.

  12. Farmácia Popular Program: pharmaceutical market analysis of antihypertensive acting on the renin-angiotensin system medicines

    Directory of Open Access Journals (Sweden)

    Rondineli Mendes da Silva

    Full Text Available Abstract This paper aims to analyse changes in the retail pharmaceutical market following policy changes in the Farmácia Popular Program (FP, a medicines subsidy program in Brazil. The retrospective longitudinal analyses focus on therapeutic class of agents acting on the renin-angiotensin system. Data obtained from QuintilesIMS (formerly IMS Health included private retail pharmacy sales volume (pharmaceutical units and sales values from 2002 to 2013. Analyses evaluated changes in market share following key FP policy changes. The therapeutic class was selected due to its relevance to hypertension treatment. Market share was analysed by therapeutic sub-classes and by individual company. Losartan as a single product accounted for the highest market share among angiotensin II antagonists. National companies had higher sales volume during the study period, while multinational companies had higher sales value. Changes in pharmaceutical market share coincided with the inclusion of specific products in the list of medicines covered by FP and with increases in or exemption from patient copayment.

  13. Side Chain-oxidized Oxysterols Regulate the Brain Renin-Angiotensin System through a Liver X Receptor-dependent Mechanism*

    Science.gov (United States)

    Mateos, Laura; Ismail, Muhammad-Al-Mustafa; Gil-Bea, Francisco-Javier; Schüle, Rebecca; Schöls, Ludger; Heverin, Maura; Folkesson, Ronnie; Björkhem, Ingemar; Cedazo-Mínguez, Angel

    2011-01-01

    Disturbances in cholesterol metabolism have been associated with hypertension and neurodegenerative disorders. Because cholesterol metabolism in the brain is efficiently separated from plasma cholesterol by the blood-brain barrier (BBB), it is an unsolved paradox how high blood cholesterol can cause an effect in the brain. Here, we discuss the possibility that cholesterol metabolites permeable to the BBB might account for these effects. We show that 27-hydroxycholesterol (27-OH) and 24S-hydroxycholesterol (24S-OH) up-regulate the renin-angiotensin system (RAS) in the brain. Brains of mice on a cholesterol-enriched diet showed up-regulated angiotensin converting enzyme (ACE), angiotensinogen (AGT), and increased JAK/STAT activity. These effects were confirmed in in vitro studies with primary neurons and astrocytes exposed to 27-OH or 24S-OH, and were partially mediated by liver X receptors. In contrast, brain RAS activity was decreased in Cyp27a1-deficient mice, a model exhibiting reduced 27-OH production from cholesterol. Moreover, in humans, normocholesterolemic patients with elevated 27-OH levels, due to a CYP7B1 mutation, had markers of activated RAS in their cerebrospinal fluid. Our results demonstrate that side chain-oxidized oxysterols are modulators of brain RAS. Considering that levels of cholesterol and 27-OH correlate in the circulation and 27-OH can pass the BBB into the brain, we suggest that this cholesterol metabolite could be a link between high plasma cholesterol levels, hypertension, and neurodegeneration. PMID:21628469

  14. Efficacy of renin-angiotensin system (RAS) blockers on cardiovascular and renal outcomes in patients with type 2 diabetes.

    Science.gov (United States)

    Cao, Zemin; Cooper, Mark E

    2012-08-01

    Cardiovascular disease is the predominant cause of morbidity in people with type 2 diabetes. Hypertension frequently coexists with diabetes and substantially increases the risk of developing end-organ damage. Controlling hypertension in patients with diabetes is therefore critical to reducing microvascular and macrovascular complications. Agents that block the renin-angiotensin system are increasingly used in patients with diabetes based on their cardiovascular and renoprotective effects, in addition to their direct effects on reducing blood pressure. Telmisartan, an angiotensin II receptor blocker (ARB), has a number of distinguishing pharmacological properties such as having the longest half-life and highest lipophilicity in its class. The ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET(®)) trial showed that telmisartan reduces cardiovascular morbidity (including myocardial infarction and stroke) in subjects with a broad spectrum of cardiovascular risk factors, including type 2 diabetes. Telmisartan is the only ARB indicated for the reduction of cardiovascular morbidity in patients with diabetes and end-organ damage, as well as in patients without diabetes but with a history of coronary artery disease, peripheral artery disease, or previous stroke. Trials of telmisartan in patients with diabetes and varying degrees of nephropathy also suggest that this drug can slow the progression of renal disease, an effect that appears to be at least partly independent of reduction in blood pressure. Telmisartan is therefore an important therapeutic option for optimizing cardiovascular and renal protection in the type 2 diabetic population.

  15. Family history and renin-angiotensin system gene polymorphisms in Chinese patients with type 2 diabetes mellitus.

    Science.gov (United States)

    Pan, Yan-Hong; Huang, Yan-Mei; Qiao, Yong-Chao; Ling, Wei; Geng, Li-Jun; Xiao, Jian-Long; Zhang, Xiao-Xi; Zhao, Hai-Lu

    2017-12-01

    A positive family history is recognized as an important risk factor for type 2 diabetes mellitus (T2DM), but the association of family history with rennin-angiotensin system (RAS) gene polymorphisms has not been reported yet, thus we aim to investigate it.Family history records, clinical and biochemical data were obtained from 1239 T2DM patients. Polymerase chain reaction (PCR) was performed for angiotensin-converting enzyme (ACE) genotyping and PCR-restricted fragment length polymorphism was used for angiotensinogen (AGT) genotyping.Patients with a negative family history had higher level of triglyceride and blood pressure, whereas those with a positive family history showed younger onset age and lower body mass index value (All P history (All P history and those with a negative family history had comparable genotype and allele distribution of ACE gene insertion/deletion polymorphisms and AGT gene M/T polymorphisms.A positive family history of diabetes was not associated with the RAS gene polymorphisms. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

  16. Combined effects of aging and inflammation on renin-angiotensin system mediate mitochondrial dysfunction and phenotypic changes in cardiomyopathies.

    Science.gov (United States)

    Burks, Tyesha N; Marx, Ruth; Powell, Laura; Rucker, Jasma; Bedja, Djahida; Heacock, Elisa; Smith, Barbara J; Foster, D Brian; Kass, David; O'Rourke, Brian; Walston, Jeremy D; Abadir, Peter M

    2015-05-20

    Although the effects of aging and inflammation on the health of the cardiac muscle are well documented, the combined effects of aging and chronic inflammation on cardiac muscle are largely unknown. The renin-angiotensin system (RAS) has been linked independently to both aging and inflammation, but is understudied in the context of their collective effect. Thus, we investigated localized cardiac angiotensin II type I and type II receptors (AT(1)R, AT(2)R), downstream effectors, and phenotypic outcomes using mouse models of the combination of aging and inflammation and compared it to a model of aging and a model of inflammation. We show molecular distinction in the combined effect of aging and inflammation as compared to each independently. The combination maintained an increased AT(1)R:AT(2)R and expression of Nox2 and exhibited the lowest activity of antioxidants. Despite signaling pathway differences, the combined effect shared phenotypic similarities with aging including oxidative damage, fibrosis, and hypertrophy. These phenotypic similarities have dubbed inflammatory conditions as premature aging, but they are, in fact, molecularly distinct. Moreover, treatment with an AT(1)R blocker, losartan, selectively reversed the signaling changes and ameliorated adverse phenotypic effects in the combination of aging and inflammation as well as each independently.

  17. ANGIOTENSIN II REGULATES ADRENAL VASCULAR TONE THROUGH ZONA GLOMERULOSA CELL-DERIVED EETS AND DHETS

    Science.gov (United States)

    Kopf, Phillip G.; Gauthier, Kathryn M.; Zhang, David X.; Falck, John R.; Campbell, William B.

    2011-01-01

    Elevated concentrations of aldosterone are associated with several cardiovascular diseases. Angiotensin II increases aldosterone secretion and adrenal blood flow. This concurrent increase in steroidogenesis and adrenal blood flow is not understood. We investigated the role of zona glomerulosa cells in the regulation of vascular tone of bovine adrenal cortical arteries by angiotensin II. Zona glomerulosa cells enhance endothelium-dependent relaxations to angiotensin II. The zona glomerulosa cell-dependent relaxations to angiotensin II are unchanged by removing the endothelium-dependent response to angiotensin II. These zona glomerulosa cell-mediated relaxations are ablated by cytochrome P450 inhibition, epoxyeicostrienoic acid antagonism, and potassium channel blockade. Analysis of zona glomerulosa cell epoxyeicosatrienoic acid production by liquid chromatography/mass spectrometry demonstrates an increase in epoxyeicosatrienoic and dihydroxyeicosatrienoic acids with angiotensin II stimulation. These epoxyeicosatrienoic and dihydroxyeicosatrienoic acids produced similar concentration-dependent relaxations of adrenal arteries, which were attenuated by epoxyeicosatrienoic acid antagonism. Whole cell potassium current of adrenal artery smooth muscle cells were increased by angiotensin II stimulation in the presence of zona glomerulosa cells but decreased in the absence of zona glomerulosa cells. This increase in potassium current was abolished by iberiotoxin. Similarly, 14,15-epoxyeicosatrienoic acid induced concentration-dependent increases in potassium current, which was abolished by iberiotoxin. Zona glomerulosa cell aldosterone release is not directly altered by epoxyeicosatrienoic acids. These data suggest that angiotensin II stimulates zona glomerulosa cells to release epoxyeicosatrienoic and dihydroxyeicosatrienoic acids, resulting in potassium channel activation and relaxation of adrenal arteries. This provides a mechanism by which Ang II concurrently increases

  18. Effects of aerobic exercise training on cardiac renin-angiotensin system in an obese Zucker rat strain.

    Directory of Open Access Journals (Sweden)

    Diego Lopes Mendes Barretti

    Full Text Available OBJECTIVE: Obesity and renin angiotensin system (RAS hyperactivity are profoundly involved in cardiovascular diseases, however aerobic exercise training (EXT can prevent obesity and cardiac RAS activation. The study hypothesis was to investigate whether obesity and its association with EXT alter the systemic and cardiac RAS components in an obese Zucker rat strain. METHODS: THE RATS WERE DIVIDED INTO THE FOLLOWING GROUPS: Lean Zucker rats (LZR; lean Zucker rats plus EXT (LZR+EXT; obese Zucker rats (OZR and obese Zucker rats plus EXT (OZR+EXT. EXT consisted of 10 weeks of 60-min swimming sessions, 5 days/week. At the end of the training protocol heart rate (HR, systolic blood pressure (SBP, cardiac hypertrophy (CH and function, local and systemic components of RAS were evaluated. Also, systemic glucose, triglycerides, total cholesterol and its LDL and HDL fractions were measured. RESULTS: The resting HR decreased (∼12% for both LZR+EXT and OZR+EXT. However, only the LZR+EXT reached significance (p<0.05, while a tendency was found for OZR versus OZR+EXT (p = 0.07. In addition, exercise reduced (57% triglycerides and (61% LDL in the OZR+EXT. The systemic angiotensin I-converting enzyme (ACE activity did not differ regardless of obesity and EXT, however, the OZR and OZR+EXT showed (66% and (42%, respectively, less angiotensin II (Ang II plasma concentration when compared with LZR. Furthermore, the results showed that EXT in the OZR prevented increase in CH, cardiac ACE activity, Ang II and AT2 receptor caused by obesity. In addition, exercise augmented cardiac ACE2 in both training groups. CONCLUSION: Despite the unchanged ACE and lower systemic Ang II levels in obesity, the cardiac RAS was increased in OZR and EXT in obese Zucker rats reduced some of the cardiac RAS components and prevented obesity-related CH. These results show that EXT prevented the heart RAS hyperactivity and cardiac maladaptive morphological alterations in obese Zucker rats.

  19. IN SILICO EVALUATION OF ANGIOTENSIN II RECEPTOR ANTAGONIST’S PLASMA PROTEIN BINDING USING COMPUTED MOLECULAR DESCRIPTORS

    Directory of Open Access Journals (Sweden)

    Jadranka Odović

    2014-03-01

    Full Text Available The discovery of new pharmacologically active substances and drugs modeling led to necessity of predicting drugs properties and its ADME data. Angiotensin II receptor antagonists are a group of pharmaceuticals which modulate the renin-angiotensin-aldosterone system and today represent the most commonly prescribed anti-hypertensive drugs. The aim of this study was to compare different molecular properties of seven angiotensin II receptor antagonists / blockers (ARBs, (eprosartan, irbesartan, losartan, olmesartan, telmisartan, valsartan and their plasma protein binding (PPB data. Several ARBs molecular descriptors were calculated using software package Molinspiration Depiction Software as well as Virtual Computational Chemistry Laboratory (electronic descriptor – PSA, constitutional parameter – Mw, geometric descriptor – Vol, lipophilicity descriptors - logP values, aqueous solubility data – logS. The correlations between all collected descriptors and plasma protein binding data obtained from relevant literature were established. In the simple linear regression poor correlations were obtained in relationships between PPB data and all calculated molecular descriptors. In the next stage of the study multiple linear regression (MLR was used for correlation of PPB data with two different descriptors as independent variables. The best correlation (R2=0.70 with P<0.05 was established between PPB data and molecular weight with addition of volume values as independent variables. The possible application of computed molecular descriptors in drugs protein binding evaluation can be of great importance in drug research.

  20. Quantification of systemic renin-angiotensin system peptides of hypertensive black and white African men established from the RAS-Fingerprint®

    Directory of Open Access Journals (Sweden)

    JM van Rooyen

    2016-10-01

    Full Text Available Objective: The objective of this study was to make use of a quantitative and qualitative approach comparing the systemic renin-angiotensin system (RAS of hypertensive black and white African men by using RAS equilibrium analysis. Materials and methods: This sub-study involved 23 black (n = 15 and white (n = 8 hypertensive men aged 39.5–41 years, living in the North West Province of South Africa. The RAS-Fingerprinting was determined with LC-MS/MS quantification of angiotensin peptides. Blood pressure and other variables were determined with known methods. Results: The main finding of this study was the significant lower Ang I (<5.0 and 45.1 pg/ml; p = 0.005 and Ang II (15.6 and 123.9 pg/ml; p ⩽ 0.001 encountered in the hypertensive black African men compared to their white counterparts. Levels of Ang 1-5 (downstream metabolite of Ang 1-7 (1.8 and 3.0 pg/ml, were detected in black and white hypertensive men, respectively. Conclusions: The observed differences between circulating RAS components, which are reflected via equilibrium angiotensin levels, point to a distinctive molecular regulation of the RAAS in the two study cohorts. The increased peripheral resistance observed in hypertensive black individuals might take over a dominant role in control of blood pressure in this study population. A novel highly sensitive LC-MS/MS method resolved the issue of peptide recovery variations during sample preparation by using internal standards for each individual angiotensin metabolite.

  1. Differences in cortical and pituitary activity in response to hypoglycaemia and cognitive testing in healthy men with different basal activity of the renin-angiotensin system

    DEFF Research Database (Denmark)

    Bie-Olsen, Lise G; Pedersen-Bjergaard, Ulrik; Kjaer, Troels W

    2010-01-01

    INTRODUCTION: High renin-angiotensin system (RAS) activity has been associated with a high risk of severe hypoglycaemia in patients with type 1 diabetes and with cognitive deterioration during experimental hypoglycaemia in healthy subjects. The aim of this study was to describe possible differenc...

  2. Phenotype standardization of angioedema in the head and neck region caused by agents acting on the angiotensin system

    NARCIS (Netherlands)

    Wadelius, M.; Marshall, S. E.; Islander, G.; Nordang, L.; Karawajczyk, M.; Yue, Q.-Y.; Terreehorst, I.; Baranova, E. V.; Hugosson, S.; Sköldefors, K.; Pirmohamed, M.; Maitland-van der Zee, A.-H.; Alfirevic, A.; Hallberg, P.; Palmer, C. N. A.

    2014-01-01

    Angioedema is a potentially life-threatening adverse reaction to angiotensin-converting enzyme inhibitors and angiotensin receptor blockers. To study the genetic etiology of this rare adverse event, international consortia and multicenter recruitment of patients are needed. To reduce patient

  3. Renin-angiotensin system antagonists and clinical outcomes in stable coronary artery disease without heart failure.

    Science.gov (United States)

    Sorbets, Emmanuel; Labreuche, Julien; Simon, Tabassome; Delorme, Laurent; Danchin, Nicolas; Amarenco, Pierre; Goto, Shinya; Meune, Christophe; Eagle, Kim A; Bhatt, Deepak L; Steg, Philippe Gabriel

    2014-07-01

    The aim of this study was to determine whether angiotensin-converting enzyme inhibitor (ACEI) or angiotensin-II receptor blocker (ARB) use is associated with lower rates of cardiovascular events in patients with stable coronary artery disease (CAD) but without heart failure (HF) receiving contemporary medical management. Using data from the Reduction of Atherothrombosis for Continued Health (REACH) registry, we examined, using propensity score approaches, relationships between cardiovascular outcomes and ACEI/ARB use (64.1% users) in 20 909 outpatients with stable CAD and free of HF at baseline. As internal control, we assessed the relation between statin use and outcomes. At 4-year follow-up, the risk of cardiovascular death, MI, or stroke (primary outcome) was similar in ACEI/ARB users compared with non-users (hazard ratio, 1.03; 95% confidence interval [CI], 0.91-1.16; P = 0.66). Similarly, the risk of the primary outcome and cardiovascular hospitalization for atherothrombotic events (secondary outcome) was not reduced in ACEI/ARB users (hazard ratio, 1.08; 95% CI, 1.01-1.16; P = 0.04), nor were the rates of any of its components. Analyses using propensity score matching yielded similar results, as did sensitivity analyses accounting for missing covariates, changes in medications over time, or analysing separately ACEI and ARB use. In contrast, in the same cohort, statin use was associated with lower rates for all outcomes. Use of ACEI/ARB was not associated with better outcomes in stable CAD outpatients without HF. The benefit of ACEI/ARB seen in randomized clinical trials was not replicated in this large contemporary cohort, which questions their value in this specific subset. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  4. A Late Diagnosis of Primary Aldosteronism.

    Science.gov (United States)

    Zorzi, Francesco; Olivieri, Oliviero; Brazzarola, Paolo; Pizzolo, Francesca

    2017-09-01

    We report the case of a 41-year-old male patient with juvenile onset refractory hypertension while taking four drugs including a diuretic. Fourteen years before he underwent a complete investigation for secondary hypertension (including the aldosterone to renin ratio-ARR) that was negative. Since that, hypertension control gradually worsened, hypertensive organ damage aggravated and hypokalemia developed in spite of ACE inhibitor treatment. At the re-evaluation ARR was elevated, and the further workup for primary aldosteronism demonstrated an unilateral aldosterone producing adenoma that was surgically removed, with subsequent optimal blood pressure control with two anti-hypertensive drugs. In this case, the failure of the first screening prevented a correct diagnosis of primary aldosteronism, with consequent inadequate blood pressure control in following years and end organ damage. The case suggests the need of clinical follow-up and eventual reappraisal of patients showing a condition of refractory hypertension associated with hypokalemia despite a first negative screening test.

  5. Is there a difference between an angiotensin-converting enzyme ...

    African Journals Online (AJOL)

    Modulation of the RAS by the two most widely used inhibitors of the system, i.e. angiotensin-converting enzyme (ACE) inhibitors and angiotensin-specific receptor blockers (ARBs) plays a crucial role in the primary and secondary prevention of cardiovascular events. These drugs both target angiotensin II, but in different.

  6. Direct renin inhibition in addition to or as an alternative to angiotensin converting enzyme inhibition in patients with chronic systolic heart failure: rationale and design of the Aliskiren Trial to Minimize OutcomeS in Patients with HEart failuRE (ATMOSPHERE) study

    DEFF Research Database (Denmark)

    Krum, Henry; Massie, Barry; Abraham, William T

    2011-01-01

    AIMS: The renin-angiotensin-aldosterone system (RAAS) represents a key therapeutic target in heart failure (HF) management. However, conventional agents that block this system induce a reflex increase in plasma renin activity (PRA), which may lead to RAAS 'escape'. Direct renin inhibitors (DRIs...... levels of BNP. Methods Patients tolerant to at least 10 mg or equivalent of enalapril will undergo an open-label run-in period where they receive enalapril then aliskiren. Approximately 7000 patients tolerating this run-in period will then be randomized 1:1:1 to aliskiren monotherapy, enalapril...

  7. Hypovolemia in syncope and orthostatic intolerance role of the renin-angiotensin system

    Science.gov (United States)

    Jacob, G.; Robertson, D.; Mosqueda-Garcia, R.; Ertl, A. C.; Robertson, R. M.; Biaggioni, I.

    1997-01-01

    PURPOSE: Orthostatic intolerance is the cause of significant disability in otherwise normal patients. Orthostatic tachycardia is usually the dominant hemodynamic abnormality, but symptoms may include dizziness, visual changes, discomfort in the head or neck, poor concentration, fatigue, palpitations, tremulousness, anxiety and, in some cases, syncope. It is the most common disorder of blood pressure regulation after essential hypertension. There is a predilection for younger rather than older adults and for women more than men. Its cause is unknown; partial sympathetic denervation or hypovolemia has been proposed. METHODS AND MATERIALS: We tested the hypothesis that reduced plasma renin activity, perhaps from defects in sympathetic innervation of the kidney, could underlie a hypovolemia, giving rise to these clinical symptoms. Sixteen patients (14 female, 2 male) ranging in age from 16 to 44 years were studied. Patients were enrolled in the study if they had orthostatic intolerance, together with a raised upright plasma norepinephrine (> or = 600 pg/mL). Patients underwent a battery of autonomic tests and biochemical determinations. RESULTS: There was a strong positive correlation between the blood volume and plasma renin activity (r = 0.84, P = 0.001). The tachycardic response to upright posture correlated with the severity of the hypovolemia. There was also a correlation between the plasma renin activity measured in these patients and their concomitant plasma aldosterone level. CONCLUSIONS: Hypovolemia occurs commonly in orthostatic intolerance. It is accompanied by an inappropriately low level of plasma renin activity. The degree of abnormality of blood volume correlates closely with the degree of abnormality in plasma renin activity. Taken together, these observations suggest that reduced plasma renin activity may be an important pathophysiologic component of the syndrome of orthostatic intolerance.

  8. Urinary renin-angiotensin markers in polycystic kidney disease.

    Science.gov (United States)

    Salih, Mahdi; Bovée, Dominique M; Roksnoer, Lodi C W; Casteleijn, Niek F; Bakker, Stephan J L; Gansevoort, Ronald T; Zietse, Robert; Danser, A H Jan; Hoorn, Ewout J

    2017-10-01

    In autosomal dominant polycystic kidney disease (ADPKD), activation of the renin-angiotensin aldosterone system (RAAS) may contribute to hypertension and disease progression. Although previous studies have focused on circulating RAAS components, preliminary evidence suggests that APDKD may increase urinary RAAS components. Therefore, our aim was to analyze circulating and urinary RAAS components in ADPKD. We cross-sectionally compared 60 patients with ADPKD with 57 patients with non-ADPKD chronic kidney disease (CKD). The two groups were matched by sex, estimated glomerular filtration rate (eGFR), blood pressure, and RAAS inhibitor use. Despite similar plasma levels of angiotensinogen and renin, urinary angiotensinogen and renin excretion were five- to sixfold higher in ADPKD ( P kidney volume correlated with plasma renin and albuminuria but not with urinary renin or angiotensinogen excretions. Albuminuria correlated positively with urinary angiotensinogen and renin excretions in ADPKD and CKD. In three ADPKD patients who underwent nephrectomy, the concentrations of albumin and angiotensinogen were highest in plasma, followed by cyst fluid and urine; urinary renin concentrations were higher than cyst fluid. In conclusion, this study shows that, despite similar circulating RAAS component levels, higher urinary excretions of angiotensinogen and renin are a unique feature of ADPKD. Future studies should address the underlying mechanism and whether this may contribute to hypertension or disease progression in ADPKD. Copyright © 2017 the American Physiological Society.

  9. Implications of Plasma Renin Activity and Plasma Aldosterone Concentration in Critically Ill Patients with Septic Shock

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    Kyung Soo Chung

    2017-05-01

    Full Text Available Background The renin-angiotensin-aldosterone system is closely associated with volume status and vascular tone in septic shock. The present study aimed to assess whether plasma renin activity (PRA and plasma aldosterone concentration (PAC measurements compared with conventional severity indicators are associated with mortality in patients with septic shock. Methods We evaluated 105 patients who were admitted for septic shock. Plasma levels of the biomarkers PRA and PAC, the PAC/PRA ratio, C-reactive protein (CRP level, and cortisol level on days 1, 3, and 7 were serially measured. During the intensive care unit stay, relevant clinical information and laboratory results were recorded. Results Patients were divided into two groups according to 28-day mortality: survivors (n = 59 and non-survivors (n = 46. The survivor group showed lower PRA, PAC, Acute Physiologic and Chronic Health Evaluation (APACHE II score, and Sequential Organ Failure Assessment (SOFA score than did the non-survivor group (all P < 0.05. The SOFA score was positively correlated with PRA (r = 0.373, P < 0.001 and PAC (r = 0.316, P = 0.001. According to receiver operating characteristic analysis, the areas under the curve of PRA and PAC to predict 28-day mortality were 0.69 (95% confidence interval [CI], 0.58 to 0.79; P = 0.001 and 0.67 (95% CI, 0.56 to 0.77; P = 0.003, respectively, similar to the APACHE II scores and SOFA scores. In particular, the group with PRA value ≥3.5 ng ml-1 h-1 on day 1 showed significantly greater mortality than did the group with PRA value <3.5 ng ml-1 h-1 (log-rank test, P < 0.001. According to multivariate analysis, SOFA score (hazard ratio, 1.11; 95% CI, 1.01 to 1.22, PRA value ≥3.5 ng ml-1 h-1 (hazard ratio, 3.25; 95% CI, 1.60 to 6.60, previous history of cancer (hazard ratio, 3.44; 95% CI, 1.72 to 6.90, and coronary arterial occlusive disease (hazard ratio, 2.99; 95% CI, 1.26 to 7.08 were predictors of 28-day mortality. Conclusions Elevated

  10. Grape-derived polyphenols improve aging-related endothelial dysfunction in rat mesenteric artery: role of oxidative stress and the angiotensin system.

    Directory of Open Access Journals (Sweden)

    Noureddine Idris Khodja

    Full Text Available Aging is characterized by the development of an endothelial dysfunction, which affects both the nitric oxide (NO- and the endothelium-derived hyperpolarizing factor (EDHF-mediated relaxations, associated with vascular oxidative stress and the activation of the angiotensin system. This study investigated whether red wine polyphenols (RWPs, antioxidants and potent stimulators of NO- and EDHF-mediated relaxations improve aging-related endothelial dysfunction, and, if so, examined the underlying mechanism. Mesenteric artery reactivity was determined in organ chambers, vascular oxidative stress by dihydroethidine and MitoSOX staining, and expression of target proteins by immunohistochemical staining. Control young rats (16 weeks received solvent (ethanol, 3% v/v, and middle-aged rats (46 weeks either solvent or RWPs (100 mg/kg/day in the drinking water. The acetylcholine-induced endothelium-dependent NO component was slightly reduced whereas the EDHF component was markedly blunted in rings of middle-aged rats compared to young rats. The endothelial dysfunction was associated with oxidative stress, an upregulation of angiotensin II and AT1 receptors and a down-regulation of SK(Ca, IK(Ca, and angiotensin converting enzyme. Intake of RWPs for either one or two weeks improved the NO and the EDHF components of the relaxation, and normalized oxidative stress, the expression of SK(Ca, IK(Ca and the components of the angiotensin system. The protective effect of the 2-week RWPs treatment persisted for one and two weeks following stopping intake of RWPs. Thus, intake of RWPs caused a persistent improvement of the endothelial function, particularly the EDHF component, in middle-aged rats and this effect seems to involve the normalization of the expression of SK(Ca, IK(Ca and the angiotensin system.

  11. Resveratrol inhibits the intracellular calcium increase and angiotensin/endothelin system activation induced by soluble uric acid in mesangial cells

    Directory of Open Access Journals (Sweden)

    G. Albertoni

    2015-01-01

    Full Text Available Resveratrol (Resv is natural polyphenol found in grapes. This study evaluated the protective effect of Resv against the effects of uric acid (UA in immortalized human mesangial cells (ihMCs. ihMCs were preincubated with Resv (12.5 µM for 1 h and treated with UA (10 mg/dL for 6 or 12 h. The intracellular calcium concentration [Ca2+]i was quantified by fluorescence using flow cytometry. Angiotensinogen (AGT and pre-pro endothelin-1 (ppET-1 mRNA were assayed by quantitative real-time RT-PCR. Angiotensin II (AII and endothelin-1 (ET-1 were assayed by ELISA. UA significantly increased [Ca2+]i. Pre-incubation with Resv significantly reduced the change in [Ca2+]i induced by UA. Incubation with UA for 6 or 12 h also increased AGT mRNA expression and AII protein synthesis. Resv blunted these increases in AGT mRNA expression and AII protein. Incubation with UA in the ihMCs increased ppET-1 expression and ET-1 protein synthesis at 6 and 12 h. When ihMCs were pre-incubated with Resv, UA had a significantly diminished effect on ppET-1 mRNA expression and ET-1 protein synthesis at 6 and 12 h, respectively. Our results suggested that UA triggers reactions including AII and ET-1 production in mesangial cells. The renin-angiotensin system may contribute to the pathogenesis of renal function and chronic kidney disease. Resv can minimize the impact of UA on AII, ET-1 and the increase of [Ca2+]i in mesangial cells, suggesting that, at least in part, Resv can prevent the effects of soluble UA in mesangial cells.

  12. Resveratrol inhibits the intracellular calcium increase and angiotensin/endothelin system activation induced by soluble uric acid in mesangial cells

    Energy Technology Data Exchange (ETDEWEB)

    Albertoni, G.; Schor, N. [Divisão de Nefrologia, Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil)

    2014-10-24

    Resveratrol (Resv) is natural polyphenol found in grapes. This study evaluated the protective effect of Resv against the effects of uric acid (UA) in immortalized human mesangial cells (ihMCs). ihMCs were preincubated with Resv (12.5 µM) for 1 h and treated with UA (10 mg/dL) for 6 or 12 h. The intracellular calcium concentration [Ca{sup 2+}]i was quantified by fluorescence using flow cytometry. Angiotensinogen (AGT) and pre-pro endothelin-1 (ppET-1) mRNA were assayed by quantitative real-time RT-PCR. Angiotensin II (AII) and endothelin-1 (ET-1) were assayed by ELISA. UA significantly increased [Ca{sup 2+}]i. Pre-incubation with Resv significantly reduced the change in [Ca{sup 2+}]i induced by UA. Incubation with UA for 6 or 12 h also increased AGT mRNA expression and AII protein synthesis. Resv blunted these increases in AGT mRNA expression and AII protein. Incubation with UA in the ihMCs increased ppET-1 expression and ET-1 protein synthesis at 6 and 12 h. When ihMCs were pre-incubated with Resv, UA had a significantly diminished effect on ppET-1 mRNA expression and ET-1 protein synthesis at 6 and 12 h, respectively. Our results suggested that UA triggers reactions including AII and ET-1 production in mesangial cells. The renin-angiotensin system may contribute to the pathogenesis of renal function and chronic kidney disease. Resv can minimize the impact of UA on AII, ET-1 and the increase of [Ca{sup 2+}]i in mesangial cells, suggesting that, at least in part, Resv can prevent the effects of soluble UA in mesangial cells.

