losartan sleep

Intermittent hypoxia (IH) is believed to contribute to the pathogenesis of hypertension in obstructive sleep apnea through mechanisms that include activation of the renin-angiotensin system. The objective of this study was to assess the role of the type I angiotensin II receptor in mediating an increase in arterial pressure associated with a single 6-hour IH exposure. Using a double-blind, placebo-controlled, randomized, crossover study design, we exposed 9 healthy male subjects to sham IH, IH with placebo medication, and IH with the type I angiotensin II receptor antagonist losartan...

Peripheral chemoreflex activation has been considered the key drive for the overactivity of the sympathetic nervous system observed in some pathological conditions such as sleep obstructive apnea. In addition, increases in angiotensin-II-derived reactive oxygen species found in some autonomic regulatory brain areas have been implicated in hypertension. However, a link between oxidative stress and peripheral chemoreflex integration within the RVLM has never been investigated. Here, we tested the hypothesis that the pressor response induced by peripheral chemoreflex activation involves the angiotensin-II/AT(1)R/superoxide pathway within the rostral ventrolateral medulla (RVLM)...

The objective of this study was to investigate the effects of losartan (100 mg) plus hydrochlorothiazide (HCTZ; 25 mg) on nitric oxide (NO) production and blood pressure (BP) in "nondipper" severe hypertensive patients. Twelve hypertensive "nondipper patients" (6 of each gender) with sitting systolic/diastolic BP of 188.0 +/- 5.2/116.2 +/- 1.2 mm Hg were studied by 24-hour ambulatory blood pressure monitoring (ABPM) after daily administration of 100 mg losartan plus 25 mg HCTZ for a period of 12 weeks. Office and mean 24-hour, as well as mean awake- and sleep-time systolic/diastolic BP, serum NO levels, and urinary excretion of NO were measured after the placebo period (3 weeks) and after 12 weeks of therapy...

AIM: To estimate the efficacy of 8-week antihypertensive monotherapy in patients with arterial hypertension (AH) regarding the presence of obstructive sleep apnea syndrome (OSAS). MATERIAL AND METHODS: We analysed the results of 24-h blood pressure (BP) monitoring of 26 inpatients (mean age 54 +/- 2 years) with mild (n = 18) and moderate (n = 8) AH before and after 8 weeks of treatment with 5-10 mg amlodipine or 50-100 mg of losartan once daily to assess blood pressure profile parameters...

Angiotensin II and sodium balance affect the status of each other and both--either separately or together--can lead to an increase in blood pressure. They also can cause vascular and cardiac damage due to direct effects and effects mediated by the blood pressure increase. This paper reviews the important interactions among these three variables. Acute blood pressure elevation during sleeping but not during waking hours causes cardiac hypertrophy in rats. Similarly, lowering of blood pressure with an angiotension converting enzyme (ACE) inhibitor during sleep but not when awake causes regression of cardiac hypertrophy in rats with 2kidney (K)-1clip (C) Goldblatt hypertension...

This study was conducted in 19 patients with mild or moderate essential hypertension randomised open trial to evaluate the influence of potassium losartan dosed 50 mg per day on blood pressure, metabolic processes and left ventricular heart function. The following intervals of examination were accepted-at entry (before therapy with losartan) and then after 10 days; after 30 days and after 60 days of treatment. Mean values of arterial blood pressure and heart rate measured by conventional technics and obtained from 24-hour ambulatory monitoring data, biochemical results (serum levels of glucose, uric acid, creatinine, sodium, potassium, total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, bilirubin and serum activity of aminotransferases) and selected indices of left ventricular heart function were evaluated as intragroup differences using Student's paired t test...

