eplerenone and candesartan

We investigated the effects of the aldosterone blocker eplerenone alone and in combination with angiotensin II type 1 receptor antagonist on ventricular remodeling in rats with left ventricular (LV) dysfunction after extensive myocardial infarction (MI). Adding an aldosterone antagonist to an ACE inhibitor reduces mortality and morbidity in heart failure. Starting 1 day after MI, rats were treated with placebo, eplerenone (100 mg/kg/day), the angiotensin type 1 receptor antagonist candesartan (1 mg/kg/day), or a combination of both for nine weeks. Both monotherapies attenuated the rise in LV end-diastolic dimension (LVDd) and LV end-diastolic volume (LVEDV) compared with placebo, whereas combined treatment further attenuated LVDd and LVEDV and significantly improved LV function. Increased collagen type I and III gene expressions in the noninfarcted LV myocardium from MI placebo rats was attenuated by candesartan, but almost completely prevented by eplerenone and eplerenone/candesartan. The addition of eplerenone to candesartan prevented the increases in LV gene expression of ANP and BNP more effectively than either monotherapy. The aldosterone blocker eplerenone improved LV remodeling in rats with LV dysfunction after extensive MI. Combination therapy with an candesartan substantially potentiates this effect by a complementary prevention of LV fibrosis, cardiac hypertrophy, and molecular alterations.

Topics: Angiotensin Receptor Antagonists; Animals; Benzimidazoles; Biphenyl Compounds; Eplerenone; Mineralocorticoid Receptor Antagonists; Myocardial Infarction; Rats; Spironolactone; Tetrazoles; Ventricular Dysfunction, Left; Ventricular Remodeling

Obesity increases the risk of proteinuria and chronic renal insufficiency and hastens the progression of renal diseases. Increased activity of renin-angiotensin-aldosterone system and elevated levels of aldosterone are common in obese patients. No studies have compared the efficacy of the currently available antiproteinuric strategies (ACE inhibitors -ACEI-, angiotensin receptor blockers -ARB-, aldosterone antagonists) in obese patients with proteinuric renal diseases.. Single centre, prospective, randomized study. Twelve obese patients (body mass index > 30 Kg/m2) with proteinuria > 0.5 g/24 h were selected from our outpatient renal clinic. Patients were consecutively treated during 6 weeks with an ACEI (lisinopril 20 mg/day), combined therapy ACEI+ARB (lisinopril 10 mg/day + candesartan 16 mg/day) and eplerenone (25 mg/day) in random order. A drug washout period of 6 weeks was established between the different treatment periods. The primary outcome point was the change in 24-h proteinuria at the end of each treatment period and the number of patients showing a proteinuria reduction greater than 25% of baseline.. The reduction in proteinuria induced by lisinopril (11.3+/-34.8%) was not statistically significant with respect to baseline, whereas that of lisinopril plus candesartan (26.9+/-30.6%) and eplerenone (28.4+/-31.6%) showed a statistically significant difference both with respect to baseline values and to lisinopril group. The number of patients who showed a greater than 25% proteinuria reduction was significantly higher with eplerenone (67%) and lisinopril+candesartan (67%) than with lisinopril (25%).. Monotherapy with an aldosterone antagonist and combination therapy with ACEI+ARB were more effective than ACEI monotherapy to reduce proteinuria in obese patients with proteinuric renal diseases.

Topics: Adult; Aged; Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Benzimidazoles; Biphenyl Compounds; Eplerenone; Female; Humans; Lisinopril; Male; Middle Aged; Mineralocorticoid Receptor Antagonists; Obesity; Prospective Studies; Proteinuria; Spironolactone; Tetrazoles