  13. Low birth weight activates the renin–angiotensin system, but limits cardiac angiogenesis in early postnatal life

    Science.gov (United States)

    Wang, Kimberley C W; Brooks, Doug A; Summers-Pearce, Brooke; Bobrovskaya, Larisa; Tosh, Darran N; Duffield, Jaime A; Botting, Kimberley J; Zhang, Song; Caroline McMillen, I; Morrison, Janna L

    2015-01-01

    Low birth weight (LBW) is associated with increased risk of adult cardiovascular disease and this association may be partly a consequence of early programming of the renin–angiotensin system (RAS). We investigated the effects of LBW on expression of molecules in the RAS and cardiac tissue remodeling. Left ventricular samples were collected from the hearts of 21 days old lambs that were born average birth weight (ABW) and LBW. Cardiac mRNA expression was quantified using real-time RT-PCR and protein expression was quantified using Western blotting. DNA methylation and histone acetylation were assessed by combined bisulfite restriction analysis and chromatin immunoprecipitation, respectively. There were increased plasma renin activity, angiotensin I (ANGI), and ANGII concentrations in LBW compared to ABW lambs at day 20. In LBW lambs, there was increased expression of cardiac ACE2 mRNA, decreased ANGII receptor type 1 (AT1R) protein, and acetylation of histone H3K9 of the AT1R promoter but no changes in AT1R mRNA expression and AT1R promoter DNA methylation. There was no difference in the abundance of proteins involved in autophagy or fibrosis. BIRC5 and VEGF mRNA expression was increased; however, the total length of the capillaries was decreased in the hearts of LBW lambs. Activation of the circulating and local cardiac RAS in neonatal LBW lambs may be expected to increase cardiac fibrosis, autophagy, and capillary length. However, we observed only a decrease in total capillary length, suggesting a dysregulation of the RAS in the heart of LBW lambs and this may have significant implications for heart health in later life. PMID:25649246

  14. Low birth weight activates the renin-angiotensin system, but limits cardiac angiogenesis in early postnatal life.

    Science.gov (United States)

    Wang, Kimberley C W; Brooks, Doug A; Summers-Pearce, Brooke; Bobrovskaya, Larisa; Tosh, Darran N; Duffield, Jaime A; Botting, Kimberley J; Zhang, Song; Caroline McMillen, I; Morrison, Janna L

    2015-02-01

    Low birth weight (LBW) is associated with increased risk of adult cardiovascular disease and this association may be partly a consequence of early programming of the renin-angiotensin system (RAS). We investigated the effects of LBW on expression of molecules in the RAS and cardiac tissue remodeling. Left ventricular samples were collected from the hearts of 21 days old lambs that were born average birth weight (ABW) and LBW. Cardiac mRNA expression was quantified using real-time RT-PCR and protein expression was quantified using Western blotting. DNA methylation and histone acetylation were assessed by combined bisulfite restriction analysis and chromatin immunoprecipitation, respectively. There were increased plasma renin activity, angiotensin I (ANGI), and ANGII concentrations in LBW compared to ABW lambs at day 20. In LBW lambs, there was increased expression of cardiac ACE2 mRNA, decreased ANGII receptor type 1 (AT1R) protein, and acetylation of histone H3K9 of the AT1R promoter but no changes in AT1R mRNA expression and AT1R promoter DNA methylation. There was no difference in the abundance of proteins involved in autophagy or fibrosis. BIRC5 and VEGF mRNA expression was increased; however, the total length of the capillaries was decreased in the hearts of LBW lambs. Activation of the circulating and local cardiac RAS in neonatal LBW lambs may be expected to increase cardiac fibrosis, autophagy, and capillary length. However, we observed only a decrease in total capillary length, suggesting a dysregulation of the RAS in the heart of LBW lambs and this may have significant implications for heart health in later life. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  15. Role of angiotensin II and endothelin-1 receptors in aging-related functional changes in rat cardiovascular system.

    Science.gov (United States)

    Ishihata, Akira; Katano, Yumi

    2006-05-01

    Angiotensin II (AII) and endothelin-1 (ET-1) are regarded as key players in the age-related changes in cardiovascular function. They are known to be involved in the pathogenesis of cardiac fibrosis and coronary vascular atherosclerosis. AII- and ET-induced vasoconstriction was augmented in coronary arteries of Langendorff-perfused heart from aged rats. In papillary muscles, ET-1-induced positive inotropic effect (PIE) was diminished by aging. On the other hand, both ET-1 and AII caused greater vasoconstriction in aged rat coronary arteries compared to those in the young rat. To further elucidate the mechanism of these age-dependent changes in cardiovascular effects of ET-1 and AII, we examined the expression of AII and ET-1 receptors in young (2-month-old) and aged (24-month-old) rats. Total RNA was isolated from left ventricles. For determination of the gene expression of AT(1) receptor and ET(A)/ET(B) receptor mRNA, competitive RT-PCR and Northern blot analysis were performed, respectively. [(125)I]ET-1 receptor assay was carried out in left ventricular membrane fraction. AT(1)-receptor, ET(A)-, and ET(B)-receptor mRNA were upregulated in the left ventricles of senescent rats compared with young ones. The affinity of ET-1-receptor was not changed, but receptor density was significantly increased in aged rats. Although the precise mechanism for the upregulation of AT(1) receptor and ET-1 receptor in the aged rat heart has not been clarified yet, these findings suggest that the activation of the renin-angiotensin system as well as ET receptor may be important for the physiological changes in aged hearts.

  16. Structural characterization of angiotensin I-converting enzyme in complex with a selenium analogue of captopril

    Science.gov (United States)

    Akif, Mohd; Masuyer, Geoffrey; Schwager, Sylva L U; Bhuyan, Bhaskar J; Mugesh, Govindasamy; Isaac, R Elwyn; Sturrock, Edward D; Acharya, K Ravi

    2011-01-01

    Human somatic angiotensin I-converting enzyme (ACE), a zinc-dependent dipeptidyl carboxypeptidase, is central to the regulation of the renin–angiotensin aldosterone system. It is a well-known target for combating hypertension and related cardiovascular diseases. In a recent study by Bhuyan and Mugesh [Org. Biomol. Chem. (2011) 9, 1356–1365], it was shown that the selenium analogues of captopril (a well-known clinical inhibitor of ACE) not only inhibit ACE, but also protect against peroxynitrite-mediated nitration of peptides and proteins. Here, we report the crystal structures of human testis ACE (tACE) and a homologue of ACE, known as AnCE, from Drosophila melanogaster in complex with the most promising selenium analogue of captopril (SeCap) determined at 2.4 and 2.35 Å resolution, respectively. The inhibitor binds at the active site of tACE and AnCE in an analogous fashion to that observed for captopril and provide the first examples of a protein–selenolate interaction. These new structures of tACE–SeCap and AnCE–SeCap inhibitor complexes presented here provide important information for further exploration of zinc coordinating selenium-based ACE inhibitor pharmacophores with significant antioxidant activity. Database Structural data for the two SeCap complexes with ACE and AnCE have been deposited with the RCSB Protein Data Bank under the codes 2YDM and 3ZQZ, respectively. PMID:21810173

  17. Angiotensin Converting Enzyme Inhibitor-related Angioedema: A Case of an Unexpected Death.

    Science.gov (United States)

    Atalay, Eray; Özdemir, Mehmet Tamer; Çiğsar, Gülşen; Omurca, Ferhat; Aslan, Nurullah; Yildiz, Mehmet; Gey, Zehra Bahar

    2015-12-01

    Angioedema is an asymmetric non-pitting oedema on face, lips, tongue and mucous membranes; any delay in diagnosis and treatment can be fatal. Treatment with lisinopril as an angiotensin converting enzyme (ACE) inhibitor, can be a reason of angioedema. Here we report a case who developed oral-facial edema four years after using lisinopril/hydrochlorothiazide. Laryngeal oedema is a main cause of death in angioedema. The treatment of choice in angioedema including fresh frozen plasma, C1 inhibitor concentrations and BRK-2 antagonists (bradykinin B2 receptor antagonists) were used. In this case; a 77 years old female patient suffering from hypertension was considered. This patient was suffering two days from swelling on her face and neck. Non- allergic angioedema was distinguished in five major forms; acquired (AAO), hereditary (HAE), renin-angiotensin-aldosterone system (RAAS) blocker-dependent, pseudoallergic angioedema (PAS) and an idiopathic angioedema (IAO). She was admitted to our clinic with the diagnosis of hereditary angioedema. Patient had skin edema and life threatening laryngeal edema. In emergency department treatment was started using intravenous methylprednisolone, diphenydramine as well as inhaled and subcutaneous epinephrine simultaneously. Despite the initial treatment, the patient died due to the insufficient respiration and cardiac arrest. The patient has no history of kidney disease.

  18. The influence of certain molecular descriptors of fecal elimination of angiotensin II receptor antagonists

    Directory of Open Access Journals (Sweden)

    Trbojević-Stanković Jasna B.

    2015-01-01

    Full Text Available Angiotensin II receptor antagonists (ARBs modulate the function of the renin-angiotensin-aldosterone system and are commonly prescribed antihypertensive drugs, especially in patients with renal failure. In this study, the relationship between several molecular properties of seven ARBs (candesartan, eprosartan, irbesartan, losartan, olmesartan, telmisartan, valsartan and their fecal elimination data obtained from the literature were investigated. The ARB molecular descriptors were calculated using three software packages. Simple linear regression analysis showed the best 2 correlation between fecal elimination data and lipophilicity descriptor, ClogP values (R2 = 0.725. Multiple linear regression was applied to examine the correlation of ARBs’ fecal elimination data with their lipophilicity and one additional, calculated descriptor. The best correlation (R2 = 0.909 with an acceptable probability value, P <0.05 was established between the ARB fecal elimination data and their lipophilicity and aqueous solubility data. Applying computed molecular descriptors for evaluating drug elimination is of great importance in drug research.

  19. Moderation of dietary sodium potentiates the renal and cardiovascular protective effects of angiotensin receptor blockers.

    Science.gov (United States)

    Lambers Heerspink, Hiddo J; Holtkamp, Frank A; Parving, Hans-Henrik; Navis, Gerjan J; Lewis, Julia B; Ritz, Eberhard; de Graeff, Pieter A; de Zeeuw, Dick

    2012-08-01

    Dietary sodium restriction has been shown to enhance the short-term response of blood pressure and albuminuria to angiotensin receptor blockers (ARBs). Whether this also enhances the long-term renal and cardiovascular protective effects of ARBs is unknown. Here we conducted a post-hoc analysis of the RENAAL and IDNT trials to test this in patients with type 2 diabetic nephropathy randomized to ARB or non-renin-angiotensin-aldosterone system (non-RAASi)-based antihypertensive therapy. Treatment effects on renal and cardiovascular outcomes were compared in subgroups based on dietary sodium intake during treatment, measured as the 24-h urinary sodium/creatinine ratio of 1177 patients with available 24-h urinary sodium measurements. ARB compared to non-RAASi-based therapy produced the greatest long-term effects on renal and cardiovascular events in the lowest tertile of sodium intake. Compared to non-RAASi, the trend in risk for renal events was significantly reduced by 43%, not changed, or increased by 37% for each tertile of increased sodium intake, respectively. The trend for cardiovascular events was significantly reduced by 37%, increased by 2% and 25%, respectively. Thus, treatment effects of ARB compared with non-RAASi-based therapy on renal and cardiovascular outcomes were greater in patients with type 2 diabetic nephropathy with lower than higher dietary sodium intake. This underscores the avoidance of excessive sodium intake, particularly in type 2 diabetic patients receiving ARB therapy.

  20. Nifedipine-sensitive blood pressure component in hypertensive models characterized by high activity of either sympathetic nervous system or renin-angiotensin system

    Czech Academy of Sciences Publication Activity Database

    Zicha, Josef; Dobešová, Zdenka; Behuliak, Michal; Pintérová, Mária; Kuneš, Jaroslav; Vaněčková, Ivana

    2014-01-01

    Roč. 63, č. 1 (2014), s. 13-26 ISSN 0862-8408 R&D Projects: GA MŠk(CZ) 1M0510; GA ČR(CZ) GA305/09/0336; GA ČR(CZ) GAP304/12/0259 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : voltage-gated caclium channels * sympathetic nervous system * renin-angiotensin system * nitric oxide Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 1.293, year: 2014

  1. Localization of aldosterone-producing tumours in primary aldosteronism by adrenal and renal vein catheterization

    DEFF Research Database (Denmark)

    Lund, J O; Nielsen, M D; Giese, Jacob

    1980-01-01

    Regional venous plasma aldosterone concentrations were determined and assessed against concurrent arterial levels in 16 patients with primary aldosteronism. The results obtained by sampling from the left adrenal vein or the left renal vein allowed correct side prediction of the presupposed adenoma...

  2. A method to evaluate the renin-angiotensin system in rat renal cortex using a microdialysis technique combined with HPLC-fluorescence detection.

    Science.gov (United States)

    Kajiro, Toshi; Nakajima, Yuki; Fukushima, Takeshi; Imai, Kazuhiro

    2002-09-01

    A microdialysis (MD) technique, combined with HPLC-fluorescence (FL) detection, was developed for the evaluation of the tissue-specific renin-angiotensin system (RAS) in the rat renal cortex. An MD probe constructed with a hydrophilic hollow fiber dialysis tubing, AN69, showed high recovery (more than 50%) in vitro for all four angiotensins: angiotensin I (Ang I), Ang II, Ang III, and Ang (1-7). Angiotensins, successfully derivatized with m-BS-ABD-F, a water-soluble fluorogenic reagent that has a 2,1,3-benzoxadiazole (benzofurazan) structure, could be simultaneously determined by coupled-column HPLC. The detection limit for Ang I, Ang II, Ang III, and Ang (1-7) were 94, 44, 47, and 83 fmol, respectively. All these peptides were determined with good linearity (0.0125-3.1 microM, equivalent to 0.25-62 pmol, correlation coefficient >0.99) and good precision (recovery >91%). In the MD studies, generation of Ang (1-7) and Ang II was observed when Ang I was perfused, and Ang (1-7) was the major biologically active angiotensin found in the dialysate samples. The concentration of Ang (1-7) and Ang II in the dialysate samples showed good correlation to that of Ang I in a MD perfusate (20-100 microM). Cleavage of Ang I to Ang (1-7) was drastically suppressed by the co-perfusion of phoshoramidon (0.5-5 mM), an inhibitor of neprilysin, which generates Ang (1-7) from Ang I. These results are consistent with the previously reported characteristics of tissue-specific renal RAS, suggesting that our MD/HPLC-FL system may have the potential to be employed to evaluate tissue-specific RAS in the rat renal cortex.

  3. Angiotensin II and taste sensitivity

    Directory of Open Access Journals (Sweden)

    Noriatsu Shigemura, DDS, PhD

    2015-05-01

    Full Text Available The sense of taste plays a major role in evaluating the quality of food components in the oral cavity. Sweet, salty, umami, sour and bitter taste are generally accepted as five basic taste qualities. Among them, salty taste is attractive to animals and influences sodium intake. Angiotensin II (ANG II and aldosterone (ALDO, which is stimulated by ANG II are key hormones that regulate sodium homeostasis and water balance. At the peripheral gustatory organs, it has been reported that ALDO increases the amiloride-sensitivity of the rat gustatory neural responses to NaCl in a time course of several hours. A recent study demonstrated that ANG II suppresses amiloride-sensitivity of the mouse gustatory and behavioral responses to NaCl via its receptor AT1 within an hour. Moreover, ANG II enhances sweet taste sensitivity without affecting umami, sour and bitter tastes. These results suggest that the reciprocal and sequential regulatory mechanisms by ANG II (as an acute suppressor together with ALDO (as a slow enhancer on the salt taste sensitivity may exist in peripheral taste organs, contribute to salt intake, and play an important role in sodium homeostasis. Furthermore, the linkage between salty and sweet taste modulations via the ANG II signaling may optimize sodium and calorie intakes.

  4. Effects of natural peptides from food proteins on angiotensin converting enzyme activity and hypertension.

    Science.gov (United States)

    Martin, Melanie; Deussen, Andreas

    2017-12-15

    Cardiovascular diseases are the leading cause of death. The underlying pathophysiology is largely contributed by an overactivation of the renin-angiotensin-aldosterone-system (RAAS). Herein, angiotensin II (AngII) is a key mediator not only in blood pressure control and vascular tone regulation, but also involved in inflammation, endothelial dysfunction, atherosclerosis, hypertension and congestive heart failure. Since more than three decades suppression of AngII generation by inhibition of the angiotensin-converting enzyme (ACE) or blockade of the AngII-receptor has shown clinical benefit by reducing hypertension, atherosclerosis and other inflammation-associated cardiovascular diseases. Besides pharmaceutical ACE-inhibitors some natural peptides derived from food proteins reduce in vitro ACE activity. Several animal studies and a few human clinical trials have shown antihypertensive effects of such peptides, which might be attractive as food additives to prevent age-related RAAS activation. However, their inhibitory potency on in vitro ACE activity does not always correlate with an antihypertensive impact. While some peptides with high inhibitory activity on ACE-activity in vitro show no antihypertensive effect in vivo, other peptides with only a moderate ACE inhibitory activity in vitro cause such effects. The explanation for this conflicting phenomenon between inhibitory activity and antihypertensive effect remains unclear to date. This review shall critically address the effects of natural peptides derived from different food proteins on the cardiovascular system and the possible underlying mechanisms. A central aspect will be to point to conceptual gaps in the current understanding of the action of these peptides with respect to in vivo blood pressure lowering effects.

  5. Effects of treatment with β-blocker and aldosterone antagonist on central and peripheral haemodynamics and oxygenation in cirrhosis

    DEFF Research Database (Denmark)

    Winkler, Christine; Hobolth, Lise; Krag, Aleksander

    2011-01-01

    Patients with cirrhosis often exhibit abnormalities in cardiovascular regulation and oxygenation. Many of these patients are treated with β-blockers and aldosterone antagonists that may influence the regulation of systemic haemodynamics, but the specific effects on systemic haemodynamics and oxyg......Patients with cirrhosis often exhibit abnormalities in cardiovascular regulation and oxygenation. Many of these patients are treated with β-blockers and aldosterone antagonists that may influence the regulation of systemic haemodynamics, but the specific effects on systemic haemodynamics...

  6. Angiotensin II in the paraventricular nucleus stimulates sympathetic outflow to the cardiovascular system and make vasopressin release in rat.

    Science.gov (United States)

    Khanmoradi, Mehrangiz; Nasimi, Ali

    2016-10-06

    The hypothalamic paraventricular nucleus (PVN) plays essential roles in neuroendocrine and autonomic functions, including cardiovascular regulation. It was shown that microinjection of angiotensin II (AngII) into the PVN produced a pressor response. In this study, we explored the probable mechanisms of this pressor response. AngII was microinjected into the PVN and cardiovascular responses were recorded. Then, the responses were re-tested after systemic injection of a ganglionic blocker, Hexamethonium, or a vasopressin V1 receptor blocker. Hexamethonium pretreatment (i.v.) greatly and significantly attenuated the pressor response to AngII, with no significant effect on heart rate, indicating that the sympathetic system is involved in the cardiovascular effect of AngII in the PVN. Systemic pretreatment (i.v.) with V1 antagonist greatly and significantly attenuated the pressor response to AngII, with no significant effect on heart rate, indicating that vasopressin release is involved in the cardiovascular effect of AngII in the PVN. Overall, we found that AngII microinjected into the PVN produced a pressor response mediated by the sympathetic system and vasopressin release, indicating that other than circulating AngII, endogenous AngII of the PVN increases the vasopressin release from the PVN. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. Phenotype Standardization of Angioedema in the Head and Neck Region Caused by Agents Acting on the Angiotensin System

    Science.gov (United States)

    Wadelius, M; Marshall, S E; Islander, G; Nordang, L; Karawajczyk, M; Yue, Q-Y; Terreehorst, I; Baranova, E V; Hugosson, S; Sköldefors, K; Pirmohamed, M; Maitland-van der Zee, A-H; Alfirevic, A; Hallberg, P; Palmer, C N A

    2014-01-01

    Angioedema is a potentially life-threatening adverse reaction to angiotensin-converting enzyme inhibitors and angiotensin receptor blockers. To study the genetic etiology of this rare adverse event, international consortia and multicenter recruitment of patients are needed. To reduce patient heterogeneity, we have standardized the phenotype. In brief, it comprises swelling in the head and neck region that first occurs during treatment. It should not coincide with urticaria or have another likely cause such as hereditary angioedema. PMID:24960520

  8. Effect of Uric Acid Lowering on Renin-Angiotensin-System Activation and Ambulatory BP: A Randomized Controlled Trial.

    Science.gov (United States)

    McMullan, Ciaran J; Borgi, Lea; Fisher, Naomi; Curhan, Gary; Forman, John

    2017-05-08

    Higher serum uric acid levels, even within the reference range, are strongly associated with increased activity of the renin-angiotensin system (RAS) and risk of incident hypertension. However, the effect of lowering serum uric acid on RAS activity in humans is unknown, although the data that lowering serum uric acid can reduce BP are conflicting. In a double-blind placebo-controlled trial conducted from 2011 to 2015, we randomly assigned 149 overweight or obese adults with serum uric acid ≥5.0 mg/dl to uric acid lowering with either probenecid or allopurinol, or to placebo. The primary endpoints were kidney-specific and systemic RAS activity. Secondary endpoints included mean 24-hour systolic BP, mean awake and asleep BP, and nocturnal dipping. Allopurinol and probenecid markedly lowered serum uric acid after 4 and 8 weeks compared with placebo (mean serum uric acid in allopurinol, probenecid, and placebo at 8 weeks was 2.9, 3.5, and 5.6 mg/dl, respectively). The change in kidney-specific RAS activity, measured as change in the median (interquartile range) renal plasma flow response to captopril (in ml/min per 1.73 m 2 ) from baseline to 8 weeks, was -4 (-25 to 32) in the probenecid group ( P =0.83), -4 (-16 to 9) in the allopurinol group ( P =0.32), and 1 (-21 to 17) in the placebo group ( P =0.96), with no significant treatment effect ( P =0.77). Similarly, plasma renin activity and plasma angiotensin II levels did not significantly change with treatment. The change in mean (±SD) 24-hour systolic BPs from baseline to 8 weeks was -1.6±10.1 with probenecid ( P =0.43), -0.4±6.1 with allopurinol ( P =0.76), and 0.5±6.0 with placebo ( P =0.65); there was no significant treatment effect ( P =0.58). Adverse events occurred in 9%, 12%, and 2% of those given probenecid, allopurinol, or placebo, respectively. In contrast to animal experiments and observational studies, this randomized, placebo-controlled trial found that uric acid lowering had no effect on kidney

  9. DOCA stimulates salt appetite in Zucker rats: effect of dose, synergistic action with central angiotensin II, and obesity.

    Science.gov (United States)

    Omouessi, S T; Falconetti, C; Fernette, B; Thornton, S N

    2007-09-14

    An enhanced sodium appetite is found in rats by the synergist interaction of peripheral mineralocorticoids, deoxycorticosterone acetate (DOCA), and central angiotensin II (AngII), the synergy theory. We used obese Zucker rats which have a predisposition to develop hypertension under appropriate salt conditions to examine this synergy response between AngII and different low doses of DOCA on 2% NaCl intake. Obese and lean Zucker rats on low sodium food were treated systemically with 0.5, 1 and 2 mg/kg/day of DOCA for 3 days, before receiving i.c.v. AngII (10 pmol) on the fourth day. Food, fluid intakes and urine outputs were measured daily throughout. Plasma aldosterone levels were also analysed. Results showed that AngII alone increased water but not salt intake, whereas all three doses of DOCA by themselves enhanced daily salt intake during the treatment period. The lowest dose of DOCA plus AngII did not stimulate an enhanced sodium consumption. The 1 mg/kg was the threshold dose of DOCA for a synergistic response, and with 2 mg/kg DOCA the obese rats consumed nearly 2-fold more hypertonic NaCl solution than the leans. Moreover, obese baseline plasma levels of aldosterone were more elevated than the lean rats. In conclusion, in adult Zucker rats a threshold level of mineralocorticoid is required for the salt stimulating action of central AngII. In the obese rat the synergistic effect is enhanced with higher doses of mineralocorticoid, suggesting that the plasma level of aldosterone could be a prominent factor, which may predispose the obese to salt-sensitivity and, possibly, subsequently to hypertension under appropriate conditions.

  10. Acute Total and Chronic Partial Sleep Deprivation: Effects on Neurobehavioral Functions, Waking EEG and Renin-Angiotensin System

    Science.gov (United States)

    Dijk, Derk-Jan

    1999-01-01

    protocol of the Quantitative EEG and Waking Neurobehavioral Function project. This will allow us to investigate two additional specific aims: 1) Test the hypothesis that chronic partial sleep deprivation during a 17 day bed rest experiment results in deterioration of neurobehavioral function during waking and increases in EEG power density in the theta frequencies, especially in frontal areas of the brain, as well as the nonREM- REM cycle dependent modulation of heart-rate variability. 2) Test the hypothesis that acute total sleep deprivation modifies the circadian rhythm of the renin-angiotensin system, changes the acute responsiveness of this system to posture beyond what a microgravity environment alone does and affects the nonREM-REM cycle dependent modulation of heart-rate variability.

  11. The effect of vitamin D on renin-angiotensin system activation and blood pressure: a randomized control trial.

    Science.gov (United States)

    McMullan, Ciaran J; Borgi, Lea; Curhan, Gary C; Fisher, Naomi; Forman, John P

    2017-04-01

    Disruption of vitamin D signaling in rodents causes activation of the rennin-angiotensin system (RAS) and development of hypertension. Observational studies in humans found lower circulating 25-hydroxyvitamin D [25(OH)D] is associated with increased RAS activity and blood pressure (BP). We performed the first randomized control trial to investigate the effects of vitamin D supplementation on the RAS in humans. Vitamin D deficient, [25(OH)D ≤20 ng/ml), overweight individuals without hypertension were randomized into a double-blind, placebo-controlled trial of 8-weeks treatment with ergocalciferol or placebo. Kidney-specific RAS activity, measured using renal plasma flow response to captopril in high sodium balance, was assessed at baseline and 8 weeks, as was systemic RAS activity and 24-h ambulatory BP. In total, 84 participants completed the study. Mean 25[OH]D levels increased from 14.7 to 30.3 ng/ml in the ergocalciferol group, P value vitamin D deficiency on RAS activity or BP after 8 weeks. These findings are not consistent with the hypothesis that vitamin D is a modifiable target for lowering BP in vitamin D deficient individuals.

  12. Inhibition of the Renin-Angiotensin System Post Myocardial Infarction Prevents Inflammation-Associated Acute Cardiac Rupture.

    Science.gov (United States)

    Gao, Xiao-Ming; Tsai, Alan; Al-Sharea, Annas; Su, Yidan; Moore, Shirley; Han, Li-Ping; Kiriazis, Helen; Dart, Anthony M; Murphy, Andrew J; Du, Xiao-Jun

    2017-04-01

    Inhibition of the renin-angiotensin system (RAS) is beneficial in patient management after myocardial infarction (MI). However, whether RAS inhibition also provides cardiac protection in the acute phase of MI is unclear. Male 129sv mice underwent coronary artery occlusion to induce MI, followed by treatment with losartan (L, 20 and 60 mg/kg), perindopril (P, 2 and 6 mg/kg), amlodipine (20 mg/kg as a BP-lowering agent) or vehicle as control. Drug effects on hemodynamics were examined. Effects of treatments on incidence of cardiac rupture, haematological profile, monocyte and neutrophil population in the spleen and the heart, cardiac leukocyte density, expression of inflammatory genes and activity of MMPs were studied after MI. Incidence of cardiac rupture within 2 weeks was significantly and similarly reduced by both losartan (L) and perindopril (P) in a dose-dependent manner [75% (27/36) in vehicle, 40-45% in low-dose (L 10/22, P 8/20) and 16-20% (L 5/32, P 4/20) in high-dose groups, all P infarct tissue were attenuated by losartan and/or perindopril treatment (all P acute phase of MI through blockade of splenic release of monocytes and neutrophils and consequently attenuation of systemic and regional inflammatory responses.

  13. Exercise attenuates dexamethasone-induced hypertension through an improvement of baroreflex activity independently of the renin-angiotensin system.

    Science.gov (United States)

    Constantino, Paula B; Dionísio, Thiago J; Duchatsch, Francine; Herrera, Naiara A; Duarte, Josiane O; Santos, Carlos F; Crestani, Carlos C; Amaral, Sandra L

    2017-12-01

    Dexamethasone-induced hypertension may be caused by baroreflex alterations or renin-angiotensin system (RAS) exacerbation. Aerobic training has been recommended for hypertension treatment, but the mechanisms responsible for reduction of arterial pressure (AP) in dexamethasone (DEX) treated rats are still inconclusive.This study evaluated whether mechanisms responsible for training-induced attenuation of hypertension involve changes in autonomic nervous system and in RAS components. Rats underwent aerobic training protocol on treadmill or were kept sedentary for 8 weeks. Additionally, animals were treated with DEX during the last 10 days of exercise. Body weight (BW), AP and baroreflex activity were analyzed. Tibialis anterior (TA), soleus (SOL) and left ventricle (LV) were collected for evaluation of RAS components gene expression and protein levels. Dexamethasone decreased BW (20%), caused TA atrophy (16%) and increased systolic AP (SAP, 16%) as well as decreased baroreflex activity. Training attenuated SAP increase and improved baroreflex activity, although it did not prevent DEX-induced BW reduction and muscle atrophy. Neither DEX nor training caused expressive changes in RAS components. In conclusion, exercise training was effective in attenuating hypertension induced by DEX and this response may be mediated by a better autonomic balance through an improvement of baroreflex activity rather than changes in RAS components. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. CACNA1H(M1549V) Mutant Calcium Channel Causes Autonomous Aldosterone Production in HAC15 Cells and Is Inhibited by Mibefradil.

