The purpose of this study was to evaluate if changes in vascular properties were related to baroreflex function in patients with primary aldosteronism. Twenty-three patients with primary aldosteronism, 22 essential hypertensive patients and 16 normal controls were studied. Continuous finger blood pressure (BP) was recorded by Portapres device during supine ...

Stroke-prone spontaneously hypertensive rats (SHRSP) on 1% NaCl drinking solution and Stroke-Prone Rodent Diet develop severe hypertension and glomerular and vascular lesions characteristic of thrombotic microangiopathy seen in malignant nephrosclerosis. We recently reported that spironolactone, a mineralocorticoid receptor antagonist, markedly reduced proteinuria and malignant nephrosclerotic lesions in these animals. This ...

The effects of the angiotensin II receptor blocker candesartan cilexetil on systemic and forearm haemodynamics and baroreceptor sensitivity were evaluated in this randomized, placebo-controlled, double-blind, crossover study. After a 4-week placebo run-in period, 22 patients with essential hypertension (diastolic blood pressure 100-114 mmHg) were randomized to receive either candesartan cilexetil ...

A 46-year old female nursing sister was admitted to three different hospitals because of blood pressure crises of 300/150 mmHg which occurred up to six times a day. The rises in blood pressure were accompanied by headache, tachycardia and outbreaks of sweating. Raised catecholamine concentrations were repeatedly measured in the ...

1. Recent animal evidence suggests that aldosterone, like angiotensin II, may possess detrimental autonomic modulating properties. Aldosterone has been shown to impair the baroreflex response in animal models. This study is designed to test the hypothesis that aldosterone directly attenuates the baroreflex in vivo in man.2. Fourteen healthy male volunteers ...

BACKGROUND: Despite cure of primary aldosteronism by surgical resection, hypertension persists postoperatively in 30% to 50% of patients. The aim of this study was to determine factors influencing long-term outcome of blood pressure after unilateral adrenalectomy for primary aldosteronism. METHODS: Records of 100 patients who underwent unilateral adrenalectomy for primary ...

1. In humans, the hypertensive effects of adrenocorticotropic hormone (ACTH) infusion are reproduced by intravenous or oral cortisol. Oral cortisol increases blood pressure in a dose-dependent fashion. At a dose of 80-200 mg/day, the peak increases in systolic pressure are of the order of 15 mmHg. Increases in blood pressure ...

Rapid nongenomic in vitro effects of aldosterone have been demonstrated recently in cultured vascular smooth muscle and endothelial cells. But there is, as yet, little evidence for corresponding in vivo effects. The present study thus investigates the rapid nongenomic effects of aldosterone on human cardiovascular function. In a double-blind placebo-controlled ...

Resection of pheochromocytoma is associated with potential risks of hypertensive crises and serious arrhythmias due to massive release of catecholamines from the tumor. We report our surgical experience with complete inferior vena caval isolation and extracorporeal charcoal hemoperfusion (IVCI-CHP), which were performed to prevent systemic exposure to catecholamines during surgical ...

The renin-angiotensin-aldosterone system plays an important role in large artery structure and blood pressure homeostasis. Among the genes coding for different components of this system, the aldosterone synthase (CYP11B2) gene could play an important role, but has been less investigated. We examined the role of two variations of the aldosterone ...

This study was conducted in normotensive and hypertensive subjects at the Vargas Hospital of Caracas. Normotensive subjects received, in a cross-over fashion, placebo, metoclopramide (MTC), or domperidone (DOMP), 40 mg of each drug, daily for 1 week. The first group of patients under placebo for 1 week received a single ...

A new syndrome, characterized by hypertrophy and hyperplasia of the juxtaglomerular apparatus of the kidneys, aldosteronism resulting from adrenal cortical hyperplasia, and persistently normal blood pressure is described in two patients. Overproduction of aldosterone could not be prevented by sodium loading or by administration of albumin intravenously; it was associated ...

Correction of the causes of secondary forms of hypertension usually restores blood pressure to normal. Hypothyroidism is a potentially important but overlooked cause of hypertension and restoration of euthyroidism with thyroxine therapy usually results in a substantial reduction in both systolic and diastolic blood pressure, especially in younger subjects. The ...