The efficacy and tolerability of eplerenone, a selective aldosterone blocker, was assessed when added to existing antihypertensive therapy with an ACE inhibitor or an angiotensin II receptor blocker (ARB). Hypertensive patients (n=341) whose blood pressure (BP) was not controlled despite ACE inhibitor or ARB were randomized (double-blind) to receive 50 mg eplerenone (increasing to 100 mg if required) once daily or placebo for 8 weeks. Diastolic and systolic BP and adverse events were recorded. By study end (week 8), mean seated diastolic BP was significantly reduced from week 0 among patients receiving eplerenone/ARB (-12.7+/-0.81 mm Hg) compared with those receiving placebo/ARB (-9.3+/-0.83 mm Hg). The change in mean seated diastolic BP was -9.9+/-0.88 mm Hg in eplerenone/ACE inhibitor patients and -8.0+/-0.86 mm Hg in placebo/ACE inhibitor patients (P=NS). Systolic BP levels were also significantly lower at week 8 for eplerenone/ACE inhibitor (-13.4+/-1.35 mm Hg) and eplerenone/ARB (-16.0+/-1.37 mm Hg) patients, respectively, compared with placebo/ACE inhibitor (-7.5+/-1.31 mm Hg) and placebo/ARB patients (-9.2+/-1.41 mm Hg). Adverse events were generally nonsevere and not significantly different between eplerenone and placebo. This study demonstrated that in patients whose BP was not controlled with an ACE inhibitor or ARB, the addition of eplerenone over an 8-week period significantly lowered systolic BP in both groups and diastolic BP in ARB patients. Selective aldosterone blockade with eplerenone, therefore, may be useful add-on therapy in hypertensive patients inadequately controlled on ACE inhibitor or ARB alone.

Topics: Abdominal Pain; Adolescent; Adult; Aged; Aged, 80 and over; Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Antihypertensive Agents; Benzimidazoles; Benzoates; Biphenyl Compounds; Blood Pressure; Diarrhea; Double-Blind Method; Drug Therapy, Combination; Eplerenone; Female; Headache; Heart Rate; Humans; Hypertension; Irbesartan; Losartan; Male; Middle Aged; Patient Dropouts; Renin-Angiotensin System; Spironolactone; Telmisartan; Tetrazoles; Treatment Outcome; Valine; Valsartan

A 28-year-old man was referred to our hospital for the treatment of congestive heart failure and severe hypertension. The patient was diagnosed with malignant phase hypertension based on the presence of marked hypertension with left ventricular hypertrophy, exudate retinopathy, and renal failure. Intensive therapy for hypertension and heart failure with a combination of antihypertensive drugs including nitroglycerin, nifedipine, eplerenone and candesartan successfully lowered his blood pressure and further improved the renal function. Eplerenone could be one of the choices of antihypertensive drugs in combination therapy in patients with malignant phase hypertension with progressive heart and renal failure.

Topics: Adrenergic beta-Antagonists; Adult; Antihypertensive Agents; Benzimidazoles; Biphenyl Compounds; Calcium Channel Blockers; Creatinine; Drug Therapy, Combination; Eplerenone; Heart Failure; Humans; Hypertension, Malignant; Male; Nifedipine; Nitroglycerin; Obesity; Renal Insufficiency; Spironolactone; Tetrazoles; Treatment Outcome; Vasodilator Agents

Recently, we could show that angiotensin II, the reactive peptide of the blood pressure-regulating renin-angiotensin-aldosterone-system, causes the formation of reactive oxygen species and DNA damage in kidneys and hearts of hypertensive mice. To further investigate on the one hand the mechanism of DNA damage caused by angiotensin II, and on the other hand possible intervention strategies against end-organ damage, the effects of substances interfering with the renin-angiotensin-aldosterone-system on angiotensin II-induced genomic damage were studied.. In C57BL/6-mice, hypertension was induced by infusion of 600 ng/kg • min angiotensin II. The animals were additionally treated with the angiotensin II type 1 receptor blocker candesartan, the mineralocorticoid receptor blocker eplerenone and the antioxidant tempol. DNA damage and the activation of transcription factors were studied by immunohistochemistry and protein expression analysis.. Administration of angiotensin II led to a significant increase of blood pressure, decreased only by candesartan. In kidneys and hearts of angiotensin II-treated animals, significant oxidative stress could be detected (1.5-fold over control). The redox-sensitive transcription factors Nrf2 and NF-κB were activated in the kidney by angiotensin II-treatment (4- and 3-fold over control, respectively) and reduced by all interventions. In kidneys and hearts an increase of DNA damage (3- and 2-fold over control, respectively) and of DNA repair (3-fold over control) was found. These effects were ameliorated by all interventions in both organs. Consistently, candesartan and tempol were more effective than eplerenone.. Angiotensin II-induced DNA damage is caused by angiotensin II type 1 receptor-mediated formation of oxidative stress in vivo. The angiotensin II-mediated physiological increase of aldosterone adds to the DNA-damaging effects. Blocking angiotensin II and mineralocorticoid receptors therefore has beneficial effects on end-organ damage independent of blood pressure normalization.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldosterone; Angiotensin II; Angiotensin II Type 1 Receptor Blockers; Animals; Antioxidants; Benzimidazoles; Biphenyl Compounds; Blood Pressure; Cyclic N-Oxides; Deoxyguanosine; DNA Damage; DNA Repair; Enzyme Activation; Eplerenone; Guanosine; Heart; Hypertension; Kidney; Male; Mice; Mice, Inbred C57BL; Mineralocorticoid Receptor Antagonists; NF-E2-Related Factor 2; NF-kappa B; Oxidative Stress; Reactive Oxygen Species; Renin-Angiotensin System; Spin Labels; Spironolactone; Tetrazoles