    Science.gov (United States)

    Reimer, Esther N; Walenda, Gudrun; Seidel, Eric; Scholl, Ute I

    2016-08-01

    We recently demonstrated that a recurrent gain-of-function mutation in a T-type calcium channel, CACNA1H(M1549V), causes a novel Mendelian disorder featuring early-onset primary aldosteronism and hypertension. This variant was found independently in five families. CACNA1H(M1549V) leads to impaired channel inactivation and activation at more hyperpolarized potentials, inferred to cause increased calcium entry. We here aimed to study the effect of this variant on aldosterone production. We heterologously expressed empty vector, CACNA1H(WT) and CACNA1H(M1549V) in the aldosterone-producing adrenocortical cancer cell line H295R and its subclone HAC15. Transfection rates, expression levels, and subcellular distribution of the channel were similar between CACNA1H(WT) and CACNA1H(M1549V). We measured aldosterone production by an ELISA and CYP11B2 (aldosterone synthase) expression by real-time PCR. In unstimulated cells, transfection of CACNA1H(WT) led to a 2-fold increase in aldosterone levels compared with vector-transfected cells. Expression of CACNA1H(M1549V) caused a 7-fold increase in aldosterone levels. Treatment with angiotensin II or increased extracellular potassium levels further stimulated aldosterone production in both CACNA1H(WT)- and CACNA1H(M1549V)-transfected cells. Similar results were obtained for CYP11B2 expression. Inhibition of CACNA1H channels with the T-type calcium channel blocker Mibefradil completely abrogated the effects of CACNA1H(WT) and CACNA1H(M1549V) on CYP11B2 expression. These results directly link CACNA1H(M1549V) to increased aldosterone production. They suggest that calcium channel blockers may be beneficial in the treatment of a subset of patients with primary aldosteronism. Such blockers could target CACNA1H or both CACNA1H and the L-type calcium channel CACNA1D that is also expressed in the adrenal gland and mutated in patients with primary aldosteronism.

  15. Common angiotensin receptor blockers may directly modulate the immune system via VDR, PPAR and CCR2b

    Directory of Open Access Journals (Sweden)

    Lee Robert E

    2006-01-01

    Full Text Available Abstract Background There have been indications that common Angiotensin Receptor Blockers (ARBs may be exerting anti-inflammatory actions by directly modulating the immune system. We decided to use molecular modelling to rapidly assess which of the potential targets might justify the expense of detailed laboratory validation. We first studied the VDR nuclear receptor, which is activated by the secosteroid hormone 1,25-dihydroxyvitamin-D. This receptor mediates the expression of regulators as ubiquitous as GnRH (Gonadatrophin hormone releasing hormone and the Parathyroid Hormone (PTH. Additionally we examined Peroxisome Proliferator-Activated Receptor Gamma (PPARgamma, which affects the function of phagocytic cells, and the C-CChemokine Receptor, type 2b, (CCR2b, which recruits monocytes to the site of inflammatory immune challenge. Results Telmisartan was predicted to strongly antagonize (Ki≈0.04nmol the VDR. The ARBs Olmesartan, Irbesartan and Valsartan (Ki≈10 nmol are likely to be useful VDR antagonists at typical in-vivo concentrations. Candesartan (Ki≈30 nmol and Losartan (Ki≈70 nmol may also usefully inhibit the VDR. Telmisartan is a strong modulator of PPARgamma (Ki≈0.3 nmol, while Losartan (Ki≈3 nmol, Irbesartan (Ki≈6 nmol, Olmesartan and Valsartan (Ki≈12 nmol also seem likely to have significant PPAR modulatory activity. Olmesartan andIrbesartan (Ki≈9 nmol additionally act as antagonists of a theoretical modelof CCR2b. Initial validation of this CCR2b model was performed, and a proposed model for the AngiotensinII Type1 receptor (AT2R1 has been presented. Conclusion Molecular modeling has proven valuable to generate testable hypotheses concerning receptor/ligand binding and is an important tool in drug design. ARBs were designed to act as antagonists for AT2R1, and it was not surprising to discover their affinity for the structurally similar CCR2b. However, this study also found evidence that ARBs modulate the

  16. Epistatic Effects of Polymorphisms in Genes from the Renin-Angiotensin, Bradykinin, and Fibrinolytic Systems on Plasma t-PA and PAI-1 Levels

    Science.gov (United States)

    Asselbergs, Folkert W.; Williams, Scott M.; Hebert, Patricia R.; Coffey, Christopher S.; Hillege, Hans L.; Navis, Gerjan; Vaughan, Douglas E.; van Gilst, Wiek H.; Moore, Jason H.

    2007-01-01

    Tissue plasminogen activator (t-PA) and plasminogen activator inhibitor 1 (PAI-1) directly influence thrombus formation and degradation and thereby risk for arterial thrombosis. Activation of the renin-angiotensin system has been linked to the production of PAI-1 expression via the angiotensin II type 1 receptor (AT1R). In addition, bradykinin can induce the release of t-PA through a B2 receptor mechanism. In the present study, we aimed to investigate the epistatic effects of polymorphisms in genes from the renin-angiotensin, bradykinin and fibrinolytic systems on plasma t-PA and PAI-1 levels in a large population-based sample (n=2,527). We demonstrated a strong significant interaction within genetic variations of the bradykinin B2 gene (p=0.002) and between ACE and bradykinin B2 (p=0.003) polymorphisms on t-PA levels in females. In males, polymorphisms in the bradykinin B2 and AT1R gene showed the most strong effect on t-PA levels (p=0.006). In both females as well as males, the bradykinin B2 gene interacted with AT1R gene on plasma PAI-1 levels (p=0.026 and p=0.039, respectively). In addition, the current study found a borderline significant interaction between PAI 4G5G and ACE I/D on plasma t-PA and PAI-1 levels. These results support the idea that the interplay between the renin-angiotensin, bradykinin, and fibrinolytic systems might play an important role in t-PA and PAI-1 biology. PMID:17207964

  17. Angiotensin receptor blockers are associated with lower mortality than ACE inhibitors in predialytic stage 5 chronic kidney disease: A nationwide study of therapy with renin-angiotensin system blockade.

    Directory of Open Access Journals (Sweden)

    Chih-Ching Lin

    Full Text Available Dual renin angiotensin system (RAS blockade using angiotensin-receptor blockers (ARBs in combination with angiotensin converting enzyme inhibitors (ACEIs is reported to improve proteinuria in both diabetic and non-diabetic patients. However, its renoprotective effect and safety remain uncertain in patients with advanced chronic kidney disease (CKD. From January 1, 2000 through June 30, 2009, we enrolled 14,117 pre-dialytic stage 5 CKD patients with serum creatinine >6mg/dL and hematocrit <28% under the treatment with erythropoiesis stimulating agents and RAS blockade. We used Cox proportional hazards regression models to estimate the hazard ratios (HRs against the commencement of long-term dialysis and all-cause mortality for ACEI/ARB users. Over a median follow-up of 7 months, 9,867 patients (69.9% required long-term dialysis and 2,805 (19.9% died before progression to end-stage renal disease requiring dialysis. In comparison with the ARB-only users, dual blockade with ACEIs and ARBs was associated with a significantly higher risk of (1 death in all CKD patients (HR = 1.49, [95%CI, 1.30-1.71]; P = 0.02 and in diabetic subgroup (HR = 1.58, [95%CI, 1.34-1.86]; P = 0.02; (2 composite endpoint of long-term dialysis or death in diabetic subgroup (HR = 1.10, [95%CI, 1.01-1.20]; P = 0.04; (3 hyperkalemia-associated hospitalization in non-diabetic subgroup (HR, 2.74, [95%CI, 1.05-7.15]; P = 0.04. However, ACEIs users were associated with higher mortality than ARBs users in all CKD patients (HR = 1.17, [95%CI, 1.07-1.27]; P = 0.03 and in diabetic subgroup (HR = 1.32, [95%CI, 1.18-1.48]; P = 0.03. Monotherapy of RAS blockade, especially ARB, is more effective and safer than dual RAS blockade in pre-dialytic stage 5 CKD patients.

  18. ROLE OF RENIN-ANGIOTENSIN SYSTEM AND OXIDATIVE STRESS AND INFLAMMATION TO THE BLOOD PRESSURE CONTROL IN YOUNG SUBJECTS

    Directory of Open Access Journals (Sweden)

    Emiko Sato

    2012-06-01

    Full Text Available Renin-Angiotensin System (RAS, oxidative stress and inflammation is involved in the pathogenesis of hypertension and salt sensitivity of hypertension. The present study was designed to evaluate the role of RAS, oxidative stress and inflammation to the regulation of blood pressure in young subjects. 111 young students (19.2±0.8 years old who have taken health checkup were randomly selected for the study. Urinary excretions of angiotensinogen (AGT, oxidative stress (TBARS, and inflammatory markers (MCP-1 were analyzed. Urinary excretions of these parameters were estimated by 24-hour urinary creatinine excretion, age, height and body weight. Subjects were divided to two groups based on the blood pressure: below 140/90 mmHg (Normal and over 140/90 mmHg (High. Blood pressure was significantly increased with increased BMI. Urinary AGT, TBARS, and MCP-1 of high blood pressure group were significantly (p<0.05 increased compared to those of normal blood pressure. Urinary AGT has significant positive correlation with urinary TBARS, though it did not have a significant correlation with MCP-1. Estimated 24-h urinary Na excretion was significantly increased with increased urinary MCP-1, and TBARS. These results indicate that increase in blood pressure is accompanied with RAS, oxidative stress, and inflammation in young subjects, which is associated with salt intake.

  19. Study of prognostic significance of antenatal ultrasonography and renin angiotensin system activation in predicting disease severity in posterior urethral valves

    Directory of Open Access Journals (Sweden)

    Divya Bhadoo

    2015-01-01

    Full Text Available Aims: Study on prognostic significance of antenatal ultrasonography and renin angiotensin system activation in predicting disease severity in posterior urethral valves. Materials and Methods: Antenatally diagnosed hydronephrosis patients were included. Postnatally, they were divided into two groups, posterior urethral valve (PUV and non-PUV. The studied parameters were: Gestational age at detection, surgical intervention, ultrasound findings, cord blood and follow up plasma renin activity (PRA values, vesico-ureteric reflux (VUR, renal scars, and glomerular filtration rate (GFR. Results: A total of 25 patients were included, 10 PUV and 15 non-PUV. All infants with PUV underwent primary valve incision. GFR was less than 60 ml/min/1.73 m 2 body surface area in 4 patients at last follow-up. Keyhole sign, oligoamnios, absent bladder cycling, and cortical cysts were not consistent findings on antenatal ultrasound in PUV. Cord blood PRA was significantly higher (P < 0.0001 in PUV compared to non-PUV patients. Gestational age at detection of hydronephrosis, cortical cysts, bladder wall thickness, and amniotic fluid index were not significantly correlated with GFR while PRA could differentiate between poor and better prognosis cases with PUV. Conclusions: Ultrasound was neither uniformly useful in diagnosing PUV antenatally, nor differentiating it from cases with non-PUV hydronephrosis. In congenital hydronephrosis, cord blood PRA was significantly higher in cases with PUV compared to non-PUV cases and fell significantly after valve ablation. Cord blood PRA could distinguish between poor and better prognosis cases with PUV.

  20. Renal Kallikrein Activation and Renoprotection after Dual Blockade of Renin-Angiotensin System in Diet-Induced Diabetic Nephropathy

    Science.gov (United States)

    Zou, Xia; Zhang, Xiao-xi; Liu, Xin-yu; Li, Rong; Wang, Min; Wu, Wei-jie; Sui, Yi; Zhao, Hai-lu

    2015-01-01

    Purpose. The objective of this study is to investigate the effect of dual blockage of renin-angiotensin system (RAS) on renal kallikrein expression and inflammatory response in diabetic nephropathy (DN). Methods. Rats were randomly divided into 5 groups with 10 rats in each group: normal control; DN model induced by high fat and high sucrose diets; and DN treated with either benazepril 10 mg/kg/d, irbesartan 30 mg/kg/d, or both. After 8-week treatment, we examined changes in the kidney histopathology, function and immunohistochemical stain of kallikrein, macrophage marker CD68, and profibrotic markers transforming growth factor- (TGF-) β and α-smooth muscle action (SMA). Results. DN rats showed enlarged kidneys with glomerulosclerosis, interstitial chronic inflammation and fibrosis, and proteinuria. All the pathological damage and functional impairments were improved after the RAS blockades (all P < 0.05). Compared with monotherapy, combined treatment further alleviated the kidney impairments in parallel to increased tubular immunoreactivity for kallikrein and decreased immunopositive cells for CD68, TGF-β, and α-SMA. Conclusion. The renoprotective effects of the dual RAS blockade in diabetic nephropathy may be attributed to improved tubular kallikrein expression and interstitial inflammatory response. PMID:25918729

  1. [Cardiovascular risk study in patients with renin-angiotensin system blockade by means of the proteone of circulating extracellular vesicles].

    Science.gov (United States)

    de la Cuesta, F; Baldan-Martin, M; Mourino-Alvarez, L; Sastre-Oliva, T; Alvarez-Llamas, G; Gonzalez-Calero, L; Ruiz-Hurtado, G; Segura, J; Vivanco, F; Ruilope, L M; Barderas, M G

    2016-01-01

    Extracellular vesicles (EVs) are released to the bloodstream by certain cell types due to transport, activation and cell death processes. Blood count of EVs from platelet and endothelial origin has been proved to be a cardiovascular risk biomarker. Thus, EVs proteome might reflect the underlying cellular processes in hypertensive patients with albuminuria. Protein content of circulating EVs was analyzed by liquid chromatography coupled to mass spectrometry. EVs were isolated by an ultracentrifugation protocol optimized in order to avoid contamination by blood plasma proteins. Purity of the isolated fraction was verified by electronic and confocal microscopy, and by flow cytometry. We hereby show a method to isolate circulating EVs from hypertensive patients with/without albuminuria with high yield and purity. Besides, we provide a reference proteome of the EVs of these patients, composed of 2,463 proteins, and prove that the proteins carried by these vesicles are associated with crucial processes involved in the inherent cardiovascular risk. The proteome of circulating EVs is an interesting source of indicators in the evaluation of cardiovascular risk in hypertensive patients with renin-angiotensin system blockage. Copyright © 2015 SEHLELHA. Published by Elsevier España, S.L.U. All rights reserved.

  2. Angiotensin converting enzyme-independent, local angiotensin II-generation in human pancreatic ductal cancer tissues.

    Science.gov (United States)

    Ohta, Tetsuo; Amaya, Kohji; Yi, Shuangqin; Kitagawa, Hirohisa; Kayahara, Masato; Ninomiya, Itasu; Fushida, Sachio; Fujimura, Takashi; Nishimura, Gen-Ichi; Shimizu, Koichi; Miwa, Koichi

    2003-09-01

    Hypovascularity is an outstanding characteristic of pancreatic ductal cancer by diagnostic imaging: most pancreatic ductal cancers are hypovascular or avascular, and tumor vessels are seldom seen on angiography. However, we found that the vasculature was not always poor on angiography of surgically resected specimens of locally advanced pancreatic ductal cancers. To elucidate these controversial findings, we focused on angiotensin II, a vasoconstrictor which is directly produced from angiotensinogen at acidic pH by active trypsin. We examined whether a local angiotensin II-generating system exists in pancreatic ductal cancer tissue. We measured angiotensin II concentration and angiotensin converting enzyme (ACE) activity in tissues from normal pancreas, pancreatic ductal cancers, colon cancers, and hepatocellular carcinomas. After surgically resected specimens were homogenized, angiotensin II concentration and ACE activity in tissues were measured using the florisil method and the Kasahara method, respectively. Tissue angiotensin II levels in pancreatic ductal cancer (n=13) were significantly higher than those of normal pancreas (n=7), colon cancers (n=7), or hepatocellular carcinomas (n=7). However, there was no significant difference in the ACE activity in tissue between them. This study provides in vivo evidence of an ACE-independent, angiotensin II-generating system in pancreatic ductal cancer tissues and suggests that locally formed angiotensin II may act on the pre-existing pancreatic arteries around the tumor, leading to formation of hypovascular or avascular regions.

  3. Angiotensin II during Experimentally Simulated Central Hypovolemia

    DEFF Research Database (Denmark)

    Jensen, Theo Walther; Olsen, Niels Vidiendal

    2016-01-01

    of angiotensin II during episodes of central hypovolemia. To examine this, we reviewed results from studies with three experimental models of simulated hypovolemia: head up tilt table test, lower body negative pressure, and hemorrhage of animals. A systemic literature search was made with the use of Pub......Med/MEDLINE for studies that measured variables of the renin-angiotensin system or its effect during simulated hypovolemia. Twelve articles, using one of the three models, were included and showed a possible organ-protective effect and an effect on the sympathetic system of angiotensin II during hypovolemia. The results...... of these agents in a hypovolemic setting. We argue that the latest debates on the effect of angiotensin II during hypovolemia might guide for future studies, investigating the effect of such agents during experimentally simulated central hypovolemia. The purpose of this review is to examine the role...

  4. Active renin mass concentration to determine aldosterone-to-renin ratio in screening for primary aldosteronism

    Directory of Open Access Journals (Sweden)

    Corbin F

    2011-07-01

    Full Text Available François Corbin1, Pierre Douville2, Marcel Lebel3 1Division of Biochemistry, l'Université de Sherbrooke, Sherbrooke, Quebec, Canada; 2Division of Biochemistry; 3Division of Nephrology, L'Hôtel-Dieu de Québec Hospital and l'Université Laval, Quebec, CanadaBackground: Active renin mass concentration (ARC is independent of the endogenous level of angiotensinogen, and less variable and more reproducible than plasma renin activity. Reference values for the aldosterone-to-renin ratio (ARR using ARC are still undefined. The objective of the present study was to determine the threshold of ARR using ARC measurement to screen for primary aldosteronism.Methods: A total of 211 subjects were included in the study, comprising 78 healthy normotensive controls, 95 patients with essential hypertension, and 38 patients with confirmed primary aldosteronism (20 with surgery-confirmed aldosterone-producing adenoma and 18 with idiopathic adrenal hyperplasia. Blood samples were drawn from ambulatory patients and volunteers in the mid-morning without specific dietary restriction for measuring plasma aldosterone concentration, ARC, and serum potassium.Results: Most normotensive controls and essential hypertension patients had ARR results below 100 pmol/ng, a value which corresponded to 3.3 times the median of these two groups.Conclusion: Patients with ARR values above this level should be considered for further investigation (confirmatory tests or for repeat testing should ARR values be borderline. This study indicates that ARC can be used reliably in determining ARR for primary aldosteronism screening.Keywords: primary aldosteronism, active renin mass concentration, aldosterone-to-renin ratio

  5. Sildenafil Protects against Myocardial Ischemia-Reperfusion Injury Following Cardiac Arrest in a Porcine Model: Possible Role of the Renin-Angiotensin System

    Science.gov (United States)

    Wang, Guoxing; Zhang, Qian; Yuan, Wei; Wu, Junyuan; Li, Chunsheng

    2015-01-01

    Sildenafil, a phosphodiesterase-5 inhibitor sold as Viagra, is a cardioprotector against myocardial ischemia/reperfusion (I/R) injury. Our study explored whether sildenafil protects against I/R-induced damage in a porcine cardiac arrest and resuscitation (CAR) model via modulating the renin-angiotensin system. Male pigs were randomly divided to three groups: Sham group, Saline group, and sildenafil (0.5 mg/kg) group. Thirty min after drug infusion, ventricular fibrillation (8 min) and cardiopulmonary resuscitation (up to 30 min) was conducted in these animals. We found that sildenafil ameliorated the reduced cardiac function and improved the 24-h survival rate in this model. Sildenafil partly attenuated the increases of plasma angiotensin II (Ang II) and Ang (1–7) levels after CAR. Sildenafil also decreased apoptosis and Ang II expression in myocardium. The increases of expression of angiotensin-converting-enzyme (ACE), ACE2, Ang II type 1 receptor (AT1R), and the Ang (1–7) receptor Mas in myocardial tissue were enhanced after CAR. Sildenafil suppressed AT1R up-regulation, but had no effect on ACE, ACE2, and Mas expression. Sildenafilfurther boosted the upregulation of endothelial nitric oxide synthase (eNOS), cyclic guanosine monophosphate (cGMP) and inducible nitric oxide synthase(iNOS). Collectively, our results suggest that cardioprotection of sildenafil in CAR model is accompanied by an inhibition of Ang II-AT1R axis activation. PMID:26569234

  6. Sildenafil Protects against Myocardial Ischemia-Reperfusion Injury Following Cardiac Arrest in a Porcine Model: Possible Role of the Renin-Angiotensin System

    Directory of Open Access Journals (Sweden)

    Guoxing Wang

    2015-11-01

    Full Text Available Sildenafil, a phosphodiesterase-5 inhibitor sold as Viagra, is a cardioprotector against myocardial ischemia/reperfusion (I/R injury. Our study explored whether sildenafil protects against I/R-induced damage in a porcine cardiac arrest and resuscitation (CAR model via modulating the renin-angiotensin system. Male pigs were randomly divided to three groups: Sham group, Saline group, and sildenafil (0.5 mg/kg group. Thirty min after drug infusion, ventricular fibrillation (8 min and cardiopulmonary resuscitation (up to 30 min was conducted in these animals. We found that sildenafil ameliorated the reduced cardiac function and improved the 24-h survival rate in this model. Sildenafil partly attenuated the increases of plasma angiotensin II (Ang II and Ang (1–7 levels after CAR. Sildenafil also decreased apoptosis and Ang II expression in myocardium. The increases of expression of angiotensin-converting-enzyme (ACE, ACE2, Ang II type 1 receptor (AT1R, and the Ang (1–7 receptor Mas in myocardial tissue were enhanced after CAR. Sildenafil suppressed AT1R up-regulation, but had no effect on ACE, ACE2, and Mas expression. Sildenafilfurther boosted the upregulation of endothelial nitric oxide synthase (eNOS, cyclic guanosine monophosphate (cGMP and inducible nitric oxide synthase(iNOS. Collectively, our results suggest that cardioprotection of sildenafil in CAR model is accompanied by an inhibition of Ang II-AT1R axis activation.

  7. Angiotensin 2 directly increases rabbit renal brush-border membrane sodium transport: Presence of local signal transduction system

    Energy Technology Data Exchange (ETDEWEB)

    Morduchowicz, G.A.; Sheikh-Hamad, D.; Dwyer, B.E.; Stern, N.; Jo, O.D.; Yanagawa, N. (Sepulveda Veterans Administration, CA (USA))

    1991-05-01

    In the present study, the authors have examined the direct actions of angiotensin II (AII) in rabbit renal brush border membrane (BBM) where binding sites for AII exist. Addition of AII (10(-11)-10(-7) M) was found to stimulate 22Na+ uptake by the isolated BBM vesicles directly. All did not affect the Na(+)-dependent BBM glucose uptake, and the effect of AII on BBM 22Na+ uptake was inhibited by amiloride, suggesting the involvement of Na+/H+ exchange mechanism. BBM proton permeability as assessed by acridine orange quenching was not affected by AII, indicating the direct effect of AII on Na+/H+ antiport system. In search of the signal transduction mechanism, it was found that AII activated BBM phospholipase A2 (PLA) and that BBM contains a 42-kDa guanine nucleotide-binding regulatory protein (G-protein) that underwent pertussis toxin (PTX)-catalyzed ADP-ribosylation. Addition of GTP potentiated, while GDP-beta S or PTX abolished, the effects of AII on BBM PLA and 22Na+ uptake, suggesting the involvement of G-protein in AII's actions. On the other hand, inhibition of PLA by mepacrine prevented AII's effect on BBM 22Na+ uptake, and activation of PLA by mellitin or addition of arachidonic acid similarly enhanced BBM 22Na+ uptake, suggesting the role of PLA activation in mediating AII's effect on BBM 22Na+ uptake. In summary, results of the present study show a direct stimulatory effect of AII on BBM Na+/H+ antiport system, and suggest the presence of a local signal transduction system involving G-protein mediated PLA activation.

  8. Reporter mouse strain provides a novel look at angiotensin type-2 receptor distribution in the central nervous system

    DEFF Research Database (Denmark)

    de Kloet, Annette D; Wang, Lei; Ludin, Jacob A

    2016-01-01

    Angiotensin-II acts at its type-1 receptor (AT1R) in the brain to regulate body fluid homeostasis, sympathetic outflow and blood pressure. However, the role of the angiotensin type-2 receptor (AT2R) in the neural control of these processes has received far less attention, largely because of limited...... ability to effectively localize these receptors at a cellular level in the brain. The present studies combine the use of a bacterial artificial chromosome transgenic AT2R-enhanced green fluorescent protein (eGFP) reporter mouse with recent advances in in situ hybridization (ISH) to circumvent...

  9. [The in vitro cross-effects of inhibitors of renin-angiotensin and fibrinolytic systems on the key enzymes of these systems].

    Science.gov (United States)

    Mukhametova, L I; Gulin, D A; Binevskiĭ, P V; Aĭsina, R B; Kost, O A; Nikol'skaia, I I

    2008-01-01

    The effects of hypotensive agents (captopril, enalaprilate, and lisinopril) on the activities of components of the fibrinolytic system (FS) and the effects of antifibrinolytic agents (6-aminohexanoic acid (6-AHA) and tranexamic acid (t-AMCHA)) on the activities of angiotensin converting enzyme (ACE) were studied in vitro. Enalaprilate did not affect the FS activity. Captopril considerably inhibited the amidase activities of urokinase (u-PA), plasminogen tissue activator (t-PA), and plasmin ([I]50 (2.0-2.6) +/- 0.1 mM), and the activation of Glu-plasminogen affected by t-PA and u-PA ([I]50 (1.50-1.80) +/- 0.06 mM), which may be due to the presence of a mercapto group in the inhibitor molecule. Lisinopril did not affect the amidase activities of FS enzymes, but stimulated Glu-plasminogen and u-PA activation and inhibited activation of t-PA-fibrin-bound Glu-plasminogen ([I]50 (12.0 +/- 0.5) mM). Presumably, these effects can be explained by the presence in lisinopril of a Lys side residue, whose binding to lysine-binding Glu-plasminogen centers resulted, on the one hand, in the transformation of its closed conformation to a semi-open one and, on the other hand, in its desorption from fibrin. Unspecific inhibition of the activity of ACE, a key enzyme of the renin-angiotensin system, in the presence of 6-AHA and t-AMCHA ([I]50 10.0 +/- 0.5 and 7.5 +/- 0.4 mM, respectively) was found. A decrease in the ACE activity along with the growth of the fibrin monomer concentration was revealed. The data demonstrate that, along with endogenous mediated interactions, relations based on the direct interactions of exogenous inhibitors of one system affecting the activities of components of another system can take place.

  10. Impact of Angiotensin Type 1A Receptors in Principal Cells of the Collecting Duct on Blood Pressure and Hypertension.

    Science.gov (United States)

    Chen, Daian; Stegbauer, Johannes; Sparks, Matthew A; Kohan, Donald; Griffiths, Robert; Herrera, Marcela; Gurley, Susan B; Coffman, Thomas M

    2016-06-01

    The main actions of the renin-angiotensin system to control blood pressure (BP) are mediated by the angiotensin type 1 receptors (AT1Rs). The major murine AT1R isoform, AT1AR, is expressed throughout the nephron, including the collecting duct in both principal and intercalated cells. Principal cells play the major role in sodium and water reabsorption. Although aldosterone is considered to be the dominant regulator of sodium reabsorption by principal cells, recent studies suggest a role for direct actions of AT1R. To specifically examine the contributions of AT1AR in principal cells to BP regulation and the development of hypertension in vivo, we generated inbred 129/SvEv mice with deletion of AT1AR from principal cells (PCKO). At baseline, we found that BPs measured by radiotelemetry were similar between PCKOs and controls. During 1-week of low-salt diet (hypertension, there was a modest but significant attenuation of hypertension in PCKOs (163±6 mm Hg) compared with controls (178±2 mm Hg; Phypertension and epithelial sodium channel activation. © 2016 American Heart Association, Inc.

  11. The effect of oxygen on aldosterone release from bovine adrenocortical cells in vitro: PO2 versus steroidogenesis.

    Science.gov (United States)

    Raff, H; Kohandarvish, S

    1990-08-01

    Hypoxia decreases plasma aldosterone in vivo without a decrease in PRA, angiotensin II (ANG II), ACTH, or cortisol. The present study evaluated whether this could be due to a direct, specific inhibitory effect on the zona glomerulosa related to the magnitude of the decrease in oxygen (O2). Bovine adrenocortical cells were dispersed with collagenase and studied in vitro within 48 h. Cells were stimulated for 2 h with ANG II (0.1-1000 nM) or (Bu)2cAMP (0.3-3 mM) under oxygen levels ranging from 0 to 100% O2 (PO2 from 66 +/- 4 to 561 +/- 46 torr) vs. a reference gas mixture (21% O2 PO2 approximately 140 torr). Exposure to 123 +/- 8, 110 +/- 12, 100 +/- 16, and 66 +/- 4 torr led to 27%, 30%, 40% and 70% inhibition, respectively, of 3 nM ANG II-stimulated aldosterone secretion as compared to 140 +/- 16 torr (reference). Exposure to hyperoxia (288 +/- 36 to 561 +/- 46 torr) led to a small (10%) increase in ANG II-stimulated aldosterone secretion which was not statistically significant. The P50 (half-maximal PO2) for aldosteronogenesis was approximately 95 torr. The results for other doses of ANG II and for cAMP were similar. The inhibitory effect of low O2 was reversed by returning the cells to reference conditions (140 +/- 16 torr). Cortisol secretion was not significantly affected by changes in oxygen tension. We conclude that small changes in O2 within the physiological range directly and specifically inhibit aldosteronogenesis in a dose-dependent manner with a P50 of approximately 95 torr. Inhibition of cAMP-stimulated aldosterone secretion suggests a postreceptor site of action. This direct, reversible, and specific effect on the zona glomerulosa of the adrenal cortex may account for the dissociation of renin and aldosterone during hypoxia in vivo.