The aim of our study was to evaluate the relationships between endothelial function, small resistance artery structure, and blood pressure in patients with primary or secondary hypertension. Sixty subjects were included in the study: 9 patients with pheochromocytoma, 10 with primary aldosteronism, 17 with renovascular hypertension, and 13 with essential ...

A 40-year-old woman was admitted because of abdominal pain and diarrhea. She sometimes experienced paroxysmal hypertension, sweating, headache, and palpitation. Sigmoidoscopic findings showed well-demarcated diffuse mucosal edema, hyperemia, and easy touch bleeding from distal descending colon up to the splenic flexure area. Barium x-ray showed loss of haustral marking, thumb ...

A 49-year-old male was diagnosed as having primary aldosteronism at age 39, and he was treated with antihypertensive drugs. In 1995, a computed tomogram revealed a mass in the right adrenal gland. Radiological examinations and endocrinological data revealed the presence of a pheochromocytoma in the right and an adrenocortical tumor ...

We previously observed that, in subjects with essential hypertension, acute ouabain constricts the brachial artery diameter in the presence of spironolactone treatment, a finding that is not observed in the absence of aldosterone antagonist and therefore suggests a specific effect of aldosterone on the arterial wall. To evaluate whether aldosterone ...

OBJECTIVE: To compare the effect of ouabain on the blood pressure of rats with that of digoxin to find the evidences of the relationship between endogenous ouabain (EO) and development of hypertension. METHODS: Sprague-Dawley rats, which were divided into 3 groups, were infused with ouabain (23 x 75 micrograms.kg-1/day, i.p.), ...

As it has been suggested that parathyroid hormone (PTH) is implicated in the pathophysiology of essential hypertension, the effects of PTH(1-34) were assessed during infusion over 120 min in ten men with essential hypertension and in ten healthy men. Ionized calcium was kept constant by a clamping technique. Mean arterial ...

The aim of this study was to investigate the haemodynamic and endocrinological effects of noninvasive positive pressure ventilation (NIPPV). Eleven patients with oedema and recent hypercapnic and hypoxaemic worsening of a chronic respiratory insufficiency were included. Echocardiography, cardiac radionuclide assessment, blood catecholamines, salt and water handling hormones were measured at ...

Pheochromocytoma endures as a life-threatening disorder. In the absence of systemic hypertension, diagnosis may be difficult. We present a 46-year-old normotensive male with a history of presyncope. One of these episodes could be documented, and revealed symptomatic bradycardia suspicious of sinus node arrest. Due to hints of an elevated sympathetic ...

A patient with asymptomatic pheochromocytoma associated with catecholamine hypersecretion but no hypertension was treated by right laparoscopic adrenalectomy. The 63-year-old male patient was referred to us for treatment of an incidentaloma. The diameter of the adrenal tumor was 50 mm, and the peripheral blood nonrepinephrine level was 1.12 ng/ml (normal ...

Genetic defects in aldosterone biosynthesis and action affect blood pressure and electrolyte homeostasis. Aldosterone synthase deficiency, salt-wasting forms of congenital adrenal hyperplasia, and adrenal hypoplasia congenita all cause aldosterone deficiency, signs of which include hyponatremia, hyperkalemia, hypovolemia, elevated plasma renin activity, and sometimes shock and death. Conversely, the inappropriate regulation ...

OBJECTIVE: To study the effects of elevated intra-abdominal pressure upon renal function and the renin-angiotensin-aldosterone system. MATERIALS AND METHODS: Two groups of anesthetized, ventilated swine were studied. Intra-abdominal pressure was increased in experimental animals (n = 6) by incrementally instilling an isosmotic ethylene glycol solution into the peritoneal cavity until ...

BACKGROUND: Since hyperaldosteronism has been experimentally related to myocardial interstitial fibrosis, we investigated the effects of hypertension and excess aldosterone due to aldosterone-producing adenomas (APAs) on the heart. METHODS AND RESULTS: In 52 hypertensive individuals, we performed Doppler echocardiography for estimation of left ventricular (LV) wall thickness and dimensions, transmitral ...