A chronic increase in circulating angiotensin II (Ang II) activates an aldosterone-mineralocorticoid receptor-ouabain neuromodulatory pathway in the brain that increases neuronal activation in hypothalamic nuclei, such as the paraventricular nucleus (PVN) and causes progressive hypertension. Several models of chronic sympathetic hyperactivity are associated with an increase in AT1 and glutamate receptor activation in the PVN. The current study evaluated whether increased angiotensin type 1 (AT1) and glutamate receptor-dependent signaling in the PVN contributes to the maintenance of blood pressure (BP) in Ang II-hypertensive Wistar rats, and the role of aldosterone-mineralocorticoid receptor pathway in this enhanced signaling. After subcutaneous infusion of Ang II for 2 weeks, in conscious rats BP and heart rate were recorded after (1) 10-minute bilateral infusions of candesartan and kynurenate in the PVN; (2) 1 hour intracerebroventricular infusion of eplerenone, and (3) candesartan and kynurenate after eplerenone. Candesartan or kynurenate in the PVN fully reversed the increase in BP from circulating Ang II. Kynurenate after candesartan or candesartan after kynurenate did not further lower BP. Intracerebroventricular infusion of eplerenone at 16 hours after its infusion fully reversed the increase in BP from circulating Ang II. After eplerenone, candesartan and kynurenate in the PVN did not further decrease BP. These findings suggest that increased mineralocorticoid receptor activation in the brain activates a slow neuromodulatory pathway that maintains enhanced AT1 and glutamate receptor-dependent signaling in the PVN, and thereby the hypertension from a chronic increase in circulating Ang II.

Topics: Angiotensin II; Angiotensin II Type 1 Receptor Blockers; Animals; Benzimidazoles; Biphenyl Compounds; Blood Pressure; Disease Models, Animal; Eplerenone; Glutamic Acid; Heart Rate; Hypertension; Infusions, Intravenous; Infusions, Intraventricular; Kynurenic Acid; Male; Mineralocorticoid Receptor Antagonists; Paraventricular Hypothalamic Nucleus; Rats; Rats, Wistar; Receptor, Angiotensin, Type 1; Receptors, Glutamate; Receptors, Mineralocorticoid; Signal Transduction; Spironolactone; Tetrazoles

The conventional reporting of composite endpoints in clinical trials has an inherent limitation in that it emphasizes each patient's first event, which is often the outcome of lesser clinical importance. To overcome this problem, we introduce the concept of the win ratio for reporting composite endpoints. Patients in the new treatment and control groups are formed into matched pairs based on their risk profiles. Consider a primary composite endpoint, e.g. cardiovascular (CV) death and heart failure hospitalization (HF hosp) in heart failure trials. For each matched pair, the new treatment patient is labelled a 'winner' or a 'loser' depending on who had a CV death first. If that is not known, only then they are labelled a 'winner' or 'loser' depending on who had a HF hosp first. Otherwise they are considered tied. The win ratio is the total number of winners divided by the total numbers of losers. A 95% confidence interval and P-value for the win ratio are readily obtained. If formation of matched pairs is impractical then an alternative win ratio can be obtained by comparing all possible unmatched pairs. This method is illustrated by re-analyses of the EMPHASIS-HF, PARTNER B, and CHARM trials. The win ratio is a new method for reporting composite endpoints, which is easy to use and gives appropriate priority to the more clinically important event, e.g. mortality. We encourage its use in future trial reports.