  12. Targeting of captopril to the kidney reduces renal angiotensin-converting enzyme activity without affecting systemic blood pressure

    NARCIS (Netherlands)

    Kok, RJ; Haverdings, Rene; Grijpstra, F; Koiter, J.; Moolenaar, F; De Zeeuw, D; Meijer, DKF

    We have synthesized a prodrug of the angiotensin-converting enzyme (ACE) inhibitor captopril by coupling this drug covalently to the low molecular weight protein (LMWP) lysozyme. Such drug-LMWP conjugates can be used for renal drug delivery, since LMWPs accumulate specifically in the proximal

  13. Targeting the Renin–Angiotensin System Combined With an Antioxidant Is Highly Effective in Mitigating Radiation-Induced Lung Damage

    Energy Technology Data Exchange (ETDEWEB)

    Mahmood, Javed [Ontario Cancer Institute and the Campbell Family Institute for Cancer Research, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario (Canada); Radiation Medicine Program, STTARR Innovation Centre, Princess Margaret Cancer Centre, Toronto, Ontario (Canada); Jelveh, Salomeh [Radiation Medicine Program, STTARR Innovation Centre, Princess Margaret Cancer Centre, Toronto, Ontario (Canada); Zaidi, Asif [Ontario Cancer Institute and the Campbell Family Institute for Cancer Research, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario (Canada); Doctrow, Susan R. [Pulmonary Center, Department of Medicine, Boston University, Boston, Massachusetts (United States); Medhora, Meetha [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Hill, Richard P., E-mail: hill@uhnres.utoronto.ca [Ontario Cancer Institute and the Campbell Family Institute for Cancer Research, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario (Canada); Departments of Medical Biophysics and Radiation Oncology, University of Toronto, Toronto, Ontario (Canada)

    2014-07-15

    Purpose: To investigate the outcome of suppression of the renin angiotensin system using captopril combined with an antioxidant (Eukarion [EUK]-207) for mitigation of radiation-induced lung damage in rats. Methods and Materials: The thoracic cavity of female Sprague-Dawley rats was irradiated with a single dose of 11 Gy. Treatment with captopril at a dose of 40 mg/kg/d in drinking water and EUK-207 given by subcutaneous injection (8 mg/kg daily) was started 1 week after irradiation (PI) and continuing until 14 weeks PI. Breathing rate was monitored until the rats were killed at 32 weeks PI, when lung fibrosis was assessed by lung hydroxyproline content. Lung levels of the cytokine transforming growth factor-β1 and macrophage activation were analyzed by immunohistochemistry. Oxidative DNA damage was assessed by 8-hydroxy-2-deoxyguanosine levels, and lipid peroxidation was measured by a T-BARS assay. Results: The increase in breathing rate in the irradiated rats was significantly reduced by the drug treatments. The drug treatment also significantly decreased the hydroxyproline content, 8-hydroxy-2-deoxyguanosine and malondialdehyde levels, and levels of activated macrophages and the cytokine transforming growth factor-β1 at 32 weeks. Almost complete mitigation of these radiation effects was observed by combining captopril and EUK-207. Conclusion: Captopril and EUK-207 can provide mitigation of radiation-induced lung damage out to at least 32 weeks PI after treatment given 1-14 weeks PI. Overall the combination of captopril and EUK-207 was more effective than the individual drugs used alone.

  14. Renin-angiotensin system blockers protect pancreatic islets against diet-induced obesity and insulin resistance in mice.

    Directory of Open Access Journals (Sweden)

    Eliete Dalla Corte Frantz

    Full Text Available BACKGROUND: The associations between obesity, hypertension and diabetes are well established, and the renin-angiotensin system (RAS may provide a link among them. The effect of RAS inhibition on type 2 diabetes is still unclear; however, RAS seems to play an important role in the regulation of the pancreas and glucose intolerance of mice fed high-fat (HF diet. METHODS: C57BL/6 mice fed a HF diet (8 weeks were treated with aliskiren (50 mg/kg/day, enalapril (30 mg/kg/day or losartan (10 mg/kg/day for 6 weeks, and the protective effects were extensively compared among groups by morphometry, stereological tools, immunostaining, Western blotting and hormonal analysis. RESULTS: All RAS inhibitors significantly attenuated the increased blood pressure in mice fed a HF diet. Treatment with enalapril, but not aliskiren or losartan, significantly attenuated body mass (BM gain, glucose intolerance and insulin resistance, improved the alpha and beta cell mass and prevented the reduction of plasma adiponectin. Furthermore, enalapril treatment improved the protein expression of the pancreatic islet Pdx1, GLUT2, ACE2 and Mas receptors. Losartan treatment showed the greatest AT2R expression. CONCLUSION: Our findings indicate that ACE inhibition with enalapril attenuated several of the deleterious effects of the HF diet. In summary, enalapril appears to be responsible for the normalization of islet morphology and function, of alpha and beta cell mass and of Pdx1 and GLUT2 expression. These protective effects of enalapril were attributed, primarily, to the reduction in body mass gain and food intake and the enhancement of the ACE2/Ang (1-7 /Mas receptor axis and adiponectin levels.

  15. Common variants of the beta and gamma subunits of the epithelial sodium channel and their relation to plasma renin and aldosterone levels in essential hypertension

    Directory of Open Access Journals (Sweden)

    Krusius Tom

    2005-01-01

    Full Text Available Abstract Background Rare mutations of the epithelial sodium channel (ENaC result in the monogenic hypertension form of Liddle's syndrome. We decided to screen for common variants in the ENaC βand γ subunits in patients with essential hypertension and to relate their occurrence to the activity of circulating renin-angiotensin-aldosterone system. Methods Initially, DNA samples from 27 patients with low renin/low aldosterone hypertension were examined. The DNA variants were subsequently screened for in 347 patients with treatment-resistant hypertension, 175 male subjects with documented long-lasting normotension and 301 healthy Plasma renin and aldosterone levels were measured under baseline conditions and during postural and captopril challenge tests. Results Two commonly occurring βENaC variants (G589S and a novel intronic i12-17CT substitution and one novel γENaC variant (V546I were detected. One of these variants occurred in a heterozygous form in 32 patients, a prevalence (9.2% significantly higher than that in normotensive males (2.9%, p = 0.007 and blood donors (3.0%, p = 0.001. βENaC i12-17CT was significantly more prevalent in the hypertension group than in the two control groups combined (4.6% vs. 1.1%, p = 0.001. When expressed in Xenopus oocytes, neither of the two ENaC amino acid-changing variants showed a significant difference in activity compared with ENaC wild-type. No direct evidence for a mRNA splicing defect could be obtained for the βENaC intronic variant. The ratio of daily urinary potassium excretion to upright and mean (of supine and upright values plasma renin activity was higher in variant allele carriers than in non-carriers (p = 0.034 and p = 0.048. Conclusions At least 9% of Finnish patients with hypertension admitted to a specialized center carry genetic variants of β and γENaC, a three times higher prevalence than in the normotensive individuals or in random healthy controls. Patients with the variant alleles

  16. The Occurrence of Apparent Bilateral Aldosterone Suppression in Adrenal Vein Sampling for Primary Aldosteronism.

    Science.gov (United States)

    Shibayama, Yui; Wada, Norio; Naruse, Mitsuhide; Kurihara, Isao; Ito, Hiroshi; Yoneda, Takashi; Takeda, Yoshiyu; Umakoshi, Hironobu; Tsuiki, Mika; Ichijo, Takamasa; Fukuda, Hisashi; Katabami, Takuyuki; Yoshimoto, Takanobu; Ogawa, Yoshihiro; Kawashima, Junji; Ohno, Yuichi; Sone, Masakatsu; Fujita, Megumi; Takahashi, Katsutoshi; Shibata, Hirotaka; Kamemura, Kohei; Fujii, Yuichi; Yamamoto, Koichi; Suzuki, Tomoko

    2018-05-01

    In adrenal venous sampling (AVS) for patients with primary aldosteronism (PA), apparent bilateral aldosterone suppression (ABAS), defined as lower aldosterone/cortisol ratios in the bilateral adrenal veins than that in the inferior vena cava, is occasionally experienced. ABAS is uninterpretable with respect to lateralization of excess aldosterone production. We previously reported that ABAS was not a rare phenomenon and was significantly reduced after adrenocorticotropic hormone (ACTH) administration. To validate the effects of ACTH administration and adding sampling positions in the left adrenal vein on the prevalence of ABAS in the larger Japan Primary Aldosteronism Study. The data from 1689 patients with PA who underwent AVS between January 2006 and October 2016 were studied. All patients in the previous study, the West Japan Adrenal Vein Sampling study, were excluded. The prevalence of ABAS was investigated at two sampling positions in the left adrenal vein, the central vein and the common trunk, without and with ACTH administration. The prevalence of ABAS with ACTH administration was significantly lower than that without ACTH administration [without ACTH vs with ACTH: 79/440 (18.0%) vs 45/591 (7.6%); P sampling position, at the central vein and at the common trunk [33/591 (5.6%) vs 32/591 (5.4%); P = 1.00]. The effectiveness of ACTH administration for the reduction of ABAS in AVS regardless of the sampling position in the left adrenal vein was confirmed in the larger cohort.

  17. Polyphenol-Rich Blackcurrant Juice Prevents Endothelial Dysfunction in the Mesenteric Artery of Cirrhotic Rats with Portal Hypertension: Role of Oxidative Stress and the Angiotensin System.

    Science.gov (United States)

    Rashid, Sherzad; Idris-Khodja, Noureddine; Auger, Cyril; Kevers, Claire; Pincemail, Joël; Alhosin, Mahmoud; Boehm, Nelly; Oswald-Mammosser, Monique; Schini-Kerth, Valérie B

    2018-04-01

    Chronic liver diseases with portal hypertension are characterized by a progressive vasodilatation, endothelial dysfunction, and NADPH oxidase-derived vascular oxidative stress, which have been suggested to involve the angiotensin system. This study evaluated the possibility that oral intake of polyphenol-rich blackcurrant juice (PRBJ), a rich natural source of antioxidants, prevents endothelial dysfunction in a rat model of cirrhosis induced by chronic bile duct ligation (CBDL), and, if so, determined the underlying mechanism. Male Wistar rats received either control drinking water or water containing 60 mg/kg gallic acid equivalents of PRBJ for 3 weeks before undergoing surgery with CBDL or sham surgery. After 4 weeks, vascular reactivity was assessed in mesenteric artery rings using organ chambers. Both the acetylcholine-induced nitric oxide (NO)- and endothelium-dependent hyperpolarization (EDH)-mediated relaxations in mesenteric artery rings were significantly reduced in CBDL rats compared to sham rats. An increased level of oxidative stress and expression of NADPH oxidase subunits, COX-2, NOS, and of the vascular angiotensin system are observed in arterial sections in the CBDL group. Chronic intake of PRBJ prevented the CBDL-induced impaired EDH-mediated relaxation, oxidative stress, and expression of the different target proteins in the arterial wall. In addition, PRBJ prevented the CBDL-induced increase in the plasma level of proinflammatory cytokines (interleukin [IL]-1α, monocyte chemotactic protein 1, and tumor necrosis factor α) and the decrease of the anti-inflammatory cytokine, IL-4. Altogether, these observations indicate that regular ingestion of PRBJ prevents the CBDL-induced endothelial dysfunction in the mesenteric artery most likely by normalizing the level of vascular oxidative stress and the angiotensin system.

  18. Overexpression of the neuronal human (pro)renin receptor mediates angiotensin II-independent blood pressure regulation in the central nervous system.

    Science.gov (United States)

    Peng, Hua; Jensen, Dane D; Li, Wencheng; Sullivan, Michelle N; Buller, Sophie A; Worker, Caleb J; Cooper, Silvana G; Zheng, Shiqi; Earley, Scott; Sigmund, Curt D; Feng, Yumei

    2018-03-01

    Despite advances in antihypertensive therapeutics, at least 15-20% of hypertensive patients have resistant hypertension through mechanisms that remain poorly understood. In this study, we provide a new mechanism for the regulation of blood pressure (BP) in the central nervous system (CNS) by the (pro)renin receptor (PRR), a recently identified component of the renin-angiotensin system that mediates ANG II formation in the CNS. Although PRR also mediates ANG II-independent signaling, the importance of these pathways in BP regulation is unknown. Here, we developed a unique transgenic mouse model overexpressing human PRR (hPRR) specifically in neurons (Syn-hPRR). Intracerebroventricular infusion of human prorenin caused increased BP in Syn-hPRR mice. This BP response was attenuated by a NADPH oxidase (NOX) inhibitor but not by antihypertensive agents that target the renin-angiotensin system. Using a brain-targeted genetic knockdown approach, we found that NOX4 was the key isoform responsible for the prorenin-induced elevation of BP in Syn-hPRR mice. Moreover, inhibition of ERK significantly attenuated the increase in NOX activity and BP induced by human prorenin. Collectively, our findings indicate that an ANG II-independent, PRR-mediated signaling pathway regulates BP in the CNS by a PRR-ERK-NOX4 mechanism. NEW & NOTEWORTHY This study characterizes a new transgenic mouse model with overexpression of the human (pro)renin receptor in neurons and demonstrated a novel angiotensin II-independent mechanism mediated by human prorenin and the (pro)renin receptor in the central regulation of blood pressure.

  19. Aldosterone and the heart: still an unresolved issue?

    Directory of Open Access Journals (Sweden)

    Cristiana eCatena

    2014-10-01

    Full Text Available Receptors for mineralocorticoid hormones are expressed in myocardial cells and evidence obtained in animal studies suggests that activation of these receptors causes cardiac damage independent from blood pressure levels. In the last years, many of the issues related to the effects of aldosterone on the heart have received convincing answers and clinical investigation has focused on a variety of conditions including systolic and diastolic heart failure, arrhythmia, primary hypertension, and primary aldosteronism. Some issues, however, await clarification in order to obtain better understanding of what could be the role of aldosterone blockade in prevention and treatment of cardiovascular diseases. In this article, we overview the most recent findings of animal studies that have examined the contribution of aldosterone to cardiac function and clinical studies that have investigated the influence of aldosterone on left ventricular structure and function in the setting of primary hypertension and primary aldosteronism.

  20. Mechanisms underlying rapid aldosterone effects in the kidney.

    LENUS (Irish Health Repository)

    Thomas, Warren

    2012-02-01

    The steroid hormone aldosterone is a key regulator of electrolyte transport in the kidney and contributes to both homeostatic whole-body electrolyte balance and the development of renal and cardiovascular pathologies. Aldosterone exerts its action principally through the mineralocorticoid receptor (MR), which acts as a ligand-dependent transcription factor in target tissues. Aldosterone also stimulates the activation of protein kinases and secondary messenger signaling cascades that act independently on specific molecular targets in the cell membrane and also modulate the transcriptional action of aldosterone through MR. This review describes current knowledge regarding the mechanisms and targets of rapid aldosterone action in the nephron and how aldosterone integrates these responses into the regulation of renal physiology.

  1. Mechanisms underlying rapid aldosterone effects in the kidney.

    LENUS (Irish Health Repository)

    Thomas, Warren

    2011-03-17

    The steroid hormone aldosterone is a key regulator of electrolyte transport in the kidney and contributes to both homeostatic whole-body electrolyte balance and the development of renal and cardiovascular pathologies. Aldosterone exerts its action principally through the mineralocorticoid receptor (MR), which acts as a ligand-dependent transcription factor in target tissues. Aldosterone also stimulates the activation of protein kinases and secondary messenger signaling cascades that act independently on specific molecular targets in the cell membrane and also modulate the transcriptional action of aldosterone through MR. This review describes current knowledge regarding the mechanisms and targets of rapid aldosterone action in the nephron and how aldosterone integrates these responses into the regulation of renal physiology.

  2. Radioimmunoassay of aldosterone and its level in plasma and urine

    International Nuclear Information System (INIS)

    Putz, Z.; Hampl, R.; Veleminsky, J.; Starka, L.

    1981-01-01

    A method of plasma and urine aldosterone radioimmunoassay is described and evaluated. Highly specific antisera were obtained through rabbit immunization using partly aldosterone-18,21-dihemisuccinate-BSA, partly aldosterone-3-carboxymethyl-oxime-BSA, free of the 18-derivative. The use of a more specific antiserum against the 3-derivative permitted the determination to be performed immediately from the biological specimen extract. Hydrolysis with sulphuric acid in the presence of dichloromethane proved the most appropriate of the different techniques of releasing aldosterone-glucuronoside for the determination of the total urine hormone. The normal values (average +- 2 S. D.) of plasma aldosterone were 0.19 +- 0.067 nmol/l, those of the free urine hormone 0.918 +- 0.458 nmol/day, and the total urine aldosterone 15.3 +- 5.8 nmol/day. (author)

  3. Predictors of malignancy in primary aldosteronism.

    Science.gov (United States)

    Agha, Ayman; Hornung, Matthias; Iesalnieks, Igors; Schreyer, Andreas; Jung, Ernst Michael; Haneya, Assad; Schlitt, Hans J

    2014-01-01

    Primary aldosteronism (PA, also Conn syndrome) is a benign disease in majority of cases. However, malignant transformation has been described. Present study reports on three cases of aldosterone producing adrenocortical carcinoma (APAC) in comparison to patients with benign PA. Data of patients undergoing adrenalectomy for benign PA were compared to patients with APAC. Retrospective chart analysis was performed. All patients received spironolactone for 6-8 weeks preoperatively. Seventy-four patients underwent adrenalectomy for PA between 1994 and 2011. Three of them revealed an APAC. Patients with APAC presented with a significantly lower serum potassium level (1.7 mmol/l vs. 3.4 mmol/l, p = 0.001) and significant larger tumors (5.2 vs. 1.8 cm, p = 0.002). In addition, aldosterone/renin (A/R) ratio 675 in patients with APAC as compared to 74 in patients with benign PA (p = 0.0001). Sixty-eight of 71 patients with benign PA underwent minimal invasive surgery, whereas all three patients with APAC were operated conventionally. All patients with APAC developed disease recurrence 6-18 months postoperatively. Tumor size >4 cm and a very high A/R ratio seems to predictors of malignancy in patients with PA. If these criteria are present, open adrenalectomy should be performed instead of endoscopic procedure.

  4. Stress-induced Aldosterone Hyper-Secretion in a Substantial Subset of Patients With Essential Hypertension.

    Science.gov (United States)

    Markou, Athina; Sertedaki, Amalia; Kaltsas, Gregory; Androulakis, Ioannis I; Marakaki, Chrisanthi; Pappa, Theodora; Gouli, Aggeliki; Papanastasiou, Labrini; Fountoulakis, Stelios; Zacharoulis, Achilles; Karavidas, Apostolos; Ragkou, Despoina; Charmandari, Evangelia; Chrousos, George P; Piaditis, George P

    2015-08-01

    Aldosterone (ALD) secretion is regulated mainly by angiotensin II, K(+), and adrenocorticotropic hormone (ACTH). Mineralocorticoid receptor antagonists (MRAs) have effectively been used for the treatment of patients with hypertension who do not have primary aldosteronism (PA). We tested whether chronic stress-related ACTH-mediated ALD hypersecretion and/or zona glomerulosa hypersensitivity could be implicated in the pathogenesis of essential hypertension (ESHT). One hundred thirteen hypertensives without PA and 61 normotensive controls underwent an ultralow-dose (0.03-μg) ACTH stimulation and a treadmill test. Patients with ALD hyper-response according to the cutoffs obtained from controls received treatment with MRAs and underwent genomic DNA testing for the presence of the CYP11B1/CYP11B2 chimeric gene and KCNJ5 gene mutations. A control group of 22 patients with simple ESHT received treatment with MRAs. Based on the cutoffs of ALD and aldosterone-to-renin ratio (ARR) post-ACTH stimulation obtained from controls, 30 patients (27%) exhibited an ALD but not cortisol (F) hyper-response (HYPER group). This group had no difference in basal ACTH/renin (REN) concentrations compared with controls and the 83 patients with hypertension (73%) without an ALD hyper-response to ACTH stimulation. Patients in the HYPER group demonstrated significantly higher ALD concentrations, ARR, and ALD/ACTH ratio (AAR) in the treadmill test. Treatment with MRAs alone produced normalization of blood pressure in these patients whereas patients with hypertension with neither PA nor ALD hyper-response to ACTH stimulation who served as a control group failed to lower blood pressure. Also, two novel germline heterozygous KCNJ5 mutations were detected in the HYPER group. A number of patients with hypertension without PA show ACTH-dependent ALD hyper-secretion and benefit from treatment with MRAs. This could be related to chronic stress via ACTH hyper secretion and/or gene-mutations increasing the

  5. Pharmacologic management of angioedema induced by angiotensin-converting enzyme inhibitors.

    Science.gov (United States)

    Scalese, Michael J; Reinaker, Travis S

    2016-06-15

    The published evidence on pharmacologic approaches to the management of angiotensin-converting enzyme inhibitor (ACEI)-induced angioedema is reviewed. Angioedema is a serious, potentially life-threatening adverse effect of ACEI use. Although the underlying mechanism is not fully understood, excess bradykinin produced through a complex interplay between the kallikrein-kinin and renin-angiotensin-aldosterone systems is thought to play a major role. The nonallergic nature of the reaction renders traditional therapies (corticosteroids and antihistamines) ineffective because those agents do not modify the proposed pathophysiology. Fresh frozen plasma (FFP) provides kinase II, a protein that breaks down bradykinin. Case reports support FFP as a treatment for ACEI-induced angioedema, but no formal evaluations have been completed to date. Both ecallantide and complement 1 esterase (C1) inhibitor concentrate reduce bradykinin production through upstream inhibition of kallikrein. C1 inhibitor concentrate has been used successfully to manage ACEI-induced angioedema in a few reported cases, but robust supportive studies are lacking. Conversely, ecallantide has been evaluated in multiple randomized trials but has not been shown to offer advantages over traditional therapies. The use of icatibant, a direct antagonist of bradykinin B2 receptors, was reported to be beneficial in several case reports and in a small Phase II study, safely and rapidly reducing symptoms of ACEI-induced angioedema. An ongoing Phase III trial (NCT01919801) will better define the role of icatibant in the management of ACEI-induced angioedema. FFP, C1 inhibitor, and icatibant appear to be safe and effective therapeutic options for the management of ACEI-induced angioedema, whereas it appears ecallantide should be avoided. Copyright © 2016 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

  6. Angiotensin-converting enzyme insertion/deletion gene polymorphism in Egyptian children with systemic lupus erythematosus: a possible relation to proliferative nephritis.

    Science.gov (United States)

    Hammad, A; Yahia, S; Laimon, W; Hamed, S M; Shouma, A; Shalaby, N M; Abdel-Hady, D; Ghanem, R; El-Farahaty, R M; El-Bassiony, S R; Hammad, E M

    2017-06-01

    Introduction Angiotensin-converting enzyme (ACE) is crucial in the pathogenesis of systemic lupus erythematosus through angiotensin II which regulates vascular tone and endothelial functions. Objectives To study the frequency of ACE insertion/deletion (I/D) gene polymorphism in Egyptian children with systemic lupus erythematosus and its possible relation to the renal pathology in cases with lupus nephritis. Subjects and methods The frequency of ACE gene insertion/deletion polymorphism genotypes was determined in 78 Egyptian children with systemic lupus erythematosus and compared to a matched group of 140 healthy controls using polymerase chain reaction. Results The DD genotype of the ACE gene was higher in systemic lupus erythematosus patients when compared to controls ( Plupus erythematosus patients in comparison to controls ( P lupus nephritis group, the DD genotype was significantly higher in those with proliferative lupus nephritis when compared to those with non-proliferative lupus nephritis ( P = 0.02; OR = 1.45; 95% CI = 1.4-1.6). Also, patients with proliferative lupus nephritis showed a higher frequency of the D allele ( P lupus erythematosus and occurrence of proliferative nephritis in Egyptian children.

  7. Changes of serum aldosterone levels in patients with different stages of chronic renal insufficiency

    International Nuclear Information System (INIS)

    Zou Jun; Du Xueliang; Jiang Gengru

    2005-01-01

    Objective: To study the correlationship between the serum aldosterone levels and different stages of chronic renal insufficiency. Methods: Plasma renin activity (PRA), serum angiotensin II (Ang II) contents and serum aldosterone concentration (SACs) were determined with RIA in 42 patients with chronic renal insufficiency from various causes. The patients were divided into three groups according to their endogenous creatinine clearance rate: Group 1, (n=14) Ccr≥60ml/(min·1.73m 2 ); Group 2, (n =13) 20ml/(min·1.73m 2 ) ≤Ccr 2 ); Group 3, (n=15) Ccr 2 ). Results: The SACs values in Group 3 patients were significantly higher than those in Group 1 and Group 2 patients (P<0.01). The SACs values in Group 2 patients were also significantly higher than those in Group 1 patients (P<0.05). Ccr values were higher negatively correlated with the SACs values (r= -0.685, P<0.001). Conclusion: As the creatine clearance rate gradually deteriorated, the SACs values increased correspondingly in patients with chronic renal insufficiency from various causes. (authors)

  8. Renin-angiotensin system blockade alone or combined with ETA receptor blockade: effects on the course of chronic kidney disease in 5/6 nephrectomized Ren-2 transgenic hypertensive rats

    Czech Academy of Sciences Publication Activity Database

    Sedláková, L.; Čertíková; Chábová, V.; Doleželová, Š.; Škaroupková, P.; Kopkan, L.; Husková, Z.; Červenková, L.; Kikerlová, S.; Vaněčková, Ivana; Sadowski, J.; Kompanowska; Jezierska, E.; Kujal, P.; Kramer, H. J.; Červenka, L.

    2017-01-01

    Roč. 39, č. 2 (2017), s. 183-195 ISSN 1064-1963 Institutional support: RVO:67985823 Keywords : chronic kidney disease * endothelin system * hypertension * renin–angiotensin system * 5/6 nephrectomy Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery OBOR OECD: Cardiac and Cardiovascular systems Impact factor: 1.162, year: 2016

  9. Acute kidney injury secondary to a combination of renin-angiotensin system inhibitors, diuretics and NSAIDS: "The Triple Whammy".

    Science.gov (United States)

    Camin, Rosa Maria Garcia; Cols, Montse; Chevarria, Julio Leonel; Osuna, Rosa García; Carreras, Marc; Lisbona, Josep Maria; Coderch, Jordi

    2015-01-01

    Renin-angiotensin system inhibitors (ACEI/ARB-II), diuretics and NSAIDs, a combination known as "Triple Whammy", can result in decreased glomerular filtration rate (GFR) and acute kidney injury (AKI). Objectives: To describe the incidence of AKI for each drug type and their combinations. To define the profile of patients admitted for drug-related AKI secondary to Triple Whammy drugs (AKITW), with an assessment of costs and mortality. A retrospective observational 15-month study developed in three stages: - First: a cross-sectional stage to identify and describe hospitalizations due to AKITW. - Second: a follow-up stage of an outpatient cohort consuming these drugs (15,307 subjects). - Third: a cohort stage to assess costs and mortality, which compared 62 hospitalized patients with AKITW and 62 without AKI, paired by medical specialty, sex, age and comorbidity according to their Clinical Risk Groups. There were 85 hospitalization episodes due to AKITW, and 78% of patients were over the age of 70. The incidence of AKITW in the population was 3.40 cases/1000 users/year (95% CI: 2.59-4.45). By categories, these were: NSAIDs + diuretics 8.99 (95% CI: 3.16-25.3); Triple Whammy 8.82 (95% CI: 4.4-17.3); ACEI/ARB-II + diuretics 6.87 (95% CI: 4.81-9.82); and monotherapy with diuretics 3.31 (95% CI: 1.39-7.85). Mean hospital stay was 7.6 days (SD 6.4), and mean avoidable costs were estimated at €214,604/100,000 inhabitants/year. Mortality during hospitalization and at 12 months was 11.3% and 38.7% respectively, and there were no significant differences when compared with the control group. Treatment with ACEI, ARB-II, diuretics and/or NSAIDs shows a high incidence of hospitalization episodes due to AKI; diuretics as monotherapy or dual and triple combination therapy cause the highest incidence. AKITW involves high health care costs and avoidable mortality. Copyright © 2015. Published by Elsevier España, S.L.U.

  10. Dysregulation of microRNAs and renin-angiotensin system in high salt diet-induced cardiac dysfunction in uninephrectomized rats.

    Science.gov (United States)

    Amara, Venkateswara Rao; Surapaneni, Sunil Kumar; Tikoo, Kulbhushan

    2017-01-01

    Uninephrectomy is not associated with major adverse events in cardiovascular and renal functions of live kidney donors. The effect of high salt diet on the quality of life of live kidney donors is largely unknown. Hence in this study, we aimed to determine the effect of high salt diet on the alterations of renin-angiotensin system and microRNAs leading to CV and renal dysfunction in uninephrectomized rats. In order to mimic clinical scenario, uninephrectomized male Sprague Dawley rats were fed initially with normal pellet diet for 12 weeks and then for 20 weeks with high salt (10% w/w NaCl) diet. At the end of the study, biochemical, functional, histological and molecular parameters were measured. High salt diet feeding resulted in renal dysfunction & fibrosis, decreased baroreflex sensitivity, increased in vivo cardiovascular reactivity to angiotensin II owing to upregulation of angiotensin II type 1 receptors and L-type calcium channels leading to cardiovascular dysfunction in uninephrectomized rats (UNX+HSD) worse than that of normal (binephric) rats fed with high salt diet (HSD). Protein expression of functional and hypertrophic protein markers revealed decreased SERCA, p-AMPK and increased p-AKT. Interestingly, levels of miR-25, miR-451 and miR-155 increased and miR-99 decreased in heart of uninephrectomized rats fed with high salt. However, circulating miR-25 and miR-451 levels decreased and miR-99b increased in these animals. Our study points out that since tissue and circulating levels of miRNAs are not similar, caution must be exercised during the usage of miRs as diagnostic or prognostic biomarkers. To our knowledge, we are the first to show that epigenetic alterations result in cardiac dysfunction in uninephrectomized rats fed with high salt diet.

  11. Evaluation of the Clinical Utility of Renin-Angiotensin System Inhibitors in Patients Undergoing Radical Surgery for Urothelial Carcinoma of the Upper Urinary Tract.

    Science.gov (United States)

    Yoshida, Takashi; Matsuzaki, Tomoaki; Murota, Takashi; Kawa, Gen; Matsuda, Tadashi; Kinoshita, Hidefumi

    2017-12-01

    Renin-angiotensin system (RAS) inhibitors are effective for treating patients with cancer. The present study evaluated the impact of RAS inhibitors, including angiotensin-2 converting enzyme inhibitors and angiotensin 2 receptor blockers, after patients underwent radical surgery for upper urinary tract urothelial carcinoma (UTUC). This retrospective study included 312 patients with nonmetastatic UTUC who underwent radical surgery. The oncological outcomes of patients treated or not treated with RAS inhibitors following surgery were evaluated. Recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) were assessed using the Kaplan-Meier method and Cox regression analysis. The median follow-up duration after radical surgery was 44.7 months. The 5-year RFS, CSS, and OS rates of patients who did or did not receive RAS inhibitors were 82.3% versus 68.9% (P = .018), 88.9% versus 71.8% (P = .0044), and 68.7% versus 61.8% (P = .047), respectively. Multivariable analyses revealed that the use of RAS inhibitors was an independent prognostic factor for RFS, CSS, and OS (hazard ratio [HR] 0.48, P = .013; HR 0.31, P = .002; and HR 0.52, P = .01, respectively). Moreover, patients treated with RAS inhibitors versus untreated patients had better 5-year RFS compared with those in the pT2 and < pN1 subgroups (pT2: 100.0% vs. 62.2%, P = .014 and < pN1: 87.2% vs. 74.7%, P = .034). RAS inhibitors significantly improved RFS, CSS, and OS of patients with UTUC who underwent radical surgery. These agents may be particularly beneficial for patients with stage pT2 or < pN1 disease. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Endoplasmic reticulum stress increases brain MAPK signaling, inflammation and renin-angiotensin system activity and sympathetic nerve activity in heart failure.