OBJECTIVE: This study was performed to establish whether an angiotensin II antagonist modulates daytime sleepiness or performance. METHODS: The central effects of losartan (50 and 100 mg), as well as amlodipine (5 and 10 mg) and promethazine (10 mg), were studied in six healthy volunteers (aged between 20 and 27 (mean 24) yr). Digit symbol substitution, tracking, vigilance, immediate and short-term memory recall, complex reaction time, together with objective (daytime sleep latencies) and subjective measures of sleepiness, were measured 1...

Cardiac hypertrophy is common in hypertension but its development is influenced by angiotensin II, sodium intake aldosterone, and the time of day blood pressure (BP) is elevated. This study examined and compared cardiac hypertrophy in the 2 kidney-1 clip (2K-1C) and 1 kidney-clip (1K-1C) Goldblatt models of hypertension. Blood pressure was measured by telemetry in a selected group of rats. Rats were placed on a high (4%) or reduced (0.2%) salt intake and were given captopril (75 mg/kg per day) or losartan (10 mg/kg per day)...

We compared the effects of atenolol (50 mg), amlodipine (5 mg), enalapril (20 mg), hydrochlorothiazide (25 mg), and losartan (50 mg) given in once-daily oral doses on office and ambulatory blood pressures (BPs) in patients with hypertension and obstructive sleep apnea (OSA). Each of 40 randomized patients was treated in sequence with two of the five agents (balanced incomplete block design). Treatment periods lasted 6 wk and were separated by a 3-wk washout period. Changes in BP from baseline with the study substances were compared through analysis of variance...

One of the major manifestations of obstructive sleep apnea (OSA) is profound and repeated (episodic) hypoxia during sleep. Acute hypoxia leads to stimulation of the peripheral chemoreceptors, which in turn directly increase sympathetic outflow. It is believed that this increase in sympathetic outflow is directly responsible, at least in part, for the acute blood pressure (BP) changes seen in OSA. It is difficult however, to study the chronic effects of repeated episodic hypoxia (EH) in humans since the chronic cardiovascular changes may take many years to manifest...

Previous studies in several strains of rats have demonstrated that 35 days of recurrent episodic hypoxia (EH) (7 hours per day), with a fractional concentration of inspired oxygen that produces desaturation equivalent to the recurrent hypoxemia of sleep apnea, results in an 8 to 13 mm Hg persistent increase in diurnal systemic blood pressure (BP). Carotid chemoreceptors and the sympathetic nervous system have been shown to be necessary for development of this BP increase. Both renal artery denervation and adrenal demedullation block the BP response to chronic EH...

Effectiveness of Cozaar monotherapy (50 mg at 8 a.m.) was compared to that of Cozaar combination with melatonin (3 mg before sleep) in 21 patients with hypertension stage II (mean age 62 years). Clinical symptoms and hemodynamic parameters were evaluated with ECG and blood pressure monitoring. The findings were processed with statistical methods and Kosinor-analysis. Cozaar alone had moderate hypotensive and vasodilating effects, affected circadian rhythm of systolic and diastolic blood pressure, heart rate...

We examined the chronic effects of losartan (DuP 753), a novel orally active angiotensin II receptor antagonist, on blood pressure and renal function in eight hospitalized patients with essential hypertension. After a control period of 1 week, losartan was administered orally once a day for 2 to 4 weeks in increasing doses of 12.5, 25, 50, and 100 mg, until blood pressure in the supine position decreased more than 20 mm Hg (systolic) and 10 mm Hg (diastolic) (or 13 mm Hg in mean blood pressure). The average dose of losartan was 59...

We examined the chronic effects of MK954, a novel orally active angiotensin II receptor antagonist, on blood pressure and renal function in 8 patients with essential hypertension for 2-4 weeks. All patients, four men and four women, 48.0 +/- 15.3 year-old (mean +/- SD), were hospitalized and given normal sodium diet (NaCl 10 g/day). After a control period with placebo for one week, MK954 was administered orally at 8 AM every day. The initial dose of MK954 was 12.5 mg/day, then the dose was increased up to 100 mg/day until diastolic blood pressure fell below 90 mmHg...