Topics: Angiotensin II Type 1 Receptor Blockers; Aortic Valve Stenosis; Benzimidazoles; Biphenyl Compounds; Cardiac Catheterization; Cardiovascular Diseases; Clinical Trials as Topic; Endpoint Determination; Eplerenone; Heart Failure; Hospitalization; Humans; Matched-Pair Analysis; Mineralocorticoid Receptor Antagonists; Proportional Hazards Models; Risk Factors; Spironolactone; Tetrazoles

Mineralocorticoid receptor (MR) blockade is an effective treatment for hypertension and diabetic nephropathy. There are no data on the effects of MR blockade on diabetic peripheral neuropathy (DPN). The aim of this study was to determine whether MRs are present in the peripheral nerves and to investigate the effectiveness of MR blockade on DPN in streptozotocin (STZ)-induced diabetic rats.. Expression of MR protein and messenger RNA (mRNA) was examined in the peripheral nerves using Western blot analysis and RT-PCR. We next studied the effects of the selective MR antagonist eplerenone and the angiotensin II receptor blocker candesartan on motor and sensory nerve conduction velocity (NCV), morphometric changes and cyclooxygenase-2 (COX-2) gene and NF-κB protein expression in the peripheral nerves of STZ-induced diabetic rats.. Expression of MR protein and mRNA in peripheral nerves was equal to that in the kidney. Motor NCV was significantly improved by 8 weeks of treatment with either eplerenone (39.1 ± 1.2 m/s) or candesartan (46.4 ± 6.8 m/s) compared with control diabetic rats (33.7 ± 2.0 m/s) (p < 0.05). Sensory NCV was also improved by treatment with candesartan or eplerenone in diabetic rats. Eplerenone and candesartan caused significant improvement in mean myelin fibre area and mean myelin area compared with control diabetic rats (p < 0.05). COX-2 mRNA and NF-κB protein were significantly elevated in the peripheral nerves of diabetic rats compared with control rats, and treatment with eplerenone or candesartan reduced these changes in gene expression (p < 0.05).. MR blockade may have neuroprotective effects on DPN.

Topics: Angiotensin II Type 1 Receptor Blockers; Animals; Benzimidazoles; Biphenyl Compounds; Blotting, Western; Diabetes Mellitus, Experimental; Diabetic Nephropathies; Eplerenone; Male; Mineralocorticoid Receptor Antagonists; NF-kappa B; Peripheral Nerves; Rats; Rats, Wistar; Real-Time Polymerase Chain Reaction; Receptors, Mineralocorticoid; RNA, Messenger; Spironolactone; Tetrazoles

This study examined the role of the renin-angiotensin-aldosterone system (RAAS) in mediating cardiovascular and renal damage in spontaneously hypertensive rats (SHR) given salt excess. Since the circulating RAAS is inhibited in this model, it permits examination of the role of local tissue RAASs in mediating this injury. To this end, male 8-wk SHR were divided into 7 groups. The control group (C) received normal NaCl (0.6%) diet. All other groups were given 8% NaCl chow. In addition, group 2 was given placebo, group 3 the mineralocorticoid receptor blocker eplerenone (100 mg.kg(-1).day(-1)), group 4 the angiotensin converting enzyme inhibitor quinapril (3 mg.kg(-1).day(-1)), group 5 the angiotensin II type 1 receptor blocker candesartan (10 mg.kg(-1).day(-1)), and groups 6 and 7 eplerenone and either quinapril or candesartan. The treatments lasted 8 wk. Compared with controls, mean arterial pressure (MAP), renal blood flow, coronary flow reserve, minimal coronary vascular resistance, diastolic time constant, and maximal rate of ventricular pressure fall were all adversely affected by salt loading. Left ventricular mass and fibrosis as well as proteinuria were also markedly increased by salt overload. Eplerenone induced only slight changes, whereas quinapril and candesartan normalized all indexes except MAP. Combination therapy also normalized all indexes, including MAP. These data suggest that 1) cardiovascular and renal damage induced by salt excess in the SHR were not pressure dependent; 2) mineralocorticoids were only marginally involved in this model; and 3) local tissue generation of angiotensin II may be, at least in part, responsible for the other adverse effects.

Topics: Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Animals; Benzimidazoles; Biphenyl Compounds; Blood Pressure; Cardiomyopathies; Cardiovascular System; Eplerenone; Hypertension; Hypertrophy; Kidney; Male; Mineralocorticoid Receptor Antagonists; Quinapril; Rats; Rats, Inbred SHR; Receptors, Mineralocorticoid; Regional Blood Flow; Renin-Angiotensin System; Sodium Chloride, Dietary; Spironolactone; Tetrahydroisoquinolines; Tetrazoles; Ventricular Dysfunction, Left