    Science.gov (United States)

    Wei, Shun-Guang; Yu, Yang; Weiss, Robert M; Felder, Robert B

    2016-10-01

    We previously reported that endoplasmic reticulum (ER) stress is induced in the subfornical organ (SFO) and the hypothalamic paraventricular nucleus (PVN) of heart failure (HF) rats and is reduced by inhibition of mitogen-activated protein kinase (MAPK) signaling. The present study further examined the relationship between brain MAPK signaling, ER stress, and sympathetic excitation in HF. Sham-operated (Sham) and HF rats received a 4-wk intracerebroventricular (ICV) infusion of vehicle (Veh) or the ER stress inhibitor tauroursodeoxycholic acid (TUDCA, 10 μg/day). Lower mRNA levels of the ER stress biomarkers GRP78, ATF6, ATF4, and XBP-1s in the SFO and PVN of TUDCA-treated HF rats validated the efficacy of the TUDCA dose. The elevated levels of phosphorylated p44/42 and p38 MAPK in SFO and PVN of Veh-treated HF rats, compared with Sham rats, were significantly reduced in TUDCA-treated HF rats as shown by Western blot and immunofluorescent staining. Plasma norepinephrine levels were higher in Veh-treated HF rats, compared with Veh-treated Sham rats, and were significantly lower in the TUDCA-treated HF rats. TUDCA-treated HF rats also had lower mRNA levels for angiotensin converting enzyme, angiotensin II type 1 receptor, tumor necrosis factor-α, interleukin-1β, cyclooxygenase-2, and NF-κB p65, and a higher mRNA level of IκB-α, in the SFO and PVN than Veh-treated HF rats. These data suggest that ER stress contributes to the augmented sympathetic activity in HF by inducing MAPK signaling, thereby promoting inflammation and renin-angiotensin system activity in key cardiovascular regulatory regions of the brain.

  13. Increased sensitivity to angiotensin II is present postpartum in women with a history of hypertensive pregnancy.

    Science.gov (United States)

    Saxena, Aditi R; Karumanchi, S Ananth; Brown, Nancy J; Royle, Caroline M; McElrath, Thomas F; Seely, Ellen W

    2010-05-01

    Pregnancies complicated by new-onset hypertension are associated with increased sensitivity to angiotensin II, but it is unclear whether this sensitivity persists postpartum. We studied pressor response to infused angiotensin II in 25 normotensive postpartum women in both high- and low-sodium balance. Ten women had a history of hypertensive pregnancy (5 with preeclampsia; 5 with transient hypertension of pregnancy), and 15 women had a history of uncomplicated, normotensive pregnancy. Systolic and diastolic blood pressures, aldosterone, and soluble fms-like tyrosine kinase 1 levels were measured before and after angiotensin II infusion in both dietary phases. In high sodium balance, women with a history of hypertensive pregnancy were normotensive but had significantly higher systolic and diastolic blood pressures than controls (115 versus 104 mm Hg and 73 versus 65 mm Hg, respectively; Phistory of hypertensive pregnancy had a pressor response to salt loading, demonstrated by an increase in systolic blood pressure on a high-salt diet. They also had greater systolic pressor response (10 versus 2 mm Hg; P=0.03), greater increase in aldosterone (56.8 versus 30.8 ng/dL; P=0.03), and increase in soluble fms-like tyrosine kinase 1 levels (11.0 versus -18.9 pg/mL; P=0.02) after infusion of angiotensin II in low-sodium balance compared with controls. Thus, women with a history of hypertensive pregnancy demonstrated salt sensitivity of blood pressure and had increased pressor, adrenal, and soluble fms-like tyrosine kinase 1 responses to infused angiotensin II in low-sodium balance. Increased sensitivity to angiotensin II observed during pregnancy in women with hypertensive pregnancy is present postpartum; this feature may contribute to future cardiovascular risk in these women.

  14. Plasma Molecular Signatures in Hypertensive Patients With Renin-Angiotensin System Suppression: New Predictors of Renal Damage and De Novo Albuminuria Indicators.

    Science.gov (United States)

    Baldan-Martin, Montserrat; Mourino-Alvarez, Laura; Gonzalez-Calero, Laura; Moreno-Luna, Rafael; Sastre-Oliva, Tamara; Ruiz-Hurtado, Gema; Segura, Julian; Lopez, Juan Antonio; Vazquez, Jesus; Vivanco, Fernando; Alvarez-Llamas, Gloria; Ruilope, Luis M; de la Cuesta, Fernando; Barderas, Maria G

    2016-07-01

    Albuminuria is a risk factor strongly associated with cardiovascular disease, the first cause of death in the general population. It is well established that renin-angiotensin system suppressors prevent the development of new-onset albuminuria in naïf hypertensive patients and diminish its excretion, but we cannot forget the percentage of hypertensive patients who develop de novo albuminuria. Here, we applied multiple proteomic strategy with the purpose to elucidate specific molecular pathways involved in the pathogenesis and provide predictors and chronic organ damage indicators. Briefly, 1143 patients were followed up for a minimum period of 3 years. One hundred and twenty-nine hypertensive patients chronically renin-angiotensin system suppressed were recruited, classified in 3 different groups depending on their albuminuria levels (normoalbuminuria, de novo albuminuria, and sustained albuminuria), and investigated by multiple proteomic strategies. Our strategy allowed us to perform one of the deepest plasma proteomic analysis to date, which has shown 2 proteomic signatures: (1) with predictive value of de novo albuminuria and (2) sustained albuminuria indicator proteins. These proteins are involved in inflammation, immune as well as in the proteasome activation occurring in situations of endoplasmic reticulum stress. Furthermore, these results open the possibility of a future strategy based on anti-immune therapy to treat hypertension which could help to prevent the development of albuminuria and, hence, the progression of kidney damage. © 2016 American Heart Association, Inc.

  15. Hypotensive and Angiotensin-Converting Enzyme Inhibitory Activities of Eisenia fetida Extract in Spontaneously Hypertensive Rats

    Directory of Open Access Journals (Sweden)

    Shumei Mao

    2015-01-01

    Full Text Available Objectives. This study aimed to investigate the antihypertensive effects of an Eisenia fetida extract (EFE and its possible mechanisms in spontaneously hypertensive rats (SHR rats. Methods. Sixteen-week-old SHR rats and Wistar-Kyoto rats (WKY rats were used in this study. Rats were, respectively, given EFE (EFE group, captopril (captopril group, or phosphate-buffered saline (PBS (normal control group and SHR group for 4 weeks. ACE inhibitory activity of EFE in vitro was determined. The systolic blood pressure (SBP and diastolic blood pressure (DBP were measured using a Rat Tail-Cuff Blood Pressure System. Levels of angiotensin II (Ang II, aldosterone (Ald, and 6-keto-prostaglandin F1 alpha (6-keto-PGF1α in plasma were determined by radioimmunoassay, and serum nitric oxide (NO concentration was measured by Griess reagent systems. Results. EFE had marked ACE inhibitory activity in vitro (IC50 = 2.5 mg/mL. After the 4-week drug management, SHR rats in EFE group and in captopril group had lower SBP and DBP, lower levels of Ang II and Ald, and higher levels of 6-keto-PGF1α and NO than the SHR rats in SHR group. Conclusion. These results indicate that EFE has hypotensive effects in SHR rats and its effects might be associated with its ACE inhibitory activity.

  16. Aldosterone synthase gene polymorphism in alimentary obesity, metabolic syndrome components, some secondary forms of arterial hypertension, pathology of the adrenals glands core (literature review

    Directory of Open Access Journals (Sweden)

    S.N. Koval

    2017-08-01

    populations. Europeans, Asians, Africans and North Americans were among them and were genotyped by CYP11B2. To date, there is ample evidence that fatty tissue (FT, apart from a source of energy, is an active endocrine organ that plays a key role in maintaining homeostasis and participating in the pathogenesis of a number of diseases. Its excess is accompanied by hyperactivation of tissue renin-angiotensin-aldosterone system (RAAS, strengthening of local and systemic synthesis of AL and the emergence of secondary aldosteronism. AL, in its turn, has a direct effect on FT due to increased MKR density expressed on adipocytes surface, leading to acceleration in the maturation of the latter and a further increase in FT. Getting into the systemic blood circulation and effecting other organs, the excess AL promotes the development of insulin resistance, atherosclerosis, the progression of systemic inflammatory reactions. MKR activation in FT plays not only the key role in sodium reabsorption by kidneys and the control of BP, but also in the differentiation of preadipocytes into mature adipocytes in FT, induction of inflammation and hyperproduction of cytokines — tumor necrotic factor alpha (TNF-α, monocyte chemotactic protein (MCP-1 and interleukin 6 (IL-6 in the white FT, a decrease in the thermogenic activity and trans­cription of the uncoupling protein-1 (UCP-1 in brown FT. MCR hyperactivation was detected in mice with AO (obese db/db mice, associated with increased BMI in humans and contributes to the development of IR and associated with AO cardiovascular diseases. The gene polymorphism of AS may be a marker of aggravated pregnancy, the presence of gestational hypertension or pre-eclampsia. Some studies found that AS gene polymorphism can affect plasma glucose levels. AS gene polymorphism was not associated with the progression of diabetic nephropathy (DN, but is associated with AH in persons with type 2 diabetes mellitus. National authors conclude about the association

  17. Gonadotropin-Releasing Hormone Stimulate Aldosterone Production in a Subset of Aldosterone-Producing Adenoma

    Science.gov (United States)

    Kishimoto, Rui; Oki, Kenji; Yoneda, Masayasu; Gomez-Sanchez, Celso E.; Ohno, Haruya; Kobuke, Kazuhiro; Itcho, Kiyotaka; Kohno, Nobuoki

    2016-01-01

    Abstract We aimed to detect novel genes associated with G protein-coupled receptors (GPCRs) in aldosterone-producing adenoma (APA) and elucidate the mechanisms underlying aldosterone production. Microarray analysis targeting GPCR-associated genes was conducted using APA without known mutations (APA-WT) samples (n = 3) and APA with the KCNJ5 mutation (APA-KCNJ5; n = 3). Since gonadotropin-releasing hormone receptor (GNRHR) was the highest expression in APA-WT by microarray analysis, we investigated the effect of gonadotropin-releasing hormone (GnRH) stimulation on aldosterone production. The quantitative polymerase chain reaction assay results revealed higher GNRHR expression levels in APA-WT samples those in APA-KCNJ5 samples (P APA-WT samples, and there was a significant and positive correlation between GNRHR and LHCGR expression in all APA samples (r = 0.476, P APA-WT (n = 9), which showed higher GNRHR and LHCGR levels, had significantly higher GnRH-stimulated aldosterone response than those with APA-KCNJ5 (n = 13) (P APA-WT, and the molecular analysis including the receptor expression associated with clinical findings of GnRH stimulation. PMID:27196470

  18. Angiotensin-(1-7) : Pharmacological properties and pharmacotherapeutic perspectives

    NARCIS (Netherlands)

    Iusuf, Dilek; Henning, Robert H.; van Gilst, Wiek H.; Roks, Anton J. M.

    2008-01-01

    Therapeutic modulation of the renin-angiotensin system is not complete without taking into consideration the beneficial effects of angiotensin-(1-7) in cardiovascular pathology. Various pharmacological pathways are already exploited to involve this heptapeptide in therapy as both inhibitors of

  19. Mitochondrial uncoupling proteins regulate angiotensin-converting enzyme expression

    DEFF Research Database (Denmark)

    Dhamrait, Sukhbir S.; Maubaret, Cecilia; Pedersen-bjergaard, Ulrik

    2016-01-01

    Uncoupling proteins (UCPs) regulate mitochondrial function, and thus cellular metabolism. Angiotensin-converting enzyme (ACE) is the central component of endocrine and local tissue renin–angiotensin systems (RAS), which also regulate diverse aspects of whole-body metabolism and mitochondrial...

  20. Mitochondrial uncoupling proteins regulate angiotensin-converting enzyme expression

    DEFF Research Database (Denmark)

    Dhamrait, Sukhbir S.; Maubaret, Cecilia; Pedersen-Bjergaard, Ulrik

    2016-01-01

    Uncoupling proteins (UCPs) regulate mitochondrial function, and thus cellular metabolism. Angiotensin-converting enzyme (ACE) is the central component of endocrine and local tissue renin-angiotensin systems (RAS), which also regulate diverse aspects of whole-body metabolism and mitochondrial...

  1. The therapeutic effect of a new angiotensin-converting enzyme inhibitor, enalapril maleate, in idiopathic hyperaldosteronism.

    Science.gov (United States)

    Griffing, G T; Melby, J C

    1985-09-01

    Patients with idiopathic hyperaldosteronism (IHA) manifest hypertension, hypokalemia, and renin suppression. IHA is thought to have one of three possible etiologies: zona glomerulosa autonomy, an aldosterone secretory factor, or angiotensin-II (A-II) adrenal hypersensitivity. To determine the contribution of A-II adrenal hypersensitivity in IHA, four patients with IHA were treated with a new angiotensin-converting enzyme inhibitor, enalapril, on a controlled diet (sodium [128 mEq/day] and potassium [80 mEq/day]) in a metabolic unit. The results of this study demonstrate that enalapril therapy in three of four patients normalized blood pressure, improved potassium balance, elevated PRA, reversed the postural increment in plasma aldosterone concentration (PAC), and reduced aldosterone secretion to normal. The fourth patient with bilateral macronodular disease, on the other hand, had no improvement in any of the above indices, despite maximal doses of enalapril (80 mg/day). This patient, however, may have had bilateral adrenal adenomas, based on extremely elevated 18-OH-corticosterone levels (greater than 100 ng/dl), and because of a lack of adrenal A-II hypersensitivity, demonstrated by a fall in pre-enalapril, postural-, and lasix-induced PAC. In conclusion, enalapril improved the hypertension, hypokalemia, renin suppression, and hyperaldosteronism in three patients with IHA over 28 days of therapy. The results of this study suggest an etiologic role of A-II adrenal hypersensitivity in IHA.

  2. Chronic blockade of angiotensin II action prevents glomerulosclerosis, but induces graft vasculopathy in experimental kidney transplantation

    NARCIS (Netherlands)

    Smit-van Oosten, A; Navis, G; Stegeman, CA; Joles, JA; Klok, PA; Kuipers, F; Tiebosch, ATMG; van Goor, H

    Long-term renin-angiotensin system blockade is beneficial in a variety of renal diseases, This study examines the long-term (34 weeks) effects of the angiotensin-converting enzyme inhibitor lisinopril and the angiotensin II receptor type I blocker L158,809 in the Fisher to Lewis rat model of chronic

  3. Angiotensin II, tissue factor and the thrombotic paradox of hypertension.

    Science.gov (United States)

    Celi, Alessandro; Cianchetti, Silvana; Dell'Omo, Giulia; Pedrinelli, Roberto

    2010-12-01

    Tissue factor (TF), the physiologic initiator of blood coagulation, may contribute to the increased risk of thrombotic complications that characterizes arterial hypertension, as suggested by hypertensive animal models showing evidence for TF activation, and clinical studies in hypertensive patients at higher cardiovascular risk with increased circulating levels of TF and thrombogenic microparticles. Angiotensin II stimulates TF expression both in vitro and in vivo, an effect abolished by ACE or angiotensin II receptor inhibition. Moreover, renin-angiotensin system blockers, including aliskiren, a direct renin inhibitor, are able to modulate TF expression in monocytes and vascular endothelial cells activated by inflammatory cytokines. This behavior is suggestive of anti-inflammatory and anti-thrombotic properties of renin-angiotensin system blockers, and is compatible with the possibility that blocking local renin-angiotensin system activation might downregulate TF, thus reducing the risk of ischemic complications in hypertensive patients.

  4. [Effect of noradrenaline and angiotensin II on the brain and kidney blood supply with changes in systemic arterial pressure].

    Science.gov (United States)

    Beketov, A I; Korneliuk, I K

    1981-01-01

    Hydrogen clearance was used in experiments on anesthetized cats to demonstrate that intravenous infusions of noradrenaline induced an increase in cerebral blood supply and reduction of renal blood flow both in anesthetized animals and in the presence of hypotension. In these conditions, angiotensin II lowered the cerebral and renal blood flow. Hypotension enhanced the reactions of the cerebral and renal blood flow to the action of vasopressor agents. The intensity of the reactions was consistent with the degree of vascular autocontrol preservation in the brain and kidneys.

  5. Effect of L-5-Hydroxytryptophan on drinking behavior in Coturnix japonica (Temminck and Schlegel, 1849 (Galliformes: Aves: involvement of renin-angiotensin system

    Directory of Open Access Journals (Sweden)

    PL Cedraz-Mercez

    Full Text Available The purpose of this study was to explore the role of L-5-hydroxytryptophan (L-HTP and its relationship with the renin-angiotensin system (RAS on the drinking behavior in Japanese quails. Normally-hydrated quails that received injections of L-HTP (12.5; 25 and 50 mg.kg-1 by the intracoelomic route (ic expressed an increase in water intake, which was inhibited by captopril, an angiotensin converting enzyme (ACE inhibitor. In addition, captopril also induced such a response in birds under previous fluid deprivation. High doses of captopril (35-70 mg.kg-1, sc in normally-hydrated quails decreased the spontaneous water intake while low doses of captopril (2-5 mg.kg-1, sc did not prompt water intake after L-HTP administration. Losartan, an AT1 receptor antagonist in mammals, did not change the water intake levels in normally-hydrated or water-deprivated birds. Serotonin (5-HT injections did not provoke its known dipsogenic response.

  6. The regulation of cell growth and survival by aldosterone.

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2011-01-01

    The steroid hormone aldosterone is synthesized from cholesterol, mainly in the zona glomerulosa of the adrenal cortex. Aldosterone exerts its effects in the epithelial tissues of the kidney and colon and in non-epithelial tissues such as the brain and cardiovasculature. The genomic response to aldosterone involves dimerization of the mineralocorticoid receptor (MR), dissociation of heat shock proteins from MR, translocation of the aldosterone-MR complex to the nucleus and the concomitant regulation of gene expression. Rapid responses to aldosterone occur within seconds to minutes, do not involve transcription or translation and can modulate directly or indirectly the later genomic responses. Aside from the well-known effects of aldosterone on the regulation of sodium and water homeostasis, aldosterone can also produce deleterious structural changes in tissues by inducing hypertrophy and the dysregulation of proliferation and apoptosis, leading to fibrosis and tissue remodelling. Here we discuss the involvement of aldosterone-mediated rapid signalling cascades in the development of disease states such as chronic kidney disease and heart failure, and the antagonists that can inhibit these pathophysiological responses.

  7. The regulation of cell growth and survival by aldosterone.

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2012-02-01

    The steroid hormone aldosterone is synthesized from cholesterol, mainly in the zona glomerulosa of the adrenal cortex. Aldosterone exerts its effects in the epithelial tissues of the kidney and colon and in non-epithelial tissues such as the brain and cardiovasculature. The genomic response to aldosterone involves dimerization of the mineralocorticoid receptor (MR), dissociation of heat shock proteins from MR, translocation of the aldosterone-MR complex to the nucleus and the concomitant regulation of gene expression. Rapid responses to aldosterone occur within seconds to minutes, do not involve transcription or translation and can modulate directly or indirectly the later genomic responses. Aside from the well-known effects of aldosterone on the regulation of sodium and water homeostasis, aldosterone can also produce deleterious structural changes in tissues by inducing hypertrophy and the dysregulation of proliferation and apoptosis, leading to fibrosis and tissue remodelling. Here we discuss the involvement of aldosterone-mediated rapid signalling cascades in the development of disease states such as chronic kidney disease and heart failure, and the antagonists that can inhibit these pathophysiological responses.

  8. Aldosterone and parathyroid hormone: a precarious couple for cardiovascular disease

    NARCIS (Netherlands)

    Tomaschitz, A.; Ritz, E.; Pieske, B.; Fahrleitner-Pammer, A.; Kienreich, K.; Horina, J.H.; Drechsler, C.; Marz, W.; Ofner, M.; Pieber, T.R.; Pilz, S.

    2012-01-01

    Animal and human studies support a clinically relevant interaction between aldosterone and parathyroid hormone (PTH) levels and suggest an impact of the interaction on cardiovascular (CV) health. This review focuses on mechanisms behind the bidirectional interactions between aldosterone and PTH and

  9. Low sodium diet inhibits the local counter-regulator effect of angiotensin-(1-7) on angiotensin II

    NARCIS (Netherlands)

    Roks, Anton J M; Nijholt, Jeroen; van Buiten, Azuwerus; van Gilst, Wiek H; de Zeeuw, Dick; Henning, Robert H

    2004-01-01

    Objective The heptapeptide angiotensin-(1-7) [Ang-(1-7)] has been identified as a versatile, endogenous inhibitor of the renin-angiotensin system (RAS). As the therapeutic response to exogenous RAS inhibitors, such as AT, receptor antagonists, is altered by changes in salt intake, we investigated

  10. Effects of angiotensin II and angiotensin II type 1 receptor blockade on neointimal formation after stent implantation

    NARCIS (Netherlands)

    Groenewegen, Hendrik C.; van der Harst, Pim; Roks, Anton J. M.; Buikema, Hendrik; Zijlstra, Felix; van Gilst, Wiek H.; de Smet, Bart J. G. L.

    2008-01-01

    Background: To evaluate the effect of supraphysiological levels of angiotensin II and selective angiotensin II type 1 receptor ( AT1-receptor) blockade on neointimal formation and systemic endothelial function after stent implantation in the rat abdominal aorta. Methods: Male Wistar rats were

  11. Effect of wood combustion smoke inhalation on angiotensin-1-converting enzyme in the dog

    Energy Technology Data Exchange (ETDEWEB)

    Brizio-Molteni, L.; Piano, G.; Rice, P.L.; Warpeha, R.; Fresco, R.; Solliday, N.H.; Molteni, A.

    One lung of each dog was exposed to smoke from burning pine wood, while the other was subjected to acute hypoxia. Angiotensin-1-converting enzyme (ACE) activity in biopsied tissue of the smoke-exposed lung was markedly increased immediately after the injury and even higher 30 minutes later. No change in ACE activity was observed in the hypoxic contralateral lung. Serum ACE activity did not change significantly following anesthesia and before smoke inhalation. Serum aldosterone and cortisol levels increased at this juncture. Smoke inhalation caused intra-alveolar hemorrhages and edema. Pulmonary and systolic, diastolic and mean pressures, pulmonary capillary, wedge pressure, cardiac output and systemic and pulmonary arteriolar resistances remained unchanged throughout the experiment. The changes of ACE activity are presumably a direct effect of smoke inhalation. They are seen as an early response of the lung endothelial cells to many types of injury (chronic hypoxia, bleomycin or monocrotaline administration) and may represent an important step in the development of the organ's response to the injury.

  12. Genetic variation in angiotensin II type 2 receptor gene influences extent of left ventricular hypertrophy in hypertrophic cardiomyopathy independent of blood pressure.

    Science.gov (United States)

    Carstens, Nadia; van der Merwe, Lize; Revera, Miriam; Heradien, Marshall; Goosen, Althea; Brink, Paul A; Moolman-Smook, Johanna C

    2011-09-01

    Hypertrophic cardiomyopathy (HCM), an inherited primary cardiac disorder mostly caused by defective sarcomeric proteins, serves as a model to investigate left ventricular hypertrophy (LVH). HCM manifests extreme variability in the degree and distribution of LVH, even in patients with the same causal mutation. Genes coding for renin-angiotensin-aldosterone system components have been studied as hypertrophy modifiers in HCM, with emphasis on the angiotensin (Ang) II type 1 receptor (AT(1)R). However, Ang II binding to Ang II type 2 receptors (AT(2)R) also has hypertrophy-modulating effects. We investigated the effect of the functional +1675 G/A polymorphism (rs1403543) and additional single nucleotide polymorphisms in the 3' untranslated region of the AT(2)R gene (AGTR2) on a heritable composite hypertrophy score in an HCM family cohort in which HCM founder mutations segregate. We find significant association between rs1403543 and hypertrophy, with each A allele decreasing the average wall thickness by ~0.5 mm, independent of the effects of the primary HCM causal mutation, blood pressure and other hypertrophy covariates (p = 0.020). This study therefore confirms a hypertrophy-modulating effect for AT(2)R also in HCM and implies that +1675 G/A could potentially be used in a panel of markers that profile a genetic predisposition to LVH in HCM.

  13. Pseudoaldosteronism due to the concurrent use of two herbal medicines containing glycyrrhizin: interaction of glycyrrhizin with angiotensin-converting enzyme inhibitor.

    Science.gov (United States)

    Iida, Rinako; Otsuka, Yasushi; Matsumoto, Kei; Kuriyama, Satoru; Hosoya, Tatsuo

    2006-06-01

    A 77-year-old man with a history of hypertension and hyperuricemia was admitted to our hospital complaining of limb weakness, persistent constipation, and worsening hypertension. He had been taking a Chinese herbal remedy for allergic rhinitis for the past 10 years, together with an angiotensin-converting enzyme inhibitor (ACE-I; enalapril, 20 mg daily). After the dosage of enalapril had been reduced to 10 mg daily about 1(1/2) years before the current admission, he had developed persistent constipation. Therefore, he had started taking another traditional Chinese herbal remedy, a laxative, for the constipation, about 4 months prior to this hospitalization. Laboratory data on admission demonstrated marked metabolic alkalosis with severe hypokalemia associated with urinary wasting of potassium and chloride. A diagnosis of pseudoaldosteronism was made based upon his past history of exposure to various traditional Chinese medicines containing glycyrrhizin. Discontinuation of the Chinese remedies and supplementation of potassium successfully normalized the electrolyte imbalance and relieved all symptoms within a short time. The present case describes the occurrence of pseudoaldosteronism induced by a patient taking two traditional Chinese herbs, both containing glycyrrhizin, resulting in an overdose of this causative chemical agent. The development of pseudoaldosteronism appeared to be of particular interest with regard to the interaction of the renin-angiotensin-aldosterone (RAA) system with glycyrrhizin, in which an ACE-I retarded the development of pseudoaldosteronism.

  14. Angiotensin-converting enzyme

    DEFF Research Database (Denmark)

    Sørensen, P G; Rømer, F K; Cortes, D

    1984-01-01

    In order to evaluate bleomycin-associated lung damage in humans, lung function parameters and serum levels of the endothelial-bound angiotensin-converting enzyme (ACE) were determined by serial measurements in 11 patients who were treated for testicular cancer. None developed clinical or radiolog......In order to evaluate bleomycin-associated lung damage in humans, lung function parameters and serum levels of the endothelial-bound angiotensin-converting enzyme (ACE) were determined by serial measurements in 11 patients who were treated for testicular cancer. None developed clinical...

  15. Is the use of renin-angiotensin system inhibitors in patients with aortic valve stenosis safe and of prognostic benefit?

    DEFF Research Database (Denmark)

    Andersson, Charlotte; Abdulla, Jawdat

    2017-01-01

    risk [576/3389 patients receiving RASi vs. 1118/4384 controls died; relative risk 0.93 (95% confidence interval 0.78-1.11), P = 0.44]. Use of RASi was also observed to lower the risk of aortic valve replacement (AVR) surgery [67/2913 patients with RASi vs. 154/3666 controls underwent AVR; relative risk......Aortic valve stenosis (AVS) is associated with significant morbidity and mortality, especially in the presence of symptoms and echocardiographic signs of left ventricular remodelling (i.e. increase in left ventricular mass, left ventricular dilation, and systolic dysfunction). Renin...... for inclusion (PubMed, EMBASE, and Cochrane library search criteria: aortic stenosis, aortic valve, angiotensin-converting enzyme inhibitor in different combinations, published in English at any time up to 1 April 2016). Our analyses suggested that use of RASi was safe, with no observed increase in mortality...

  16. Cognitive performance, symptoms and counter-regulation during hypoglycaemia in patients with type 1 diabetes and high or low renin-angiotensin system activity

    DEFF Research Database (Denmark)

    Høi-Hansen, Thomas; Pedersen-Bjergaard, Ulrik; Andersen, Rikke Due

    2009-01-01

    potentials and hypoglycaemic symptoms were recorded. RESULTS: At a hypoglycaemic nadir of 2.2 (SD 0.3) mmol/L the high RAS group displayed significant deterioration in cognitive performance during hypoglycaemia in the three most complex reaction time tasks. In the low RAS group, hypoglycaemia led......INTRODUCTION: High basal renin-angiotensin system (RAS) activity is associated with increased risk of severe hypoglycaemia in type 1 diabetes. We tested whether this might be explained by more pronounced cognitive dysfunction during hypoglycaemia in patients with high RAS activity than in patients...... with low RAS activity. MATERIALS AND METHODS: Nine patients with type 1 diabetes and high and nine with low RAS activity were subjected to hypoglycaemia and euglycaemia in a cross-over study using an intravenous insulin infusion protocol. Cognitive function, electroencephalography, auditory evoked...

  17. Biosynthesis of Various Steroids in vitro by Isolated Adrenal Cells in Primary Aldosteronism, Cushing's Syndrome, and Adrenogenital Syndrome due to Adrenocortical Adenoma

    OpenAIRE

    MIZUNO, SHIGERU; FUNAHASHI, HIROOMI

    1981-01-01

    To a further understanding of the role of steroid hormones in adrenal disorders, we have prepared free cell system of adrenal cells, using adrenal tissues that had been removed by operation from (i) cases of Cushing's syndrome due to adrenocortical adenoma or adrenocortical hyperplasia, (ii) a case of primary aldosteronism, and (iii) a patient with virilizing adrenal tumor. Twelve important steroid hormones were measured, such as pregnenolone, cortisol and aldosterone, which were produced by ...

  18. The impact of age and sex on the reporting of cough and angioedema with renin-angiotensin system inhibitors: a case/noncase study in VigiBase.

    Science.gov (United States)

    Alharbi, Fawaz F; Kholod, Anzhelika A V; Souverein, Patrick C; Meyboom, Ronald H; de Groot, Mark C H; de Boer, Anthonius; Klungel, Olaf H

    2017-12-01

    The purpose of this study was to assess the impact of age and sex on the reporting of cough and angioedema related to renin-angiotensin system (RAS) inhibitors. A case/noncase study was performed in VigiBase. Two case groups were identified, reports of cough and reports of angioedema, and noncases were all reports of all other adverse events. Logistic regression analysis was used to assess the association between reporting of cough and angioedema with each class of RAS inhibitors stratified by age/sex and to control for confounding. The reporting of cough with angiotensin-converting enzyme (ACE) inhibitors was significantly higher in women than in men [adjusted reporting odds ratio (ROR): 44.0, 95% CI (43.2-44.8) for women vs. 29.2, 95% CI (28.5-29.9) for men]. There was no difference in reporting of cough linked to angiotensin receptor blockers (ARBs) and aliskiren between men and women. In contrast, the reporting of angioedema with ACE inhibitors and ARBs was significantly higher in men than in women, but for aliskiren, women had a significantly higher ROR than men [adjusted ROR: 5.20, 95% CI (4.18-6.46) for women vs. 3.04, 95% CI (2.30-4.02) for men]. The reporting of cough with ACE inhibitors was increased with age until reaching a plateau at middle adulthood (40-59 years) and the reporting of angioedema with ACE inhibitors was increased with age until elderly (60-79 years). Age had only a slight effect on the reporting of cough and angioedema with ARBs and aliskiren. Both age and sex have substantial effects on the reporting of cough and angioedema with RAS inhibitors and in particular ACE inhibitors. Further study is needed to determine whether these differences mainly express different adverse drug reaction risks in subgroups or also can be explained by factors influencing reporting. © 2017 The Authors. Fundamental & Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of Société Française de Pharmacologie et de Thérapeutique.