Long term change of renin-angiotensin-aldosterone system (RAAS) induced by bed rest and its effects on cardiovascular system are still controversial. The purpose of this study was to obtain a general conclusion on these questions by analyzing our two 20-days horizontal bed rest experiments in past two years with 18 subjects. ...

The aim of this study was to investigate the effects of moxibustion at the meridian points BL-15 (Xin-shu) and BL-27 (Xiao-chang-shu) on renal function, systolic blood pressure, plasma levels of renin activity, aldosterone and atrial natriuretic peptide in spontaneously hypertensive rats. The results showed that urine volume increased significantly after ...

Left ventricular hypertrophy (LVH) is a common finding in hypertension and represents a detrimental outcome since it is associated with increased morbidity and mortality. For similar elevation of blood pressure the severity and type of LVH vary considerably in relation to several factors. Compelling evidence suggests that both the renin-angiotensin ...

Low renin hypertension (LRH), which accounts for 10-20% of patients with idiopathic "essential" hypertension, bears hormonal similarities to mineralocorticoid-induced hypertension, but elevated mineralocorticoid concentrations have not been found. Some patients with LRH have normal, rather than suppressed, plasma aldosterone concentrations, so that the ratio of aldosterone concentration to PRA (Aldo/PRA) ...

OBJECTIVE: To evaluate the relationship between certain humoral factors and left ventricular hypertrophy (LVH) in essential hypertension. PATIENTS AND METHODS: 62 essential hypertension (EH) patients (32 men, 30 women; mean age, 55 years) and 20 normotensive healthy subjects (10 men, 10 women: mean age, 52 years) were studied. EH patients ...

It has been proposed that several neurohumoral factors may be involved in the genesis of vascular structural changes (remodeling or hypertrophy) frequently observed in essential hypertension. Therefore, in this study we investigated vascular structural alterations of subcutaneous small resistance arteries in patients with secondary forms of hypertension. The study included ...

A minimum level of blood pressure is necessary for atherosclerosis to develop, even in the presence of hypercholesterolemia. Experimentally and clinically we have both examples of atherosclerosis in which hypercholesterolemia is the dominant pathogenetic factor and others in which hypertension prevails (BBWT). The pathogenetic role of hypertension may be direct ...

The aim of this study was to assess the blood pressure profile and vasoactive hormones in valvular aortic disease. Thirteen aortic stenosis and/or aortic regurgitation patients were matched with 13 control subjects. Ambulatory blood pressure monitoring was performed for 24 h. Arterial and venous plasma concentrations of renin, angiotensin II, ...

The temporal organization of blood pressure is mainly controlled by neuroendocrine mechanisms. The monoaminergic systems appear to integrate the major driving factors of temporal variability, but evidence also indicates a role of the hypothalamic-pituitary-adrenal, hypothalamic-pituitary-thyroid, opioid, renin-angiotensin-aldosterone, and endothelial systems as well as other vasoactive peptides. Although their hormonal secretions ...

The possibility that corticotropin (ACTH)-induced hypertension results from a direct central effect of the adrenocortical steroids released by ACTH was investigated in sheep. Using two approaches, steroid levels were increased in the brain while peripheral levels remained sub-pressor. The blood pressure response to intravenous infusion of a combination of 7 ...

We investigated the effects on the heart of hypertension due to the excess of aldosterone and suppression of the renin-angiotensin system caused by primary aldosteronism with M-mode echocardiography and transmitral Doppler flow velocity measurements. We studied 34 consecutive patients with primary aldosteronism and 34 with essential hypertension individually matched for ...

In uninephrectomized rats on 1% NaCl solution to drink, aldosterone (0.75 micrograms/h subcutaneously for 8 weeks) raises blood pressure and causes marked interstitial and perivascular cardiac fibrosis, effects not seen in animals on a low salt intake. In extending these initial findings, we have shown that cardiac fibrosis (i) is ...

BACKGROUND: Primary aldosteronism (PA) is a rare but potentially curable cause of hypertension. Between October 1982 and November 1994, 30 patients of PA received unilateral adrenalectomy with a long-term follow up (mean:60.3 months). Nineteen (63.3%) cases were cured (Group 1); 11(36.7%) cases were improved (Group 2). The purpose of this ...