The intermediolateral cell column (IML) of the spinal cord is an important area where sympathetic impulses propagate to peripheral sympathetic organs. ANG II and aldosterone are important components of the renin-angiotensin-aldosterone system (RAAS), which activate the sympathetic nervous system. Each is partly synthesized in the brain and plays a paracrine role in the regulation of blood pressure independently of RAAS in the periphery. Our purpose in the present study was to clarify the contributions of sympathetic preganglionic neurons in the IML (IML neurons) and the effects of ANG II and aldosterone on the sympathetic nervous system. To examine responses to ANG II and aldosterone, we intracellularly recorded 104 IML neurons using a whole cell patch-clamp technique in spinal cord slice preparations. IML neurons were classified into two types: silent and firing. Both neuron types were significantly depolarized by ANG II, and candesartan inhibited this depolarization. After pretreatment with TTX, firing neurons (but not silent neurons) were significantly depolarized by ANG II. Aldosterone significantly increased the number of excitatory postsynaptic potentials (EPSPs) in both neuron types, but this response disappeared after pretreatment with TTX. ANG II and aldosterone had no synergistic effects on the IML neurons. The silent neurons had large cell soma, and many more dendrites than the firing neurons. These results suggest that ANG II acts presynaptically and postsynaptically in IML neurons, while aldosterone acts mainly presynaptically. Thus, the physiological effects of these substances are likely to be transmitted via specific membrane receptors of IML and/or presynaptic neurons.

Topics: Aldosterone; Anesthetics, Local; Angiotensin II; Angiotensin II Type 1 Receptor Blockers; Animals; Autonomic Fibers, Preganglionic; Benzimidazoles; Biphenyl Compounds; Eplerenone; Excitatory Postsynaptic Potentials; Female; In Vitro Techniques; Male; Mineralocorticoid Receptor Antagonists; Patch-Clamp Techniques; Presynaptic Terminals; Rats; Rats, Wistar; Spironolactone; Synaptic Transmission; Tetrazoles; Tetrodotoxin; Time Factors

We recently demonstrated that aldosterone induces a non-genomic vasoconstrictor effect on rat coronary arterioles and that this effect was blocked by angiotensin II type 1 receptor (AT1) blockers. Intracellular transglutaminase enhances AT1 signalling by cross-linking AT1 homodimers. The purpose of this study was to confirm the AT1-dependency of the vasoconstrictor effect of aldosterone using AT1a knockout (AT1aKO) mice and to investigate the role of intracellular transglutaminase and AT1 dimerization in this effect.. The mesenteric arterioles (60-160 microm) were isolated from C57BL/6J (wild-type, WT) and AT1aKO mice, and the internal diameter was measured by video microscopy. Aldosterone (10(-13) to 10(-6) M), but not hydrocortisone, produced a dose-dependent vasoconstriction in WT mice; the maximal diameter change was -8.6 +/- 0.3% from the baseline (P < 0.001). This vasoconstrictor effect was unaffected by the mineralocorticoid receptor antagonist spironolactone or eplerenone, the AT2 antagonist PD123319, the glucocorticoid receptor antagonist RU486, or endothelium denudation. Aldosterone's vasoconstrictor effect was negligible in AT1aKO mice. The AT1 blockers valsartan or candesartan suppressed aldosterone-induced vasoconstriction in WT mice. The transglutaminase inhibitors cystamine and monodansyl cadaverine also suppressed the vasoconstrictor effect of aldosterone, without affecting the vasoconstrictor effect of angiotensin II in WT mice. AT1 dimer protein levels were increased in WT mesenteric arterioles treated with 10(-7) M aldosterone, and the transglutaminase inhibitor and AT1 blocker blocked this aldosterone-induced formation of AT1 dimer. Treatment with 10(-7) M aldosterone for 10 min increased the transglutaminase activity by 2.5 +/- 0.2-fold in cultured vascular smooth muscle cells and by 1.2 +/- 0.1-fold in the mesenteric arterioles. These increases were abolished by transglutaminase inhibitors.. Aldosterone produces a non-genomic, endothelium-independent vasoconstrictor effect by enhancing intracellular transglutaminase activity and presumably inducing AT1 dimer formation in mesenteric arterioles.