  19. Potential impact of renin-angiotensin system inhibitors and calcium channel blockers on plasma high-molecular-weight adiponectin levels in hemodialysis patients

    International Nuclear Information System (INIS)

    Nakagawa, Naoki; Yao, Naoyuki; Hirayama, Tomoya

    2011-01-01

    Although metabolic syndrome confers an increased risk of cardiovascular disease in the general population, little is known about the alteration of abdominal adiposity and its association with adipocytokines in hemodialysis patients. We investigated the plasma high-molecular-weight (HMW) adiponectin level and its relationship to visceral fat area (VFA) and various markers of atherosclerosis in hemodialysis patients. In a cross-sectional study, conventional cardiovascular risk factors, plasma total and HMW adiponectin, the number of components of the metabolic syndrome and, using computed tomography, the distribution of abdominal adiposity were assessed in 144 hemodialysis patients (90 men and 54 women; mean age, 60.7 years) and 30 age- and sex-matched patients with chronic kidney disease (CKD). Plasma HMW adiponectin levels in hemodialysis patients were significantly higher than those in patients with CKD, negatively associated with VFA and serum triglycerides and positively associated with plasma total adiponectin, as well as the HMW-to-total adiponectin ratio in men and women (all P<0.05) in a simple regression analysis. In a multiple regression analysis, VFA was a significant determinant of HMW adiponectin in hemodialysis patients. Furthermore, after adjustment for classical risk factors, HMW adiponectin levels were significantly higher in patients undergoing treatment with renin-angiotensin system inhibitors or calcium channel blockers compared with patients not undergoing such treatment. This study shows that plasma HMW adiponectin levels were negatively associated with VFA and positively associated with treatment with blockade of the renin-angiotensin system and of the calcium channel. Therefore, these drugs might be effective for improving adipocytokine-related metabolic abnormalities in hemodialysis patients. (author)

  20. Acute Aldosterone-mediated Signaling Networks in Distal Convoluted Tubules

    DEFF Research Database (Denmark)

    Cheng, Lei; Wu, Qi; Olesen, Emma T. B.

    2017-01-01

    The kidney distal convoluted tubule (DCT) plays an important role in modulating body sodium balance and blood pressure. Long-term effects of aldosterone to increase sodium reabsorption in the DCT are well described. However, potential effects of aldosterone to acutely modulate DCT function via non...... in abundance following aldosterone treatment. The EGFR, ERK1/2, AKT, GSK3B and P70S6K were predicted to be important pathway nodes based on the quantitative proteomics data using network analysis. Ex vivo studies in isolated mouse cortical tubules demonstrated an increase in phosphorylated (active) NCC...

  1. Effects of Renin-Angiotensin System Inhibitors on Renal Expression of Renalase in Sprague-Dawley Rats Fed With High Salt Diet.

    Science.gov (United States)

    Wang, Yang; Xie, Bing-Qing; Gao, Wei-Hua; Yan, Ding-Yi; Zheng, Wen-Ling; Lv, Yong-Bo; Cao, Yu-Meng; Hu, Jia-Wen; Yuan, Zu-Yi; Mu, Jian-Jun

    2015-01-01

    The aim of our study was to investigate the effect of high-salt diet on the renal expression of renalase and the potential role of the local renin-angiotensin system in this process. Sprague-Dawley (SD) rats were divided into groups according to salt content in diet and drug treatment as follows: normal-salt diet (NS), high-salt diet (HS), high-salt intake with hydralazine (HS+H), high-salt diet with enalapril (HS+E), and high-salt diet with valsartan (HS+V). The dietary intervention and drugs were given for four weeks. Renin activity and angiotensin II type 1 receptor (AT1R) levels were detected by real-time PCR. Renalase mRNA and protein were also measured. After four weeks, systolic blood pressure and proteinuria were significantly increased in the HS group with respect to the NS group. Dietary salt intake caused a dramatic decrease in renalase expression in the rat kidneys. Renal cortex renin and AT1R increased significantly in the HS and HS+H groups. Urinary protein was positively correlated with renal renin and AT1R levels. However, in the HS+E and HS+V groups, enalapril and valsartan failed to influence renal renalase expression but abolished the increase in proteinuria, renal cortex renin, and AT1R levels with respect to the HS group. This study indicates that high salt intake reduces renal expression, and renal RAS may be not involved in the regulation of renalase in SD rats fed with high-salt diet. © 2015 The Author(s) Published by S. Karger AG, Basel.

  2. Effects of peripherally and centrally applied ghrelin on the oxidative stress induced by renin angiotensin system in a rat model of renovascular hypertension.

    Science.gov (United States)

    Boshra, Vivian; Abbas, Amr M

    2017-07-26

    Renovascular hypertension (RVH) is a result of renal artery stenosis, which is commonly due to astherosclerosis. In this study, we aimed to clarify the central and peripheral effects of ghrelin on the renin-angiotensin system (RAS) in a rat model of RVH. RVH was induced in rats by partial subdiaphragmatic aortic constriction. Experiment A was designed to assess the central effect of ghrelin via the intracerebroventricular (ICV) injection of ghrelin (5 μg/kg) or losartan (0.01 mg/kg) in RVH rats. Experiment B was designed to assess the peripheral effect of ghrelin via the subcutaneous (SC) injection of ghrelin (150 μg/kg) or losartan (10 mg/kg) for 7 consecutive days. Mean arterial blood pressure (MAP), heart rate, plasma renin activity (PRA), and oxidative stress markers were measured in all rats. In addition, angiotensin II receptor type 1 (AT1R) concentration was measured in the hypothalamus of rats in Experiment B. RVH significantly increased brain AT1R, PRA, as well as the brain and plasma oxidative stress. Either SC or ICV ghrelin or losartan caused a significant decrease in MAP with no change in the heart rate. Central ghrelin or losartan caused a significant decrease in brain AT1R with significant alleviation of the brain oxidative stress. Central ghrelin caused a significant decrease in PRA, whereas central losartan caused a significant increase in PRA. SC ghrelin significantly decreased PRA and plasma oxidative stress, whereas SC losartan significantly increased PRA and decreased plasma oxidative stress. The hypotensive effect of ghrelin is mediated through the amelioration of oxidative stress, which is induced by RAS centrally and peripherally.

  3. Reporter mouse strain provides a novel look at angiotensin type-2 receptor distribution in the central nervous system.

    Science.gov (United States)

    de Kloet, Annette D; Wang, Lei; Ludin, Jacob A; Smith, Justin A; Pioquinto, David J; Hiller, Helmut; Steckelings, U Muscha; Scheuer, Deborah A; Sumners, Colin; Krause, Eric G

    2016-03-01

    Angiotensin-II acts at its type-1 receptor (AT1R) in the brain to regulate body fluid homeostasis, sympathetic outflow and blood pressure. However, the role of the angiotensin type-2 receptor (AT2R) in the neural control of these processes has received far less attention, largely because of limited ability to effectively localize these receptors at a cellular level in the brain. The present studies combine the use of a bacterial artificial chromosome transgenic AT2R-enhanced green fluorescent protein (eGFP) reporter mouse with recent advances in in situ hybridization (ISH) to circumvent this obstacle. Dual immunohistochemistry (IHC)/ISH studies conducted in AT2R-eGFP reporter mice found that eGFP and AT2R mRNA were highly co-localized within the brain. Qualitative analysis of eGFP immunoreactivity in the brain then revealed localization to neurons within nuclei that regulate blood pressure, metabolism, and fluid balance (e.g., NTS and median preoptic nucleus [MnPO]), as well as limbic and cortical areas known to impact stress responding and mood. Subsequently, dual IHC/ISH studies uncovered the phenotype of specific populations of AT2R-eGFP cells. For example, within the NTS, AT2R-eGFP neurons primarily express glutamic acid decarboxylase-1 (80.3 ± 2.8 %), while a smaller subset express vesicular glutamate transporter-2 (18.2 ± 2.9 %) or AT1R (8.7 ± 1.0 %). No co-localization was observed with tyrosine hydroxylase in the NTS. Although AT2R-eGFP neurons were not observed within the paraventricular nucleus (PVN) of the hypothalamus, eGFP immunoreactivity is localized to efferents terminating in the PVN and within GABAergic neurons surrounding this nucleus. These studies demonstrate that central AT2R are positioned to regulate blood pressure, metabolism, and stress responses.

  4. Association of angiotensin-converting enzyme inhibitor therapy and comorbidity in diabetes: results from the Vermont diabetes information system

    Directory of Open Access Journals (Sweden)

    MacLean Charles D

    2008-12-01

    Full Text Available Abstract Background Angiotensin converting enzyme inhibitors (ACE inhibitors reduce peripheral vascular resistance via blockage of angiotensin converting enzyme (ACE. ACE inhibitors are commonly used to treat congestive heart failure and high blood pressure, but other effects have been reported. In this study, we explored the association between ACE inhibitor therapy and the prevalence of comorbid conditions in adults with diabetes Methods We surveyed 1003 adults with diabetes randomly selected from community practices. Patients were interviewed at home and self-reported their personal and clinical characteristics including comorbidity. Current medications were obtained by direct observation of medication containers. We built logistic regression models with the history of comorbidities as the outcome variable and the current use of ACE inhibitors as the primary predictor variable. We adjusted for possible confounding by social (age, sex, alcohol drinking, cigarette smoking and clinical factors (systolic blood pressure, body mass index (BMI, glycosolated hemoglobin (A1C, number of comorbid conditions, and number of prescription medications. Results ACE users reported a history of any cancer (except the non-life-threatening skin cancers less frequently than non-users (10% vs. 15%; odd ratio = 0.59; 95% confidence interval [0.39, 0.89]; P = 0.01; and a history of stomach ulcers or peptic ulcer disease less frequently than non-users (12% vs. 16%, odd ratio = 0.70, [0.49, 1.01], P = 0.06. After correcting for potential confounders, ACE inhibitors remained significantly inversely associated with a personal history of cancer (odds ratio = 0.59, [0.39, 0.89]; P = 0.01 and peptic ulcer disease (odd ratio = 0.68, [0.46, 1.00], P = 0.05. Conclusion ACE inhibitor use is associated with a lower likelihood of a history of cancer and peptic ulcers in patients with diabetes. These findings are limited by the cross sectional study design, self-report of comorbid

  5. Intracellular mediators of potassium-induced aldosterone secretion

    International Nuclear Information System (INIS)

    Ganguly, A.; Chiou, S.; Davis, J.S.

    1990-01-01

    We have investigated the intracellular messengers of potassium in eliciting aldosterone secretion in calf adrenal glomerulosa cells since there were unresolved issues relating to the role of phosphoinositides, cAMP and protein kinases. We observed no evidence of hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP 2 ) in 3 H-inositol labeled alf adrenal cells or increase of cAMP in response to potassium. Addition of calcium channel blocker, nitrendipine after stimulating adrenal glomerulosa cells with potassium, markedly inhibited aldosterone secretion. A calmodulin inhibitor (W-7) produced greater reduction of aldosterone secretion than an inhibitor of protein kinase C (H-7). These results suggest that a rise in cytosolic free calcium concentration through voltage-dependent calcium channel and calmodulin are the critical determinants of aldosterone secretion stimulated by potassium

  6. The role of potassium and other ions in the control of aldosterone synthesis

    International Nuclear Information System (INIS)

    Kenyon, C.J.; Shepherd, R.M.; Fraser, R.; Pediani, J.D.; Elder, H.Y.

    1991-01-01

    Fast and slow K+ efflux components, independently regulated by angiotensin II (AII), have been identified in bovine adrenocortical cells. The authors have further investigated the role of potassium in the control of aldosterone synthesis in two ways. Firstly, isotopic tracers, in conjunction with channel modulators, have been used to study the interrelationship of K+ and Ca2+ in the control of AII-stimulated aldosterone synthesis. Secondly, electron probe X-ray microanalysis (EPXMA) was used to quantify potassium, sodium, chlorine and phosphorous in control and AII-stimulated cells. The effects of verapamil on 43K efflux were measured at two stages during AII stimulation. During the first ten minutes of treatment, when efflux via the fast component predominates, AII and verapamil both slowed efflux and their effects were additive. If verapamil was added later, at the time when efflux by the fast component appeared exhausted and the stimulatory effect of AII on the slow efflux component was apparent, it again slowed efflux. These data suggest that verapamil prevents calcium-gated K+ channels from opening by blocking Ca2+ channels. However, verapamil had no effect on AII-stimulated calcium efflux. In addition to blocking Ca2+ channels, verapamil may directly inhibit potassium efflux. EPXMA showed a bimodal distribution of potassium concentrations in control cells. However, in cells stimulated with AII for five minutes, the mean potassium content was less than in controls and was not bimodally distributed. Sodium content was increased by AII-treatment, chlorine was lowered and phosphorus remained unchanged. The data confirm previous observations that AII inhibits Na+/K+ ATPase activity

  7. Quantitative assessment of the association between the angiotensin-converting enzyme gene insertion/deletion polymorphism and digestive system cancer risk.

    Science.gov (United States)

    Wang, J; Yang, S; Guo, F H; Mao, X; Zhou, H; Dong, Y Q; Wang, Z M; Luo, F

    2015-11-13

    The angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism has been reported to be associated with digestive system cancer; however, the results from previous studies have been conflicting. The present study aimed to investigate the association between the ACE I/D polymorphism and the risk of digestive system cancer using a meta-analysis of previously published studies. Databases were systematically searched to identify relevant studies published prior to December 2014. We estimated the pooled OR with its 95%CI to assess the association. The meta-analysis consisted of thirteen case-control studies that included 2557 patients and 4356 healthy controls. Meta-analysis results based on all the studies showed no significant association between the ACE I/D polymorphism and the risk of digestive system cancer (DD vs II: OR = 0.85, 95%CI = 0.59-1.24; DI vs II: OR = 0.94, 95%CI = 0.78-1.15; dominant model: OR = 0.96, 95%CI = 0.81- 1.15; recessive model: OR = 1.06, 95%CI = 0.76-1.48). Subgroup analyses by race and cancer type did not detect an association between the ACE I/D polymorphism and digestive system cancer risk. However, when the analyses were restricted to smaller studies (N digestive system cancer. Further large and well-designed studies are needed to confirm these conclusions.

  8. Angiotensin type 2 receptor (AT2R) and receptor Mas

    DEFF Research Database (Denmark)

    Villela, Daniel; Leonhardt, Julia; Patel, Neal

    2015-01-01

    The angiotensin type 2 receptor (AT2R) and the receptor Mas are components of the protective arms of the renin-angiotensin system (RAS), i.e. they both mediate tissue protective and regenerative actions. The spectrum of actions of these two receptors and their signalling mechanisms display striking...... the phenomenon of blockade of angiotensin-(1-7) [Ang-(1-7)] actions by AT2R antagonists and vice versa. Such mechanisms may comprise dimerization of the receptors or dimerization-independent mechanisms such as lack of specificity of the receptor ligands used in the experiments or involvement of the Ang-(1...

  9. Angiotensin II disrupts inhibitory avoidance memory retrieval.

    Science.gov (United States)

    Bonini, Juliana S; Bevilaqua, Lia R; Zinn, Carolina G; Kerr, Daniel S; Medina, Jorge H; Izquierdo, Iván; Cammarota, Martín

    2006-08-01

    The brain renin-angiotensin system (RAS) is involved in learning and memory, but the actual role of angiotensin II (A(II)) and its metabolites in this process has been difficult to comprehend. This has been so mainly due to procedural issues, especially the use of multi-trial learning paradigms and the utilization of pre-training intracerebroventricular infusion of RAS-acting compounds. Here, we specifically analyzed the action of A(II) in aversive memory retrieval using a hippocampal-dependent, one-trial, step-down inhibitory avoidance task (IA) in combination with stereotaxically localized intrahippocampal infusion of drugs. Rats bilaterally implanted with infusion cannulae aimed to the CA1 region of the dorsal hippocampus were trained in IA and tested for memory retention 24 h later. We found that when given into CA1 15 min before IA memory retention test, A(II), but not angiotensin IV or angiotensin(1-7) induced a dose-dependent and reversible amnesia without altering locomotor activity, exploratory behavior or anxiety state. The effect of A(II) was blocked in a dose-dependent manner by the A(II)-type 2 receptor (AT(2)) antagonist PD123319 but not by the A(II)-type 1 receptor (AT(1)) antagonist losartan. By themselves, neither PD123319 nor losartan had any effect on memory expression. Our data indicate that intra-CA1 A(II) hinders retrieval of avoidance memory through a process that involves activation of AT(2) receptors.

  10. Evaluation of the effects of various sound pressure levels on the level of serum aldosterone concentration in rats

    Directory of Open Access Journals (Sweden)

    Parvin Nassiri

    2017-01-01

    Full Text Available Introduction: Noise exposure may have anatomical, nonauditory, and auditory influences. Considering nonauditory impacts, noise exposure can cause alterations in the automatic nervous system, including increased pulse rates, heightened blood pressure, and abnormal secretion of hormones. The present study aimed at examining the effect of various sound pressure levels (SPLs on the serum aldosterone level among rats. Materials and Methods: A total of 45 adult male rats with an age range of 3 to 4 months and a weight of 200 ± 50 g were randomly divided into 15 groups of three. Three groups were considered as the control groups and the rest (i.e., 12 groups as the case groups. Rats of the case groups were exposed to SPLs of 85, 95, and 105 dBA. White noise was used as the noise to which the rats were exposed. To measure the level of rats’ serum aldosterone, 3 mL of each rat’s sample blood was directly taken from the heart of anesthetized animals by using syringes. The taken blood samples were put in labeled test tubes that contained anticoagulant Ethylenediaminetetraacetic acid. In the laboratory, the level of aldosterone was assessed through Enzyme-linked immunosorbent assay protocol. The collected data were analyzed by the use of Statistical Package for Social Sciences (SPSS version 18. Results: The results revealed that there was no significant change in the level of rats’ serum aldosterone as a result of exposure to SPLs of 65, 85, and 95 dBA. However, the level of serum aldosterone experienced a remarkable increase after exposure to the SPL of 105 dBA (P < 0.001. Thus, the SPL had a significant impact on the serum aldosterone level (P < 0.001. In contrast, the exposure time and the level of potassium in the used water did not have any measurable influence on the level of serum aldosterone (P = 0.25 and 0.39. Conclusion: The findings of this study demonstrated that serum aldosterone can be used as a biomarker in the face of sound

  11. Release of beta-lipotropin- and beta-endorphin-like material induced by angiotensin in the conscious rat

    NARCIS (Netherlands)

    Beuers, U.; HERTTING, G.; KNEPEL, W.

    1982-01-01

    1 The influence of the renin-angiotensin system on plasma beta-endorphin-like immunoreactivity (beta-EI) was investigated in the conscious rat by use of a radioimmunoassay for beta-endorphin without prior extraction.2 Intravenous infusion of angiotensin I, II or (des-1-Asp)angiotensin II

  12. Circadian as well as circannual rhythms of circulating aldosterone have decreased amplitude in aging women.

    Science.gov (United States)

    Cugini, P; Scavo, D; Centanni, M; Halberg, F; Haus, E; Lakatua, D; Schramm, A; Pusch, H J; Franke, H; Kawasaky, T

    1983-02-01

    Age differences in the characteristics of the circadian rhythm in circulating radioimmunoassayable aldosterone were studied on nine 20 to 26 year-old and ten 70 to 78 year-old women and ten 23 to 26 year old and ten 70 to 80 year old men in Würzburg, West Germany. These diurnally active-nocturnally resting subjects were sampled every 3 hours for 15 hours. A classical analysis of variance and a multivariate analysis of rhythm characteristics revealed major effects of age exerted on the circadian aldosterone amplitude in women (p = 0.003) but not in concomitantly sampled men. These observations complement the study of circadian and circannual rhythms in 8 young adults (15-21 years), 10 mature adults (29-36 years) and 10 post-menopausal (44-59 years) North American women, sampled at 100 minute intervals for 24 hours, once in each season, and document that the adrenocortical aldosterone-producing system remains rhythmic with at least two frequencies up to the late decades of human life, although in women it may be characterized by a reduction in the extent of spectral change after 70 years of age.

  13. Molecular and cellular mechanisms of aldosterone producing adenoma development

    Directory of Open Access Journals (Sweden)

    Sheerazed eBoulkroun

    2015-06-01

    Full Text Available Primary aldosteronism (PA is the most common form of secondary hypertension with an estimated prevalence of ~10% in referred patients. PA occurs as a result of a dysregulation of the normal mechanisms controlling adrenal aldosterone production. It is characterized by hypertension with low plasma renin and elevated aldosterone and often associated with hypokalemia. The two major causes of PA are unilateral aldosterone producing adenoma (APA and bilateral adrenal hyperplasia, accounting together for ~95% of cases. In addition to the well-characterized effect of excess mineralocorticoids on blood pressure, high levels of aldosterone also have cardiovascular, renal and metabolic consequences. Hence, long-term consequences of PA include increased risk of coronary artery disease, myocardial infarction, heart failure and atrial fibrillation. Despite recent progress in the management of patients with PA, critical issues related to diagnosis, subtype differentiation and treatment of non-surgically correctable forms still persist. A better understanding of the pathogenic mechanisms of the disease should lead to the identification of more reliable diagnostic and prognostic biomarkers for a more sensitive and specific screening and new therapeutic options. In this review we will summarize our current knowledge on the molecular and cellular mechanisms of APA development. On one hand, we will discuss how various animal models have improved our understanding of the pathophysiology of excess aldosterone production. On the other hand, we will summarize the major advances made during the last few years in the genetics of APA due to transcriptomic studies and whole exome sequencing. The identification of recurrent and somatic mutations in genes coding for ion channels (KCNJ5 and CACNA1D and ATPases (ATP1A1 and ATP2B3 allowed highlighting the central role of calcium signaling in autonomous aldosterone production by the adrenal.

  14. Oxidative stress in patients affected by primary aldosteronism.

    Science.gov (United States)

    Petramala, Luigi; Pignatelli, Pasquale; Carnevale, Roberto; Zinnamosca, Laura; Marinelli, Cristiano; Settevendemmie, Amina; Concistrè, Antonio; Tonnarini, Gianfranco; De Toma, Giorgio; Violi, Francesco; Letizia, Claudio

    2014-10-01

    Primary aldosteronism, an important form of secondary hypertension, is associated with significant increase of cardiovascular risk (ischaemic heart, cerebrovascular events, arrhythmias) (relative risk 4.6). The specific treatment of primary aldosteronism significantly reduces cardiovascular risk. In addition to high blood pressure values and direct action of aldosterone, new mechanisms such as increased oxidative stress are involved in the development of organ damage, metabolic, endothelial and coagulation complications. The aim of the study was to evaluate parameters of oxidative stress in 38 patients (21 men, 17 women, mean age 53.3 ± 4.7 years) with primary aldosteronism [11 aldosterone-producing adenoma (APA) (4 men, 7 women, mean age 50.2 ± 4.5 years) and 27 idiopathic adrenal hyperplasia (IHA) (17 men, 10 women, mean age 54.5 ± 5.3 years)] at diagnosis and after specific treatment (surgical or pharmacological), with respect to 50 patients with essential hypertension (26 men, 24 women, mean age 49 ± 7.4 years) and 50 healthy individuals (28 men, 22 women, mean age 48.7 ± 4.4 years). Patients with primary aldosteronism showed significant increase of NADPH oxidase (Nox2-dp) plasma levels and urinary isoprostanes (34.9 ± 4.3 μg/dl and 216.3 ± 15.7 ng/mg, respectively; P oxidative stress in primary aldosteronism, characterized by increased serum levels of Nox2-dp and urinary excretion of isoprostanes. After APA removal with laparoscopic adrenalectomy, we found reduction of serum Nox2-dp and urinary isoprostanes.

  15. Effect of ipsilateral ureteric obstruction on contralateral kidney and role of renin angiotensin system blockade on renal recovery in experimentally induced unilateral ureteric obstruction

    Directory of Open Access Journals (Sweden)

    Shasanka S Panda

    2013-01-01

    Full Text Available Aims: To study, the effects of ipsilateral ureteric obstruction on contralateral kidney and the role of renin angiotensin system (RAS blockade on renal recovery in experimentally induced unilateral ureteric obstruction. Materials and Methods: Unilateral upper ureteric obstruction was created in 96 adult Wistar rats that were reversed after pre-determined intervals. Losartan and Enalapril were given to different subgroups of rats following relief of obstruction. Results: The severity of dilatation on the contralateral kidney varied with duration of ipsilateral obstruction longer the duration more severe the dilatation. There is direct correlation between renal parenchymal damage, pelvi-ureteric junction (PUJ fibrosis, inflammation and severity of pelvi-calyceal system dilatation of contralateral kidney with duration of ipsilateral PUJ obstruction. Conclusions: Considerable injury is also inflicted to the contralateral normal kidney while ipsilateral kidney remains obstructed. Use of RAS blocking drugs has been found to significantly improve renal recovery on the contralateral kidney. It can, thus, be postulated that contralateral renal parenchymal injury was mediated through activation of RAS.

  16. Interactive effects of apelin, renin-angiotensin system and nitric oxide in treatment of obesity-induced type 2 diabetes mellitus in male albino rats.

    Science.gov (United States)

    Sabry, Maha Mohamed; Mahmoud, Manal Moustafa; Shoukry, Heba Samy; Rashed, Laila; Kamar, Samaa Samir; Ahmed, Mona Mohamed

    2018-03-22

    Apelin and its receptor (APJ) are involved in the regulation of a variety of pathophysiological processes. We studied the effect of apelin treatment on obesity-induced type 2 diabetes mellitus (T2DM) and possible interaction between apelin/APJ system and renin-angiotensin system (RAS). Forty eight male albino rats were divided into two groups: control group and diabetic group. Diabetic group was subdivided into: control diabetic, apelin-treated, apelin + losartan-treated, apelin + l-NAME-treated and losartan-treated diabetic subgroup. Administration of apelin-13 yielded an improvement of IR, dyslipidaemia, inflammation, oxidative stress with significant decrease in AT1R gene expression and significant increase in ACE2 gene expression in adipose tissues. Losartan + apelin yielded a further significant decrease in ATR1 gene expression, glycaemic indices, serum TGs and TPA versus Apelin only. Adding l-NAME in subgroup (2D) reversed the effect of apelin. We suggested that the beneficial effect of Apelin is mainly mediated by NO-activated pathway and/or ACE2/Ang (1-7) dependent pathway.

  17. Clinical Characteristics of Aldosterone- and Cortisol-Coproducing Adrenal Adenoma in Primary Aldosteronism

    Directory of Open Access Journals (Sweden)

    Lu Tang

    2018-01-01

    Full Text Available Aldosterone- and cortisol-coproducing adrenal adenoma (A/CPA cases have been observed in patients with primary aldosteronism (PA. This study investigated the incidence, clinical characteristics, and molecular biological features of patients with A/CPAs. We retrospectively identified 22 A/CPA patients from 555 PA patients who visited the Chinese People’s Liberation Army General Hospital between 2004 and 2015. Analysis of clinical parameters revealed that patients with A/CPAs had larger tumors than those with pure APAs (P<0.05. Moreover, they had higher proportions of cardiovascular complications, glucose intolerance/diabetes, and osteopenia/osteoporosis compared to the pure APA patients (P<0.001. In the molecular biological findings, quantitative real-time PCR analysis revealed similar CYP11B1 and CYP17A1 mRNA expressions in resected A/CPA specimens and in pure APA specimens. Western blot and immunochemical analyses showed CYP11B1, CYP11B2, and CYP17A1 expressions in both A/CPAs and pure APAs. Seventeen cases with KCNJ5 mutations were detected among the 22 A/CPA DNA samples, but no PRKACA or other causative mutations were observed. Each patient improved following adrenalectomy. In conclusion, A/CPAs were not rare among PA patients. These patients associated with high incidences of cardiovascular events and metabolic disorders. Screening for excess cortisol secretion is necessary for PA patients.

  18. LmrBPP9: A synthetic bradykinin-potentiating peptide from Lachesis muta rhombeata venom that inhibits the angiotensin-converting enzyme activity in vitro and reduces the blood pressure of hypertensive rats.

    Science.gov (United States)

    Pinheiro-Júnior, Ernesto Lopes; Boldrini-França, Johara; de Campos Araújo, Luciana Mattoso Pires; Santos-Filho, Norival Alves; Bendhack, Lusiane Maria; Cilli, Eduardo Maffud; Arantes, Eliane Candiani

    2018-04-01

    Bradykinin-potentiating peptides (BPPs) are an important group of toxins present in Lachesis muta rhombeata venom. They act directly at renin-angiotensin-aldosterone system, through the inhibition of angiotensin-converting enzyme (ACE). This action may contribute to the hypotensive shock observed during the envenoming by this species. Thus, the main goal of this study was the solid-phase synthesis of a BPP found in L. m. rhombeata venom and its in vitro and in vivo characterization in relation to ACE inhibition and hypotensive activity, respectively. The LmrBPP9 peptide was synthesized using an automated solid-phase peptide synthesizer and purified by reversed-phase fast protein liquid chromatography (FPLC). The in vitro IC50 of the synthetic peptide is 4.25 ± 0.10 μM, showing a great capacity of ACE inhibition. The in vivo studies showed that LmrBPP9 induces blood pressure reduction, both in normotensive and hypertensive rats, being more pronounced in the last ones. These results agree with the in vitro results, showing that the synthetic peptide LmrBPP9 is a potential molecule to the development of a new antihypertensive drug. Copyright © 2018 Elsevier Inc. All rights reserved.

  19. Rate of angiotensin II generation within the human pulmonary vascular bed

    DEFF Research Database (Denmark)

    Giese, Jacob; Kappelgaard, A M; Tønnesen, K H

    1980-01-01

    concentration in mixed venous blood and in systemic arterial blood. The pulmonary angiotensin II production rate was measured in fourteen patients. This parameter was linearly correlated with plasma renin concentration in systemic arterial blood. The plasma clearance of angiotensin II across the systemic......Plasma angiotensin II concentration gradients across the pulmonary vascular bed were measured during diagnostic renal venous/right heart catheterization in twenty-seven hypertensive patients with renal or renovascular disease. There was a linear correlation between the plasma angiotensin II...