The major antihypertensive effect of losartan, a nonpeptide angiotensin II antagonist, is thought to be due to inhibition of the pressor effects of angiotensin II. It is possible, however, that losartan alters the synthesis of vasodilator or vasoconstrictor prostaglandins (PG), thus contributing to its antihypertensive effect. Sixteen postmenopausal women with ...

OBJECTIVE: Reduced baroreflex sensitivity has been reported in several kinds of human hypertension. However, the nature of the baroreceptor-heart rate reflex in hypertension due to excess mineralocorticoid has never been fully explored. PATIENTS AND METHODS: Thirty patients with primary aldosteronism, 60 patients with essential hypertension (World Health organization stages I ...

Uninephrectomized rats maintained on 1.0% NaCl to drink and infused with aldosterone (0.75 microgram/h) for 8 wk have previously been shown to develop hypertension, cardiac hypertrophy, and cardiac fibrosis. In the present study we have shown that K+ supplementation (1.0% NaCl plus 0.4% KCl drinking solution) alters neither the interstitial ...

OBJECTIVE: To determine whether the central nervous system has a pressor or a depressor role in glucocorticoid-induced hypertension. METHODS: Intracerebroventricular dexamethasone or its receptor antagonist, RU 38486, was administered in 20 trained conscious dogs. In addition, intracerebroventricular RU 38486 was administered in dogs treated with oral dexamethasone. RESULTS: Intracerebroventricular dexamethasone ...

Nine patients with mild or moderate essential hypertension were studied at the Vargas Hospital of Caracas, Venezuela. After antihypertensive treatment discontinuation, all patients were placed on placebo during a 1-week period, after which domperidone, a peripheral DA(2) dopaminergic blocker, was orally administered at the dose of 20 mg every 12 ...

A 31 year old hypertensive patient suffered from a fluctuation of blood pressure. Pheochromocytoma was suspected because of the clinical history, and extremely labile blood pressure but did not respond to therapy with alpha adrenergic blocking agent and normal excretion rates of catecholamine and vanilly mandelic acid (VMA). An enlarged ...

Factitious pheochromocytoma usually occurs in patients surreptitiously ingesting adrenergic medications. We encountered a case of factitious pheochromocytoma where in the subject mimicked hemodynamic (profound hypertension) and biochemical (plasma catecholamine elevation) manifestations of the illness by consciously altering autonomic function with Valsalva maneuver. Clues to this presentation included visible performance of ...

Previous studies have shown that symptom complex in patients with mitral valve prolapse syndrome (MVPS) may result from various forms of autonomic dysfunction. However, the interaction between adrenergic activity and renin release has not been studied. The purpose of this investigation was to assess changes in plasma renin activity (PRA) ...

The incidence of vascular complications in 224 patients with aldosterone-producing adenoma (APA) which was proven on adrenal surgery, was compared to that in 224 sex- and age-matched patients with essential hypertension (EHT). The incidence of cerebral hemorrhage was significantly higher (p < 0.05) in the patients with APA when compared ...

A disturbance of the autonomic cardiovascular function has been postulated in primary aldosteronism as a possible mechanism for hypertension. Using the method of spectral analysis of heart rate and blood pressure variability, the aim of this study was to assess sympathovagal interactions modulating cardiovascular function and baroreflex control in patients ...

BACKGROUND: The mineralocorticoid hormone aldosterone may be an important mediator of pathological ventricular hypertrophy and heart failure. Much of the evidence for this arises from experimental work in rat models of mineralocorticoid-dependent hypertension, and a pathological role in humans is still uncertain. SUBJECTS: Eleven subjects with glucocorticoid-suppressible hyperaldosteronism, a hereditary ...

The volume of regulating hormones (renin, aldosterone, arginine vasopressin and atrial natriuretic factor), electrolytes and creatinine concentrations, and blood pressure were measured in two different four-week experimental protocols: respectively -6 degrees head-down bed-rest (5 subjects) and confinement (6 subjects). We observed a significant increase (P < 0.01 at D2 vs ...