Topics: Aldosterone; Angiotensin II Type 1 Receptor Blockers; Animals; Arterioles; Benzimidazoles; Biphenyl Compounds; Dimerization; Eplerenone; Male; Mesentery; Mice; Mice, Inbred C57BL; Mice, Knockout; Mineralocorticoid Receptor Antagonists; Receptor, Angiotensin, Type 1; Spironolactone; Tetrazoles; Transglutaminases; Valine; Valsartan; Vasoconstriction; Vasodilation

Recently, aldosterone has been shown to activate local renin-angiotensin system in vitro. To elucidate the potential role of local renin-angiotensin system in aldosterone-induced cardiovascular injury, we investigated the effects of selective mineralocorticoid receptor (MR) antagonist eplerenone (EPL), angiotensin (Ang) II type 1 receptor antagonist candesartan (ARB), and superoxide dismutase mimetic tempol (TEM) on the development of hypertension, vascular injury, oxidative stress, and inflammatory-related gene expression in aldosterone-treated hypertensive rats. The increased systolic blood pressure and vascular inflammatory changes were attenuated by cotreatment either with EPL, ARB, or TEM. Aldosterone increased angiotensin-converting enzyme expression in the aortic tissue; its effects were blocked by EPL but not by ARB or TEM. Aldosterone also increased Ang II contents in the aortic tissue in the presence of low circulating Ang II concentrations. Aldosterone induced expression of various inflammatory-related genes, whose effects were abolished by EPL, whereas the inhibitory effects of ARB and TEM varied depending on the gene. Aldosterone caused greater accumulation of the oxidant stress marker 4-hydroxy-2-neonenal in the endothelium; its effect was abolished by EPL, ARB, or TEM. Aldosterone increased mRNA levels of reduced nicotinamide adenine dinucleotide phosphate oxidase components; their effect was abolished by EPL, whereas ARB and TEM decreased only the p47phox mRNA level but not that of p22phox or gp91phox. The present findings suggest that the Ang II-dependent pathway resulting from vascular angiotensin-converting enzyme up-regulation and Ang II-independent pathway are both involved in the underlying mechanisms resulting in the development of hypertension, vascular inflammation, and oxidative stress induced by aldosterone.

Topics: Aldosterone; Angiotensin II Type 1 Receptor Blockers; Animals; Antioxidants; Benzimidazoles; Biphenyl Compounds; Blood Vessels; Cyclic N-Oxides; Eplerenone; Gene Expression Regulation; Hypertension; Inflammation Mediators; Male; Models, Biological; Oxidative Stress; Rats; Rats, Sprague-Dawley; Receptor, Angiotensin, Type 1; Renin-Angiotensin System; Spin Labels; Spironolactone; Tetrazoles

We previously reported that a high-sodium diet activates the local renin-angiotensin-aldosterone system (RAAS) in cardiovascular tissues of Dahl salt-sensitive hypertensive (DS) rats. Angiotensin-converting enzyme 2 (ACE2) is a novel regulator of blood pressure (BP) and cardiac function. The effect of blockade of aldosterone or angiotensin II (Ang II) on cardiac angiotensinogen and ACE2 in DS rats is unknown.. The BP, plasma renin activity (PRA), plasma aldosterone concentration (PAC), heart weight, endothelium-dependent relaxation (EDR), and messenger RNA (mRNA) levels of collagen III, angiotensinogen, ACE, and ACE2 in the heart were measured in DS rats and in Dahl salt-resistant (DR) rats fed high or low salt diets. The rats were treated orally with or without eplerenone (100 mg/kg/d), candesartan (10 mg/kg/d), or both drugs combined for 8 weeks.. A high salt diet increased BP (140%), heart/body weight (132%), and collagen III mRNA levels (146%) and decreased PRA and PAC concomitant with increased expression of cardiac angiotensinogen mRNA and decreased mRNA levels of ACE2 in DS rats. Eplerenone or candesartan significantly decreased the systolic BP from 240 +/- 5 mm Hg to 164 +/- 4 mm Hg or to 172 +/- 10 mm Hg, respectively (P < .05). Eplerenone or candesartan partially improved heart/body weight and cardiac fibrosis, improved EDR and decreased cardiac ACE and angiotensinogen mRNA levels in DS rats. Candesartan increased ACE2 mRNA levels in the heart. Combination therapy normalized BP and further improved cardiac hypertrophy, fibrosis, and EDR.. In DS rats, blockade of aldosterone or Ang II protects cardiac hypertrophy and fibrosis by inactivation of the local RAAS in the heart.

Topics: Aldosterone; Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme 2; Angiotensinogen; Animals; Benzimidazoles; Biphenyl Compounds; Cardiomegaly; Endothelium, Vascular; Eplerenone; Fibrosis; Hypertension; Male; Mineralocorticoid Receptor Antagonists; Myocardium; Peptidyl-Dipeptidase A; Rats; Rats, Inbred Dahl; Receptor, Angiotensin, Type 1; Renin-Angiotensin System; RNA, Messenger; Spironolactone; Tetrazoles