  20. Rate of angiotensin II generation within the human pulmonary vascular bed

    DEFF Research Database (Denmark)

    Giese, Jacob; Kappelgaard, A M; Tønnesen, K H

    1980-01-01

    Plasma angiotensin II concentration gradients across the pulmonary vascular bed were measured during diagnostic renal venous/right heart catheterization in twenty-seven hypertensive patients with renal or renovascular disease. There was a linear correlation between the plasma angiotensin II...... concentration in mixed venous blood and in systemic arterial blood. The pulmonary angiotensin II production rate was measured in fourteen patients. This parameter was linearly correlated with plasma renin concentration in systemic arterial blood. The plasma clearance of angiotensin II across the systemic...

  1. Aldosterone and Its Blockade: A Cardiovascular and Renal Perspective

    Directory of Open Access Journals (Sweden)

    V. Lahera

    2006-01-01

    Full Text Available Aldosterone not only contributes to salt and water homeostasis, but also exerts direct cardiovascular and renal effects. Numerous experimental and clinical studies indicate that aldosterone participate in cardiac alterations associated with hypertension, heart failure, diabetes and other pathological entities. It is important to mention that dietary salt is a key factor in aldosterone-mediated cardiovascular damage, since damage was moreevident in animals on a high-salt diet than animals on a low salt diet. A pathophysiological action of aldosterone involves development of extracellular matrix and fibrosis, inflammation, stimulation of reactive oxygen species production, endothelial dysfunction, cell growth and proliferation. Many studies showed local extra-adrenal production of aldosterone in brain blood vessel, and the heart, which contribute in an important manner to the pathological actions of this mineralocorticoid.Several studies such as RALES, EPHESUS, 4E and others, recently showed that mineralocorticoid-receptor (MR antagonists, alone or in combination with ACE inhibitors or ARBs, reduced the risk of progressive target organ damage and hospitalization in patients with hypertension and heart failure. These clinical benefits support the therapeutic usefulness of MR antagonists.

  2. The studies on aldosterone secretion rate by radioimmunoassay

    International Nuclear Information System (INIS)

    Takenouchi, Takahiko

    1974-01-01

    The aldosterone secretion rate was measured by radioimmunoassay in 12 normal subjects and 47 hypertensive patients. The values ranged from 25.0 to 60.2 ng/day with a mean of 39.6+-10.7 (S.D.) in 8 normal males and from 30.2 to 85.4 ng/day with a mean of 62.6+-26.8 (S.D.) in 4 normal females. The mean value in 21 cases with benign essential hypertension was found to be within normal range. No significant difference was found in the aldosterone secretion rate between the group of benign essential hypertension with suppressed renin activity and with nonsuppressed renin activity. Metabolic clearance rate in benign essential hypertension was observed to be within normal range. The aldosterone secretion rate in a few cases of benign essential hypertension failed to increase normally in response to sodium restriction (<50 mEq/day). The values in 11 cases of primary aldosteronism were found to be clearly higher, when compared with the values of normal subjects and subjects with benign essential hypertension. High values were found in patients suffering from malignant hypertension and in 3 with unilateral renal artery stenosis. The values in cases of bilateral renal artery stenosis, of pheochromocytoma, and of acromegaly with hypertension were within normal range. Low values in the aldosterone secretion rate were found in 3 cases each of 17α-hydroxylase deficiency and Cushing's syndrome. (JPN)

  3. Effects of Treating Primary Aldosteronism on Renal Function.

    Science.gov (United States)

    Kramers, Bart J; Kramers, Cornelis; Lenders, Jacques W M; Deinum, Jaap

    2017-03-01

    Longstanding primary aldosteronism (PA) has deleterious effects on renal function, often masked until treatment (adrenalectomy or spironolactone) is initiated. It has been suggested that PA causes relative glomerular hyperfiltration, explaining the decline in estimated glomerular filtration rate (eGFR) after treatment. In this retrospective study, the authors retrieved the clinical characteristics and eGFR of 134 PA patients before and 6 months after treatment. Using multiple regression analysis, the predictors for eGFR decline and the predictors of ultimately attained renal function in 113 patients was assessed. eGFR declined by 15.3±14.2 (range 19-63) mL/min, independent predictors were pretreatment plasma aldosterone, eGFR, plasma renin, and plasma potassium. Independent predictors of ultimately attained eGFR after treatment were pretreatment plasma aldosterone, age, eGFR, and plasma potassium. Our findings lend support to the hypothesis that higher aldosterone levels cause relative glomerular hyperfiltration. The severity of pretreatment aldosterone excess is the most important risk factor for renal function decline. ©2016 Wiley Periodicals, Inc.

  4. Prenatal inflammation-induced NF-κB dyshomeostasis contributes to renin-angiotensin system over-activity resulting in prenatally programmed hypertension in offspring

    Science.gov (United States)

    Deng, Youcai; Deng, Yafei; He, Xiaoyan; Chu, Jianhong; Zhou, Jianzhi; Zhang, Qi; Guo, Wei; Huang, Pei; Guan, Xiao; Tang, Yuan; Wei, Yanling; Zhao, Shanyu; Zhang, Xingxing; Wei, Chiming; Namaka, Michael; Yi, Ping; Yu, Jianhua; Li, Xiaohui

    2016-01-01

    Studies involving the use of prenatally programmed hypertension have been shown to potentially contribute to prevention of essential hypertension (EH). Our previous research has demonstrated that prenatal inflammatory stimulation leads to offspring’s aortic dysfunction and hypertension in pregnant Sprague-Dawley rats challenged with lipopolysaccharide (LPS). The present study found that prenatal LPS exposure led to NF-κB dyshomeostasis from fetus to adult, which was characterized by PI3K-Akt activation mediated degradation of IκBα protein and impaired NF-κB self-negative feedback loop mediated less newly synthesis of IκBα mRNA in thoracic aortas (gestational day 20, postnatal week 7 and 16). Prenatal or postnatal exposure of the IκBα degradation inhibitor, pyrollidine dithiocarbamate, effectively blocked NF-κB activation, endothelium dysfunction, and renin-angiotensin system (RAS) over-activity in thoracic aortas, resulting in reduced blood pressure in offspring that received prenatal exposure to LPS. Surprisingly, NF-κB dyshomeostasis and RAS over-activity were only found in thoracic aortas but not in superior mesenteric arteries. Collectively, our data demonstrate that the early life NF-κB dyshomeostasis induced by prenatal inflammatory exposure plays an essential role in the development of EH through triggering RAS over-activity. We conclude that early life NF-κB dyshomeostasis is a key predictor of EH, and thus, NF-κB inhibition represents an effective interventional strategy for EH prevention. PMID:26877256

  5. Prenatal inflammation-induced NF-κB dyshomeostasis contributes to renin-angiotensin system over-activity resulting in prenatally programmed hypertension in offspring.

    Science.gov (United States)

    Deng, Youcai; Deng, Yafei; He, Xiaoyan; Chu, Jianhong; Zhou, Jianzhi; Zhang, Qi; Guo, Wei; Huang, Pei; Guan, Xiao; Tang, Yuan; Wei, Yanling; Zhao, Shanyu; Zhang, Xingxing; Wei, Chiming; Namaka, Michael; Yi, Ping; Yu, Jianhua; Li, Xiaohui

    2016-02-15

    Studies involving the use of prenatally programmed hypertension have been shown to potentially contribute to prevention of essential hypertension (EH). Our previous research has demonstrated that prenatal inflammatory stimulation leads to offspring's aortic dysfunction and hypertension in pregnant Sprague-Dawley rats challenged with lipopolysaccharide (LPS). The present study found that prenatal LPS exposure led to NF-κB dyshomeostasis from fetus to adult, which was characterized by PI3K-Akt activation mediated degradation of IκBα protein and impaired NF-κB self-negative feedback loop mediated less newly synthesis of IκBα mRNA in thoracic aortas (gestational day 20, postnatal week 7 and 16). Prenatal or postnatal exposure of the IκBα degradation inhibitor, pyrollidine dithiocarbamate, effectively blocked NF-κB activation, endothelium dysfunction, and renin-angiotensin system (RAS) over-activity in thoracic aortas, resulting in reduced blood pressure in offspring that received prenatal exposure to LPS. Surprisingly, NF-κB dyshomeostasis and RAS over-activity were only found in thoracic aortas but not in superior mesenteric arteries. Collectively, our data demonstrate that the early life NF-κB dyshomeostasis induced by prenatal inflammatory exposure plays an essential role in the development of EH through triggering RAS over-activity. We conclude that early life NF-κB dyshomeostasis is a key predictor of EH, and thus, NF-κB inhibition represents an effective interventional strategy for EH prevention.

  6. Cognitive performance, symptoms and counter-regulation during hypoglycaemia in patients with type 1 diabetes and high or low renin-angiotensin system activity.

    Science.gov (United States)

    Høi-Hansen, Thomas; Pedersen-Bjergaard, Ulrik; Andersen, Rikke Due; Kristensen, Peter Lommer; Thomsen, Carsten; Kjaer, Troels; Høgenhaven, Hans; Smed, Annelise; Holst, Jens Juul; Dela, Flemming; Boomsma, Frans; Thorsteinsson, Birger

    2009-12-01

    High basal renin-angiotensin system (RAS) activity is associated with increased risk of severe hypoglycaemia in type 1 diabetes. We tested whether this might be explained by more pronounced cognitive dysfunction during hypoglycaemia in patients with high RAS activity than in patients with low RAS activity. Nine patients with type 1 diabetes and high and nine with low RAS activity were subjected to hypoglycaemia and euglycaemia in a cross-over study using an intravenous insulin infusion protocol. Cognitive function, electroencephalography, auditory evoked potentials and hypoglycaemic symptoms were recorded. At a hypoglycaemic nadir of 2.2 (SD 0.3) mmol/L the high RAS group displayed significant deterioration in cognitive performance during hypoglycaemia in the three most complex reaction time tasks. In the low RAS group, hypoglycaemia led to cognitive dysfunction in only one reaction time task. The high RAS group reported lower symptom scores during hypoglycaemia than the low RAS group, suggesting poorer hypoglycaemia awareness. High RAS activity is associated with increased cognitive dysfunction and blunted symptoms during mild hypoglycaemia compared to low RAS activity. This may explain why high RAS activity is a risk factor for severe hypoglycaemia in type 1 diabetes.

  7. Anti-stress and nootropic activity of drugs affecting the renin-angiotensin system in rats based on indirect biochemical evidence.

    Science.gov (United States)

    Anil Kumar, K V; Nagwar, Shrasti; Thyloor, Rama; Satyanarayana, Sreemantula

    2015-12-01

    Various stress hormones are responsible for bringing out stress-related changes and are implicated in learning and memory processes. The extensive clinical experience of angiotensin receptor blockers (ARBs) and direct renin inhibitor as antihypertensive agents provides anecdotal evidence of improvements in cognition. The neurochemical basis underlying the anti-stress and nootropic effects are unclear. This study was aimed to determine the effects of aliskiren, valsartan and their combination on the neuromediators of the central nervous system (CNS) and periphery as well as on cognitive function. Groups of rats were subjected to a forced swim stress for one hour after daily treatment with aliskiren, valsartan and their combination. The 24 h urinary excretion of vanillylmandellic acid (VMA), 5-hydroxyindoleacetic acid (5-HIAA), 6-β-hydroxycortisol (6-β-OH) cortisol and homovanillic acid (HVA) was determined in all groups under normal and stressed conditions. Nootropic activity was studied using cook's pole climbing apparatus and acetylcholinesterase (AChE) inhibitory activity by Ellman's method. Administration of aliskiren (10 mg/kg), valsartan (20 mg/kg) and their combination at a dose of 5 and 10 mg/kg respectively reduced the urinary metabolite levels. Further, all drugs showed significant improvement in scopolamine-impaired performance and produced inhibition of the AChE enzyme. The present study provides scientific support for the anti-stress and nootropic activities of aliskiren, valsartan and their combination. © The Author(s) 2014.

  8. Early renin-angiotensin system intervention is more beneficial than late intervention in delaying end-stage renal disease in patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Schievink, B; Kröpelin, T; Mulder, S

    2016-01-01

    AIMS: To develop and validate a model to simulate progression of diabetic kidney disease (DKD) from early onset until end-stage renal disease (ESRD), and to assess the effect of renin-angiotensin system (RAS) intervention in early, intermediate and advanced stages of DKD. METHODS: We used data from......, intermediate and advanced stage of disease, whose mean age was 60 years and who received placebo, the median time to ESRD was 21.4, 10.8 and 4.7 years, respectively. RAS intervention delayed the predicted time to ESRD by 4.2, 3.6 and 1.4 years, respectively. The benefit of early RAS intervention was more...... pronounced in younger patients; for example, for patients with a mean age of 45 years, RAS intervention at early, intermediate or advanced stage delayed ESRD by 5.9, 4.0 and 1.1 years versus placebo. CONCLUSIONS: RAS intervention early in the course of proteinuric DKD is more beneficial than late...

  9. Bilateral Renal Denervation Ameliorates Isoproterenol-Induced Heart Failure through Downregulation of the Brain Renin-Angiotensin System and Inflammation in Rat

    Directory of Open Access Journals (Sweden)

    Jian-Dong Li

    2016-01-01

    Full Text Available Heart failure (HF is characterized by cardiac dysfunction along with autonomic unbalance that is associated with increased renin-angiotensin system (RAS activity and elevated levels of proinflammatory cytokines (PICs. Renal denervation (RD has been shown to improve cardiac function in HF, but the protective mechanisms remain unclear. The present study tested the hypothesis that RD ameliorates isoproterenol- (ISO- induced HF through regulation of brain RAS and PICs. Chronic ISO infusion resulted in remarked decrease in blood pressure (BP and increase in heart rate and cardiac dysfunction, which was accompanied by increased BP variability and decreased baroreflex sensitivity and HR variability. Most of these adverse effects of ISO on cardiac and autonomic function were reversed by RD. Furthermore, ISO upregulated mRNA and protein expressions of several components of the RAS and PICs in the lamina terminalis and hypothalamic paraventricular nucleus, two forebrain nuclei involved in cardiovascular regulations. RD significantly inhibited the upregulation of these genes. Either intracerebroventricular AT1-R antagonist, irbesartan, or TNF-α inhibitor, etanercept, mimicked the beneficial actions of RD in the ISO-induced HF. The results suggest that the RD restores autonomic balance and ameliorates ISO-induced HF and that the downregulated RAS and PICs in the brain contribute to these beneficial effects of RD.

  10. Endothelin A receptor antagonism in experimental congestive heart failure results in augmentation of the renin-angiotensin system and sustained sodium retention.

    Science.gov (United States)

    Schirger, John A; Chen, Horng H; Jougasaki, Michihisa; Lisy, Ondrej; Boerrigter, Guido; Cataliotti, Alessandro; Burnett, John C

    2004-01-20

    While both the endothelin-1 (ET-1) and renin-angiotensin systems (RAS) are activated in congestive heart failure (CHF), the temporal sequence of this activation remains unclear. Understanding this pattern of neurohumoral activation may aid in understanding the significance of ET-1 in CHF and provide strategies for ET-1 antagonism. Although acute endothelin (ET) receptor antagonism improves systemic hemodynamics in CHF, clinical trials with chronic ET receptor antagonism report worsening CHF symptoms. In a canine model of progressive left ventricular dysfunction, we demonstrated activation of myocardial and plasma ET-1 without activation of the RAS during transition to overt CHF, suggesting that ET-1 contributes to this transition. We next evaluated the effects of chronic oral ET-A receptor antagonism on neurohumoral function, renal hemodynamics, and sodium excretion in pacing-induced CHF. After 7 days of treatment (n=7) with ET-A receptor antagonism (with LU135252), sodium excretion did not improve in treated versus untreated CHF (n=6). Furthermore, both plasma renin activity and plasma ET-1 increased with ET-A receptor blockade. Activation of the myocardial and plasma ET-1 systems precedes activation of the myocardial and plasma RAS in CHF. ET-A receptor antagonism in experimental CHF further activates the RAS without improving sodium excretion. These findings suggest an important role for ET-1 in the progression of CHF and a potential mechanism for the exacerbation of CHF symptoms observed in clinical trials with chronic ET receptor antagonism. Further studies with combined modulation of the ET and other neurohumoral systems in CHF are required.

  11. Myocardial ultrasonic backscatter in hypertension: relation to aldosterone and endothelin.

    Science.gov (United States)

    Kozàkovà, Michaela; Buralli, Simona; Palombo, Carlo; Bernini, Giampaolo; Moretti, Angelica; Favilla, Stefania; Taddei, Stefano; Salvetti, Antonio

    2003-02-01

    A disproportionate accumulation of fibrillar collagen is a characteristic feature of hypertensive heart disease, but the extent of myocardial fibrosis may differ in different models of hypertension. In experimental studies, aldosterone and endothelins emerge as important determinants of myocardial fibrosis. Changes in myocardial extracellular matrix and collagen deposition can be estimated noninvasively by analysis of the ultrasonic backscatter signal, which arises from tissue heterogeneity within the myocardium and describes myocardial texture. This study was designed to investigate the relations between myocardial integrated backscatter and circulating aldosterone and immunoreactive endothelin in human hypertension. The study population consisted of 56 subjects: 14 healthy normotensive volunteers and 42 hypertensive patients (14 with primary aldosteronism, 7 with renovascular hypertension, and 21 with essential hypertension). The patients with essential and secondary hypertension were matched for age, gender, body mass index, and blood pressure. Myocardial integrated backscatter at diastole was 19.8+/-2.0 and 20.8+/-2.9 decibels in normotensive control subjects and patients with essential hypertension and significantly higher in patients with primary aldosteronism (27.4+/-3.8 decibels, P<0.01) and renovascular hypertension (26.8+/-4.8 decibels, P<0.01). In the population as a whole, as well as in the hypertensive subpopulation, myocardial integrated backscatter was directly related to plasma aldosterone (r=0.73 and 0.71, P<0.01 for both) and immunoreactive endothelin (r=0.60 and 0.56, P<0.01 for both). The data of this study suggest that in human hypertension, circulating aldosterone and immunoreactive endothelin may induce alterations in left ventricular myocardial texture, possibly related to increased myocardial collagen content.

  12. Changes of Aldosterone Secretion Rate Following Furosemide Administration in Normotensive Subjects with High Sodium Intake

    International Nuclear Information System (INIS)

    Sung, Ho Kyung; Ryu, Yong Wun; Koh, Joo Hwan

    1976-01-01

    Marked augmentation of urinary aldosterone excretion following furosemide administration was observed in previous experiment. In this study, author measured the changes of aldosterone secretion after furosemide administration in normotensive young volunteers with high sodium intake. After intravenous injection of 1.2- 3 H-aldosterone, urine samples were collected in course of time until 24 hours after the injection. Furosemide administration was done at 30 minutes prior to aldosterone injection. Specific activities of 3H-aldosterone during and after diuresis were measured and aldosterone secretion rates were calculated dividing the doses by specific activities. Results were as followed. 1) Furosemide resulted in a marked increase in urinary aldosterone excretion. 2) Furosemide lead to an increase in both sodium and potassium excretion. 3) Aldosterone secretion rate was also increase d during furosemide diuresis, but the rate was smaller than that of urinary excretion. 4) Continuous modest increase in aldosterone secretion rate was shown after diuresis and total excess amount of aldosterone secretion for 24 hrs was equivalent to the amount of aldosterone excretion produced by diruesis. 5) Abrupt marked loss of circulating aldosterone produced by diuresis was supplemented by long lasting increase in secretion for over twenty four hours.

  13. Chronic infusion of enalaprilat into hypothalamic paraventricular nucleus attenuates angiotensin II-induced hypertension and cardiac hypertrophy by restoring neurotransmitters and cytokines

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Yu-Ming, E-mail: ykang@mail.xjtu.edu.cn [Department of Physiology and Pathophysiology, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University School of Medicine, Xi' an 710061 (China); Zhang, Dong-Mei [Department of Physiology, Dalian Medical University, Dalian 116044 (China); Yu, Xiao-Jing; Yang, Qing; Qi, Jie; Su, Qing [Department of Physiology and Pathophysiology, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University School of Medicine, Xi' an 710061 (China); Suo, Yu-Ping [Department of Obstetrics and Gynecology, Shanxi Provincial People' s Hospital, Taiyuan 030012 (China); Yue, Li-Ying [Department of Physiology and Pathophysiology, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University School of Medicine, Xi' an 710061 (China); Zhu, Guo-Qing [Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing 210029 (China); Qin, Da-Nian, E-mail: dnqin@stu.edu.cn [Department of Physiology, Shantou University Medical College, Shantou 515041 (China)

    2014-02-01

    The renin–angiotensin system (RAS) in the brain is involved in the pathogenesis of hypertension. We hypothesized that inhibition of angiotensin-converting enzyme (ACE) in the hypothalamic paraventricular nucleus (PVN) attenuates angiotensin II (ANG II)-induced hypertension via restoring neurotransmitters and cytokines. Rats underwent subcutaneous infusions of ANG II or saline and bilateral PVN infusions of ACE inhibitor enalaprilat (ENL, 2.5 μg/h) or vehicle for 4 weeks. ANG II infusion resulted in higher mean arterial pressure and cardiac hypertrophy as indicated by increased whole heart weight/body weight ratio, whole heart weight/tibia length ratio, left ventricular weight/tibia length ratio, and mRNA expressions of cardiac atrial natriuretic peptide and beta-myosin heavy chain. These ANG II-infused rats had higher PVN levels of glutamate, norepinephrine, tyrosine hydroxylase, pro-inflammatory cytokines (PICs) and the chemokine monocyte chemoattractant protein-1, and lower PVN levels of gamma-aminobutyric acid, interleukin (IL)-10 and the 67-kDa isoform of glutamate decarboxylase (GAD67), and higher plasma levels of PICs, norepinephrine and aldosterone, and lower plasma IL-10, and higher renal sympathetic nerve activity. However, PVN treatment with ENL attenuated these changes. PVN microinjection of ANG II induced increases in IL-1β and IL-6, and a decrease in IL-10 in the PVN, and pretreatment with angiotensin II type 1 receptor (AT1-R) antagonist losartan attenuated these changes. These findings suggest that ANG II infusion induces an imbalance between excitatory and inhibitory neurotransmitters and an imbalance between pro- and anti-inflammatory cytokines in the PVN, and PVN inhibition of the RAS restores neurotransmitters and cytokines in the PVN, thereby attenuating ANG II-induced hypertension and cardiac hypertrophy. - Highlights: • Chronic ANG II infusion results in sympathetic hyperactivity and cardiac hypertrophy. • PVN inhibition of ACE

  14. Chronic infusion of enalaprilat into hypothalamic paraventricular nucleus attenuates angiotensin II-induced hypertension and cardiac hypertrophy by restoring neurotransmitters and cytokines

    International Nuclear Information System (INIS)

    Kang, Yu-Ming; Zhang, Dong-Mei; Yu, Xiao-Jing; Yang, Qing; Qi, Jie; Su, Qing; Suo, Yu-Ping; Yue, Li-Ying; Zhu, Guo-Qing; Qin, Da-Nian

    2014-01-01

    The renin–angiotensin system (RAS) in the brain is involved in the pathogenesis of hypertension. We hypothesized that inhibition of angiotensin-converting enzyme (ACE) in the hypothalamic paraventricular nucleus (PVN) attenuates angiotensin II (ANG II)-induced hypertension via restoring neurotransmitters and cytokines. Rats underwent subcutaneous infusions of ANG II or saline and bilateral PVN infusions of ACE inhibitor enalaprilat (ENL, 2.5 μg/h) or vehicle for 4 weeks. ANG II infusion resulted in higher mean arterial pressure and cardiac hypertrophy as indicated by increased whole heart weight/body weight ratio, whole heart weight/tibia length ratio, left ventricular weight/tibia length ratio, and mRNA expressions of cardiac atrial natriuretic peptide and beta-myosin heavy chain. These ANG II-infused rats had higher PVN levels of glutamate, norepinephrine, tyrosine hydroxylase, pro-inflammatory cytokines (PICs) and the chemokine monocyte chemoattractant protein-1, and lower PVN levels of gamma-aminobutyric acid, interleukin (IL)-10 and the 67-kDa isoform of glutamate decarboxylase (GAD67), and higher plasma levels of PICs, norepinephrine and aldosterone, and lower plasma IL-10, and higher renal sympathetic nerve activity. However, PVN treatment with ENL attenuated these changes. PVN microinjection of ANG II induced increases in IL-1β and IL-6, and a decrease in IL-10 in the PVN, and pretreatment with angiotensin II type 1 receptor (AT1-R) antagonist losartan attenuated these changes. These findings suggest that ANG II infusion induces an imbalance between excitatory and inhibitory neurotransmitters and an imbalance between pro- and anti-inflammatory cytokines in the PVN, and PVN inhibition of the RAS restores neurotransmitters and cytokines in the PVN, thereby attenuating ANG II-induced hypertension and cardiac hypertrophy. - Highlights: • Chronic ANG II infusion results in sympathetic hyperactivity and cardiac hypertrophy. • PVN inhibition of ACE

  15. ANGIOTENSIN II AND MYOCARDIAL INFARCTION

    Directory of Open Access Journals (Sweden)

    O. P. Shevchenko

    2008-01-01

    Full Text Available The role of angiotensin II in pathogenesis of cardiovascular diseases is discussed. Angiotensin II participates in development of acute myocardial infarction (MI in patients with atherosclerosis. It contributes to inflammation of vessel intimae, oxidative stress, cells apoptosis, matrix remodeling, has pro-thrombosis action, promotes MI expansion and post-MI remodeling. Angiotensin converting enzyme (ACE inhibitors reduce mortality and improve prognosis of patients with acute MI. In patients with ischemic heart disease including patients after MI ACE inhibitors reduce mortality, risk of repeated MI as well as improve quality of life.

  16. High-intensity interval training has beneficial effects on cardiac remodeling through local renin-angiotensin system modulation in mice fed high-fat or high-fructose diets.

    Science.gov (United States)

    de Oliveira Sá, Guilherme; Dos Santos Neves, Vívian; de Oliveira Fraga, Shyrlei R; Souza-Mello, Vanessa; Barbosa-da-Silva, Sandra

    2017-11-15

    HIIT (high-intensity interval training) has the potential to reduce cardiometabolic risk factors, but the effects on cardiac remodeling and local RAS (renin-angiotensin system) in mice fed high-fat or high-fructose diets still need to be fully addressed. Sixty male C57BL/6 mice (12weeks old) were randomly divided into three groups, control (C), High-fat (HF), or High-fructose diet (HRU) and were monitored for eight weeks before being submitted to the HIIT. Each group was randomly assigned to 2 subgroups, one subgroup was started on a 12-week HIIT protocol (T=trained group), while the other subgroup remained non-exercised (NT=not-trained group). HIIT reduced BM and systolic blood pressure in high-fat groups, while enhanced insulin sensitivity after high-fat or high-fructose intake. Moreover, HIIT reduced left ventricular hypertrophy in HF-T and HFRU-T. Notably, HIIT modulated key factors in the local left ventricular renin-angiotensin-system (RAS): reduced protein expression of renin, ACE (Angiotensin-converting enzyme), and (Angiotensin type 2 receptor) AT2R in HF-T and HFRU-T groups but reduced (Angiotensin type 1 receptor) AT1R protein expression only in the high-fat trained group. HIIT modulated ACE2/Ang (1-7)/Mas receptor axis. ACE2 mRNA gene expression was enhanced in HF-T and HFRU-T groups, complying with elevated Mas (Mas proto-oncogene, G protein-coupled receptor) receptor mRNA gene expression after HIIT. This study shows the effectiveness of HIIT sessions in producing improvements in insulin sensitivity and mitigating LV hypertrophy, though hypertension was controlled only in the high-fat-fed submitted to HIIT protocol. Local RAS system in the heart mediates these findings and receptor MAS seems to play a pivotal role when it comes to the amelioration of cardiac structural and functional remodeling due to HIIT. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Cardiovascular actions of angiotensin-(1-7

    Directory of Open Access Journals (Sweden)

    Ferreira A.J.

    2005-01-01

    Full Text Available Angiotensin-(1-7 (Ang-(1-7 is now considered to be a biologically active member of the renin-angiotensin system. The functions of Ang-(1-7 are often opposite to those attributed to the main effector component of the renin-angiotensin system, Ang II. Chronic administration of angiotensin-converting enzyme inhibitors (ACEI increases 10- to 25-fold the plasma levels of this peptide, suggesting that part of the beneficial effects of ACEI could be mediated by Ang-(1-7. Ang-(1-7 can be formed from Ang II or directly from Ang I. Other enzymatic pathways for Ang-(1-7 generation have been recently described involving the novel ACE homologue ACE2. This enzyme can form Ang-(1-7 from Ang II or less efficiently by the hydrolysis of Ang I to Ang-(1-9 with subsequent Ang-(1-7 formation. The biological relevance of Ang-(1-7 has been recently reinforced by the identification of its receptor, the G-protein-coupled receptor Mas. Heart and blood vessels are important targets for the formation and actions of Ang-(1-7. In this review we will discuss recent findings concerning the biological role of Ang-(1-7 in the heart and blood vessels, taking into account aspects related to its formation and effects on these tissues. In addition, we will discuss the potential of Ang-(1-7 and its receptor as a target for the development of new cardiovascular drugs.

  18. Addition of ETA receptor blockade increases renoprotection provided by renin-angiotensin system blockade in 5/6 nephrectomized Ren-2 transgenic rats

    Czech Academy of Sciences Publication Activity Database

    Čertíková; Chábová, V.; Vernerová, Z.; Kujal, P.; Husková, Z.; Škaroupková, P.; Tesař, V.; Kramer, H. J.; Kompanowska; Jezierska, E.; Walkowska, A.; Sadowski, J.; Červenka, L.; Vaněčková, Ivana

    2014-01-01

    Roč. 118, č. 2 (2014), s. 297-305 ISSN 0024-3205 R&D Projects: GA ČR(CZ) GAP304/12/0259 Institutional support: RVO:67985823 Keywords : renal failure * 5/6 nephrectomy * renin-angiotensin * endothelin * survival Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 2.702, year: 2014

  19. Angiotensin II Type 1 receptor (AT1) signaling in astrocytes regulates synaptic degeneration-induced leukocyte entry to the central nervous system

    DEFF Research Database (Denmark)

    Füchtbauer, L; Groth-Rasmussen, Maria; Holm, Thomas Hellesøe

    2011-01-01

    in the dentate gyrus following axonal transection was totally abrogated in GFAP-IκBα-dn mice. Whereas angiotensin II was upregulated in microglia and astrocytes in the dentate gyrus post-lesion, AT1 was exclusively expressed on astrocytes. Blocking AT1 with Candesartan led to significant increase in numbers...

  20. Treatment of chronic heart failure with aldosterone-blocking agents

    NARCIS (Netherlands)

    van Veldhuisen, Dirk J.; Swedberg, Karl

    Three large randomized trials in advanced heart failure (RALES), in heart failure after myocardial infarction (EPHESUS), and most recently mild heart failure (EMPHASIS-HF) have firmly established the place of aldosterone-blocking agents in patients with heart failure. In this paper we will shortly

  1. Angiotensin-Converting Enzyme 2 Metabolizes and Partially Inactivates Pyr-Apelin-13 and Apelin-17: Physiological Effects in the Cardiovascular System.

    Science.gov (United States)

    Wang, Wang; McKinnie, Shaun M K; Farhan, Maikel; Paul, Manish; McDonald, Tyler; McLean, Brent; Llorens-Cortes, Catherine; Hazra, Saugata; Murray, Allan G; Vederas, John C; Oudit, Gavin Y

    2016-08-01

    Apelin peptides mediate beneficial effects on the cardiovascular system and are being targeted as potential new drugs. However, apelin peptides have extremely short biological half-lives, and improved understanding of apelin peptide metabolism may lead to the discovery of biologically stable analogues with therapeutic potential. We examined the ability of angiotensin-converting enzyme 2 (ACE2) to cleave and inactivate pyr-apelin 13 and apelin 17, the dominant apelin peptides. Computer-assisted modeling shows a conserved binding of pyr-apelin 13 and apelin 17 to the ACE2 catalytic site. In ACE2 knockout mice, hypotensive action of pyr-apelin 13 and apelin 17 was potentiated, with a corresponding greater elevation in plasma apelin levels. Similarly, pharmacological inhibition of ACE2 potentiated the vasodepressor action of apelin peptides. Biochemical analysis confirmed that recombinant human ACE2 can cleave pyr-apelin 13 and apelin 17 efficiently, and apelin peptides are degraded slower in ACE2-deficient plasma. The biological relevance of ACE2-mediated proteolytic processing of apelin peptides was further supported by the reduced potency of pyr-apelin 12 and apelin 16 on the activation of signaling pathways and nitric oxide production from endothelial cells. Importantly, although pyr-apelin 13 and apelin 17 rescued contractile function in a myocardial ischemia-reperfusion model, ACE2 cleavage products, pyr-apelin 12 and 16, were devoid of these cardioprotective effects. We designed and synthesized active apelin analogues that were resistant to ACE2-mediated degradation, thereby confirming that stable apelin analogues can be designed as potential drugs. We conclude that ACE2 represents a major negative regulator of apelin action in the vasculature and heart. © 2016 American Heart Association, Inc.

  2. Urinary alpha-1 antitrypsin and CD59 glycoprotein predict albuminuria development in hypertensive patients under chronic renin-angiotensin system suppression.

    Science.gov (United States)

    Gonzalez-Calero, Laura; Martin-Lorenzo, Marta; de la Cuesta, Fernando; Maroto, Aroa S; Baldan-Martin, Montserrat; Ruiz-Hurtado, Gema; Pulido-Olmo, Helena; Segura, Julian; Barderas, Maria G; Ruilope, Luis M; Vivanco, Fernando; Alvarez-Llamas, Gloria

    2016-01-16

    Hypertension is a multi-factorial disease of increasing prevalence and a major risk factor for cardiovascular mortality even in the presence of adequate treatment. Progression of cardiovascular disease (CVD) occurs frequently during chronic renin-angiotensin-system (RAS) suppression, and albuminuria is a marker of CV risk. High prevalence of albuminuria in treated hypertensive patients has been demonstrated, but there are no available markers able to predict evolution. The aim of this study was the identification of novel indicators of albuminuria progression measurable in urine of diabetic and non-diabetic patients. 1143 hypertensive patients under chronic treatment were followed for a minimum period of 3 years. Among them, 105 diabetic and non-diabetic patients were selected and classified in three groups according to albuminuria development during follow-up: (a) patients with persistent normoalbuminuria; (b) patients developing de novo albuminuria; (c) patients with maintained albuminuria. Differential urine analysis was performed by 2D gel electrophoresis (2D-DIGE) and further confirmed by liquid chromatography-mass spectrometry. Non-parametric statistical tests were applied. CD59 glycoprotein and alpha-1 antitrypsin (AAT) resulted already altered in patients developing albuminuria de novo, with a similar response in those with maintained albuminuria. A prospective study in a sub-group of normoalbuminuric patients who were clinically followed up for at least 1 year from urine sampling, revealed CD59 and AAT proteins significantly varied in the urine collected from normoalbuminurics who will negatively progress, serving as predictors of future albuminuria development. CD59 and AAT proteins are significantly altered in hypertensive patients developing albuminuria. Interestingly, CD59 and AAT are able to predict, in normoalbuminuric individuals, who will develop albuminuria in the future, being potential predictors of vascular damage and CV risk. These findings

  3. Clinical impacts of inhibition of renin-angiotensin system in patients with acute ST-segment elevation myocardial infarction who underwent successful late percutaneous coronary intervention.

    Science.gov (United States)

    Park, Hyukjin; Kim, Hyun Kuk; Jeong, Myung Ho; Cho, Jae Yeong; Lee, Ki Hong; Sim, Doo Sun; Yoon, Nam Sik; Yoon, Hyun Ju; Hong, Young Joon; Kim, Kye Hun; Park, Hyung Wook; Kim, Ju Han; Ahn, Youngkeun; Cho, Jeong Gwan; Park, Jong Chun; Kim, Young Jo; Cho, Myeong Chan; Kim, Chong Jim

    2017-01-01

    Successful percutaneous coronary intervention (PCI) of the occluded infarct-related artery (IRA) in latecomers may improve long-term survival mainly by reducing left ventricular remodeling. It is not clear whether inhibition of renin-angiotensin system (RAS) brings additional better clinical outcomes in this specific population subset. Between January 2008 and June 2013, 669 latecomer patients with acute ST-segment elevation myocardial infarction (STEMI) (66.2±12.1 years, 71.0% males) in Korea Acute Myocardial Infarction Registry (KAMIR) who underwent a successful PCI were enrolled. The study population underwent a successful PCI for a totally occluded IRA. They were divided into two groups according to whether they were prescribed RAS inhibitors at the time of discharge: group I (RAS inhibition, n=556), and group II (no RAS inhibition, n=113). During the one-year follow-up, major adverse cardiac events (MACE), which consist of cardiac death and myocardial infarction, occurred in 71 patients (10.6%). There were significantly reduced incidences of MACE in the group I (hazard ratio=0.34, 95% confidence interval 0.199-0.588, p=0.001). In subgroup analyses, RAS inhibition was beneficial in patients with male gender, history of hypertension or diabetes mellitus, and even in patients with left ventricular ejection fraction (LVEF) ≥40%. In the baseline and follow-up echocardiographic data, benefit in changes of LVEF and left ventricular end-systolic volume was noted in group I. In latecomers with STEMI, RAS inhibition improved long-term clinical outcomes after a successful PCI, even in patients with low risk who had relatively preserved LVEF. Copyright © 2016 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  4. Angiotensin II type 1 receptor (A1166C) gene polymorphism in ...

    African Journals Online (AJOL)

    Abstract. Background: Genetic variability in the genes of different components of renin-angiotensin system (RAS) is likely to contribute for its heterogenous association in renal diseased patients. Among the candidate genes of RAS, angiotensin II type 1 receptor gene polymorphism (AT1R A1166C) seems to be particularly ...

  5. Angiotensin II type 1 receptor blockade partially attenuates hypoxia-induced pulmonary hypertension in newborn piglets: relationship with the nitrergic system

    Energy Technology Data Exchange (ETDEWEB)

    Camelo, J.S. Jr. [Departamento de Puericultura e Pediatria, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Martins, A.R. [Departamento de Farmacologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Instituto de Ciências Biológicas, Universidade Federal do Triângulo Mineiro, Uberaba, MG (Brazil); Rosa, E. [Departamento de Farmacologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Ramos, S.G. [Departamento de Patologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SPBrasil (Brazil); Hehre, D.; Bancalari, E.; Suguihara, C. [Department of Pediatrics, Division of Neonatology, Neonatal Developmental Biology Laboratory, University of Miami Miller School of Medicine, Miami, FL (United States)

    2012-02-10

    The objective of this study was to observe possible interactions between the renin-angiotensin and nitrergic systems in chronic hypoxia-induced pulmonary hypertension in newborn piglets. Thirteen chronically instrumented newborn piglets (6.3 ± 0.9 days; 2369 ± 491 g) were randomly assigned to receive saline (placebo, P) or the AT{sub 1} receptor (AT{sub 1}-R) blocker L-158,809 (L) during 6 days of hypoxia (FiO{sub 2} = 0.12). During hypoxia, pulmonary arterial pressure (Ppa; P < 0.0001), pulmonary vascular resistance (PVR; P < 0.02) and the pulmonary to systemic vascular resistance ratio (PVR/SVR; P < 0.05) were significantly attenuated in the L (N = 7) group compared to the P group (N = 6). Western blot analysis of lung proteins showed a significant decrease of endothelial NOS (eNOS) in both P and L animals, and of AT{sub 1}-R in P animals during hypoxia compared to normoxic animals (C group, N = 5; P < 0.01 for all groups). AT{sub 1}-R tended to decrease in L animals. Inducible NOS (iNOS) did not differ among P, L, and C animals and iNOS immunohistochemical staining in macrophages was significantly more intense in L than in P animals (P < 0.01). The vascular endothelium showed moderate or strong eNOS and AT{sub 1}-R staining. Macrophages and pneumocytes showed moderate or strong iNOS and AT{sub 1}-R staining, but C animals showed weak iNOS and AT{sub 1}-R staining. Macrophages of L and P animals showed moderate and weak AT{sub 2}-R staining, respectively, but the endothelium of all groups only showed weak staining. In conclusion, pulmonary hypertension induced by chronic hypoxia in newborn piglets is partially attenuated by AT{sub 1}-R blockade. We suggest that AT{sub 1}-R blockade might act through AT{sub 2}-R and/or Mas receptors and the nitrergic system in the lungs of hypoxemic newborn piglets.

  6. Reducing Disease Activity in Animal Models of MS by Activation of the Protective Arm of the Renin-Angiotensin System

    Science.gov (United States)

    2015-10-01

    in EAE is to skew expression of the RAS system in the brain to the anti- inflammatory, regulatory arm. In our proposal we hypothesized that if we were...followed by progressive accruing disability and paralysis with stabilization at a high level of disability. MOG-EAE is similar in many aspects to...progressive MS with extensive neuronal damage both in the brain and spinal cord, and once established treatment intervention can be very limited. Spinal

  7. Angioedema related to Angiotensin inhibitors.

    Science.gov (United States)

    Knecht, Stephanie E; Dunn, Steven P; Macaulay, Tracy E

    2014-10-01

    Angiotensin inhibitors have been extensively evaluated in clinical trials and have demonstrated significant reductions in morbidity and mortality following myocardial infarction and stroke, as well as in patients with heart failure or who are at risk of cardiovascular disease. Further, both angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are frequently prescribed for the treatment of hypertension and to preserve renal function in patients with diabetes mellitus and chronic kidney disease. Angioedema is a known, but rare, adverse effect of ACEIs and ARBs. Therefore, it is important for clinicians to have a thorough understanding of risks and benefits of prescribing these medications, particularly in patients with a history of angioedema. This review describes the literature evaluating the incidence and cross-reactivity of angioedema with ACEIs and ARBs in order to provide guidance for clinical decision making. © The Author(s) 2014.

  8. Renoprotective effects of angiotensin II receptor blockade in type 1 diabetic patients with diabetic nephropathy

    DEFF Research Database (Denmark)

    Andersen, S; Tarnow, L; Rossing, P

    2000-01-01

    BACKGROUND: Angiotensin I-converting enzyme (ACE) inhibitors reduce angiotensin II formation and induce bradykinin accumulation. Animal studies suggest that bradykinin may play a role for the effects of ACE inhibition on blood pressure and kidney function. Therefore, we compared the renal and hem...... inhibition is primarily caused by interference in the renin-angiotensin system. Our study suggest that losartan represents a valuable new drug in the treatment of hypertension and proteinuria in type 1 diabetic patients with diabetic nephropathy....... and hemodynamic effects of specific intervention in the renin-angiotensin system by blockade of the angiotensin II subtype-1 receptor to the effect of ACE inhibition. METHODS: A randomized, double-blind, cross-over trial was performed in 16 type 1 diabetic patients (10 men), age 42 +/- 2 years (mean +/- SEM...

  9. Distribution of Human Leukocyte Antigen alleles in Systemic Lupus Erythematosus patients with Angiotensin Converting Enzyme Insertion/Deletion Polymorphism

    Directory of Open Access Journals (Sweden)

    Nageen Hussain

    2013-02-01

    Full Text Available Systemic Lupus Erythematosus is one of the classic examples of autoimmune diseases among human beings and is a rare disease in Pakistani population. Clinically it is a quite diverse and complicated autoimmune disease in a sense that it involves multiple organs of the body and mimics with other diseases as well. This study focused on the distribution of HLA alleles in SLE patients with ACE I/D Polymorphism. A total of 122 individuals were enrolled in this study, 61 were the SLE patients who fulfilled revised ACR criteria and 61 were the healthy controls. Mean age of SLE patients at diagnosis was 30.35 ± 1.687 years (12-68 years. ACE gene I/D polymorphism was performed by nested PCR and DNA based HLA typing technique was used. ACE gene I/D polymorphism of Intron16 was studied and found to be involved in the activity of SLE. There is high frequency of HLA-A*01, HLA-B*40, HLA-DRB1*01 alleles in SLE patients with ACE DD genotype. The distribution of HLA-A, -B, -DRB1 alleles was analyzed in SLE patients with various disease phenotypes. HLA-A*01 and HLA-B*40 was the most common allele found in SLE patients with the involvement of skin. HLA-A*01, -A*03, HLA-B*13 and -B*46 were common in SLE patients with arthritis while HLA-A*26 and -A*69 were commonly found in Lupus nephritis cases. SLE patients involving both skin and kidney had an allele HLA-DRB1*01 common in them.

  10. Antiproteinuric effect of add-on paricalcitol in CKD patients under maximal tolerated inhibition of renin-angiotensin system: a prospective observational study

    Directory of Open Access Journals (Sweden)

    De Nicola Luca

    2012-11-01

    Full Text Available Abstract Background Whether paricalcitol (PCT reduces proteinuria in the presence of intensified inhibition of Renin-Angiotensin-System (RAS is poorly studied. We evaluated the antiproteinuric effect of PCT in non-dialysis chronic kidney disease (CKD patients with proteinuria greater than 0.5 g/24 h persisting despite anti-RAS therapy titrated to minimize proteinuria in the absence of adverse effects. Methods Forty-eight CKD patients were studied in the first six months of add-on oral PCT (1 mcg/day and three months after drug withdrawal. Results Males were 87.5%, age 63 ± 14 yrs, systolic/diastolic blood pressure (BP 143 ± 22/78 ± 11 mmHg, eGFR 29.7 ± 14.5 mL/min/1.73 m2, diabetes 40%, and cardiovascular disease 38%. At referral in the center (28 months prior to study baseline, proteinuria was 2.44 (95% CI 1.80-3.04 g/24 h with 6 patients not receiving any anti-RAS and 42 treated with a single agent, at low dosage in most cases. At study baseline, twenty patients were under 2–3 anti-RAS drugs while twenty-eight received 1 agent at full dose and proteinuria resulted to be reduced versus referral to 1.23 g/24 h (95%CI 1.00-1.51. Six months of add-on PCT significantly decreased proteinuria to 0.61 g/24 h (95%CI 0.40-0.93, with levels less than 0.5 g/24 h achieved in 37.5% patients, in the absence of changes of BP and GFR. Proteinuria recovered to basal value after drug withdrawal. The extent of antiproteinuric response to PCT was positively associated with diabetes, eGFR and daily Na excretion (R2 = 0.459, P  Conclusions In CKD patients, add-on PCT induces a significant reduction of proteinuria that is evident despite intensified anti-RAS therapy and larger in the presence of diabetes, higher GFR and unrestricted salt intake.

  11. Antiproteinuric effect of add-on paricalcitol in CKD patients under maximal tolerated inhibition of renin-angiotensin system: a prospective observational study.

    Science.gov (United States)

    De Nicola, Luca; Conte, Giuseppe; Russo, Domenico; Gorini, Antonio; Minutolo, Roberto

    2012-11-20

    Whether paricalcitol (PCT) reduces proteinuria in the presence of intensified inhibition of Renin-Angiotensin-System (RAS) is poorly studied. We evaluated the antiproteinuric effect of PCT in non-dialysis chronic kidney disease (CKD) patients with proteinuria greater than 0.5 g/24 h persisting despite anti-RAS therapy titrated to minimize proteinuria in the absence of adverse effects. Forty-eight CKD patients were studied in the first six months of add-on oral PCT (1 mcg/day) and three months after drug withdrawal. Males were 87.5%, age 63 ± 14 yrs, systolic/diastolic blood pressure (BP) 143 ± 22/78 ± 11 mmHg, eGFR 29.7 ± 14.5 mL/min/1.73 m(2), diabetes 40%, and cardiovascular disease 38%. At referral in the center (28 months prior to study baseline), proteinuria was 2.44 (95% CI 1.80-3.04) g/24 h with 6 patients not receiving any anti-RAS and 42 treated with a single agent, at low dosage in most cases. At study baseline, twenty patients were under 2-3 anti-RAS drugs while twenty-eight received 1 agent at full dose and proteinuria resulted to be reduced versus referral to 1.23 g/24 h (95%CI 1.00-1.51). Six months of add-on PCT significantly decreased proteinuria to 0.61 g/24 h (95%CI 0.40-0.93), with levels less than 0.5 g/24 h achieved in 37.5% patients, in the absence of changes of BP and GFR. Proteinuria recovered to basal value after drug withdrawal. The extent of antiproteinuric response to PCT was positively associated with diabetes, eGFR and daily Na excretion (R(2) = 0.459, P proteinuria that is evident despite intensified anti-RAS therapy and larger in the presence of diabetes, higher GFR and unrestricted salt intake.

  12. ASSOCIATION OF GENE POLYMORPHISMS OF THE RENIN-ANGIOTENSIN SYSTEM AND ENDOTHELIAL DYSFUNCTION WITH DEVELOPMENT AND SEVERITY OF PORTAL HYPERTENSION IN PATIENTS WITH CHRONIC HEPATITIS C

    Directory of Open Access Journals (Sweden)

    O. V. Taratina

    2016-01-01

    Full Text Available Background: At present, much attention is paid to genetic factors explaining the clinical course of chronic hepatitis C. Aim: To evaluate an association of the gene polymorphisms involved in the formation of endothelial dysfunction (NOS3 894G/T, CYBA 242C/T, MTHFR 677C/T and encoding components of the renin-angiotensin system (ATR1 1166A/C, AGT (-6G/T and 235M/T with development and severity of portal hypertension syndrome in patients with chronic hepatitis C. Materials and methods: 162 patients with chronic hepatitis C and HCV-related cirrhosis (114 women and 48 men were divided into the following groups: no portal hypertension (n = 98, "compensated" (n = 19 and "decompensated" (n = 45 portal hypertension. The gene polymorphisms were assessed by molecular genetic methods. Results: TT genotype of CYBA was more common in patients with portal hypertension than in those without (odds ratio (OR for TT = 3.59, p = 0.031. This difference becomes larger when comparing the decompensated portal hypertension group with the no portal hypertension group (OR TT = 5.46, p = 0.009. Other gene polymorphisms were not associated with development or decompensation of portal hypertension. Multivariate analysis of the impact of genetic, clinical and demographic factors showed that portal hypertension was associated primarily with patients age at the time of the study (Wald's х2 = 14.99 and with their body mass index (Wald's х2 = 4.35. After exclusion of these population-wide risk factors from the model, the development of portal hypertension correlated with the carriage of 235TT genotype of CYBA (Wald's х2 = 6.07, OR = 4.29 and (-6AA genotype AGT (Wald's х2 = 4.73, OR = 4.13, as well as with the lack of protective 235TT genotype AGT (Wald's х2 = 4.06, OR = 0.33. The combined effects of the studied gene polymorphisms on decompensation of the portal hypertension in patients with chronic HCV infection were similar. Conclusion: The development and increase in

  13. Adrenal vein sampling in 22 patients with primary aldosteronism

    International Nuclear Information System (INIS)

    Kanamoto, Takaaki; Ueda, Hiroyuki; Hiraoka, Taizo; Ito, Hirofumi; Hayakawa, Katsumi; Chusho, Hideki; Yoshimasa, Takaaki; Tanikake, Masato

    2007-01-01

    We evaluated 22 patients who had been diagnosed with primary aldosteronism (PA) and undergone adrenal venous sampling (AVS) in our hospital. Blood sampling was technically successful in all patients and, in terms of results, endocrinologically successful in 20 and unsuccessful in 2. We achieved a success rate of over 90% by preoperatively confirming the vascular anatomy by multi detector row CT (MDCT), selecting a catheter suitable for insertion into the right adrenal vein, and using an extension tube for children at the time of sampling. Of the 14 patients diagnosed with aldosterone producing adenoma (APA) by AVS, 7 underwent adrenal adenomectomy, and achieved improvement in blood pressure and biochemical test results. Thus, AVS is useful for the diagnosis and treatment planning of PA, and the demand for it will grow in the future. (author)

  14. Renal damage in primary aldosteronism: results of the PAPY Study.

    Science.gov (United States)

    Rossi, Gian Paolo; Bernini, Giampaolo; Desideri, Giovambattista; Fabris, Bruno; Ferri, Claudio; Giacchetti, Gilberta; Letizia, Claudio; Maccario, Mauro; Mannelli, Massimo; Matterello, Mee-Jung; Montemurro, Domenico; Palumbo, Gaetana; Rizzoni, Damiano; Rossi, Ermanno; Pessina, Achille Cesare; Mantero, Franco

    2006-08-01

    Primary aldosteronism (PA) has been associated with cardiovascular hypertrophy and fibrosis, in part independent of the blood pressure level, but deleterious effects on the kidneys are less clear. Likewise, it remains unknown if the kidney can be diversely involved in PA caused by aldosterone-producing adenoma (APA) and idiopathic hyperaldosteronism (IHA). Hence, in the Primary Aldosteronism Prevalence in Italy (PAPY) Study, a prospective survey of newly diagnosed consecutive patients referred to hypertension centers nationwide, we sought signs of renal damage in patients with PA and in comparable patients with primary hypertension (PH). Patients (n = 1180) underwent a predefined screening protocol followed by tests for confirming PA and identifying the underlying adrenocortical pathology. Renal damage was assessed by 24-hour urine albumin excretion (UAE) rate and glomerular filtration rate (GFR). UAE rate was measured in 490 patients; all had a normal GFR. Of them, 31 (6.4%) had APA, 33 (6.7%) had IHA, and the rest (86.9%) had PH. UAE rate was predicted (P body mass index, age, urinary Na+ excretion, serum K+, and mean blood pressure. Covariate-adjusted UAE rate was significantly higher in APA and IHA than in PH patients; there were more patients with microalbuminuria in the APA and IHA than in the PH group (P = 0.007). Among the hypertensive patients with a preserved GFR, those with APA or IHA have a higher UAE rate than comparable PH patients. Thus, hypertension because of excess autonomous aldosterone secretion features an early and more prominent renal damage than PH.

  15. Cardiovascular changes in patients with primary aldosteronism after surgical or medical treatment.

    Science.gov (United States)

    Bernini, G; Bacca, A; Carli, V; Carrara, D; Materazzi, G; Berti, P; Miccoli, P; Pisano, R; Tantardini, V; Bernini, M; Taddei, S

    2012-03-01

    Data on the cardiovascular middle-term follow-up of patients with primary aldosteronism (PA) are scanty. To detect the cardiovascular effects of surgery in patients with aldosterone (ALD)-producing adenoma (APA) and of pharmacotherapy in those with bilateral adrenal hyperplasia (BAH), a prospective study involving 60 consecutive patients with PA was performed. MATERIAL/ METHODS: Clinical, biochemical, and cardiovascular assessment was obtained before and after (31.5±4.4 months) surgery or proper medical treatment (32.1±5.0 months) in 19 and 41 patients, respectively. As expected, plasma ALD normalized in all operated patients, while in the other group it did not change. Systolic and diastolic blood pressure decreased (pbody mass index (p<0.0008), drug number (p<0.03), and ALD/plasma renin activity ratio (p<0.01). Allocating the patients according to plasma ALD and cardiac parameters, patients who presented ALD reduction during the study also had a decrement in cardiac mass (p<0.04). Our data indicate that in patients with PA the removal of ALD excess by surgery in APA is effective in reducing blood pressure and in improving cardiac parameters, while anti-hypertensive therapy in BAH shows less positive impact on cardiovascular system. © 2012, Editrice Kurtis.

  16. Overview of the genetic determinants of primary aldosteronism

    Directory of Open Access Journals (Sweden)

    Al-Salameh A

    2014-04-01

    Full Text Available Abdallah Al-Salameh,1 Régis Cohen,2 Rachel Desailloud3 1Service de Diabétologie, Endocrinologie et Maladies Métaboliques, Centre Hospitalier de Creil, Creil, France; 2Service d'Endocrinologie, Centre Hospitalier de Saint-Denis, Saint-Denis, France; 3Service d'Endocrinologie, Diabétologie et Nutrition, Centre Hospitalier Universitaire d'Amiens, Amiens, France Abstract: Primary aldosteronism is the most common cause of secondary hypertension. The syndrome accounts for 10% of all cases of hypertension and is primarily caused by bilateral adrenal hyperplasia or aldosterone-producing adenoma. Over the last few years, the use of exome sequencing has significantly improved our understanding of this syndrome. Somatic mutations in the KCNJ5, ATP1A1, ATP2B3 or CACNA1D genes are present in more than half of all cases of aldosterone-producing adenoma (~40%, ~6%, ~1% and ~8%, respectively. Germline gain-of-function mutations in KCNJ5 are now known to cause familial hyperaldosteronism type III, and an additional form of genetic hyperaldosteronism has been reported in patients with germline mutations in CACNA1D. These genes code for channels that control ion homeostasis across the plasma membrane of zona glomerulosa cells. Moreover, all these mutations modulate the same pathway, in which elevated intracellular calcium levels lead to aldosterone hyperproduction and (in some cases adrenal cell proliferation. From a clinical standpoint, the discovery of these mutations has potential implications for patient management. The mutated channels could be targeted by drugs, in order to control hormonal and overgrowth-related manifestations. Furthermore, some of these mutations are associated with high cell turnover and may be amenable to diagnosis via the sequencing of cell-free (circulating DNA. However, genotype-phenotype correlations in patients harboring these mutations have yet to be characterized. Despite this recent progress, much remains to be done to

  17. Aldosterone-induced signalling and cation transport in the distal nephron.

    LENUS (Irish Health Repository)

    Thomas, Warren

    2008-10-01

    Aldosterone is an important regulator of Na(+) and K(+) transport in the distal nephron modulating the surface expression of transporters through the action of the mineralocorticoid receptor as a ligand-dependent transcription factor. Aldosterone stimulates the rapid activation of protein kinase-based signalling cascades that modulate the genomic effects of the hormone. Evidence is accumulating about the multi-factorial regulation of the epithelial sodium channel (ENaC) by aldosterone. Recent published data suggests that the activation of a novel PKC\\/PKD signalling pathway through the c-Src-dependent trans-activation of epidermal growth factor receptor contributes to early ENaC trafficking in response to aldosterone.

  18. LPO and antioxidant defense in the stomach of albino rats injected with angiotensin II and enalapril maleate.

    Science.gov (United States)

    Pikalova, V M; Postupaev, V V; Timoshin, S S

    2003-04-01

    The effects of components of angiotensin II system on LPO and antioxidant defense in the stomach of adult albino rats were studied using biochemical and chemiluminescent methods. Five intraperitoneal injections of angiotensin II in a dose of 100 micro/kg activated LPO and inhibited antioxidant processes in the studied tissues. Oral therapy with enalapril maleate (inhibitor of angiotensin-converting enzyme) in a daily dose of 10 mg/kg for 2 weeks normalized stress-activated LPO processes in gastric tissue.

  19. The influence of cardiac resynchronization therapy on selected inflammatory markers and aldosterone levels in patients with chronic heart failure.

    Science.gov (United States)

    Przybyła, Anna; Czarnecka, Danuta; Kusiak, Aleksander; Wiliński, Jerzy; Sondej, Tomasz; Jastrzebski, Marek; Kawecka-Jaszcz, Kalina

    2011-01-01

    The aim of the study was to assess the influence of cardiac resynchronization therapy(CRT) on a series of humoral parameters crucial for the pathophysiology of chronic heart failure such as aldosterone or the inflammatory markers. Thirty eight consecutive patients (aged 66.3 +/- 9.6 years, 31 men - 82% ) with chronic heart failure (57.9% with ischaemic background and 42.1% of non-ischaemic etiology) in stable for at least 3 months, NYHA class III - IV despite optimized pharmacotherapy, with left ventricular ejection fraction (LVEF) or = 120 ms) had the blood serum tested for the concentrations of interleukin-6 (IL-6), interleukin-18 (IL-18), C-reactive protein (CRP) and aldosterone before and 12-16 weeks after CRT introduction. In the study group aldosterone concentrations were significantly reduced. Among the inflammatory markers the level of IL-6 decreased, IL-18 concentrations showed a falling trend (445.1 +/- 225.7 pg/ml vs 418.4 +/- 229.6 pg/ml, p = 0.052), whereas no change of CRP serum contain was noted. It was showed that cardiac resynchronization therapy had an impact on systemic inflammation and hormonal status in patients with chronic heart failure during short-term observation.

  20. Long-term use of drugs affecting the renin-angiotensin system and the risk of cancer. A population-based case-control study

    DEFF Research Database (Denmark)

    Hallas, Jesper; Depont Christensen, Rene; Andersen, Morten

    2012-01-01

    Aims: A recent meta-analysis of clinical trials has demonstrated a small excess of cancers in persons that had been allocated to angiotensin-receptor blockers (ARBs). We undertook this observational study to look at dose-response and dose-duration effects and look for specificity with respect...... for each case by a risk-set sampling. Data on medication was retrieved from the Danish National Prescription Registry. We defined long-term exposure as at least 1000 defined daily doses redeemed within the past five years. Confounders were controlled by conditional logistic regression. Results: The odds...

  1. Influence of prenatal application of angiotensin II and postnatal salt diet on GABAergic and oxytocin system in rat brain steam and cerebellum

    International Nuclear Information System (INIS)

    Jackova, L.; Olexova, L.; Svitok, P.; Senko, T.; Stefanik, P.

    2015-01-01

    Our goal was to determinate how gene expression of GABA transporter 1 (GAT1), glutamate decarboxylase