Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.23.15 (renin)
 35,795 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of hypoxia on plasma atrial natriuretic factor (ANF), plasma renin activity (PRA), and plasma aldosterone concentration (PAC) was evaluated during 2 h of treadmill exercise at 2 km/h, 0 grade at sea level. Six male subjects exercised on 2 separate days during normoxia (21% O2) and hypoxia (13.3 +/- 0.3% O2). No significant changes in ANF or PRA occurred during either normoxic or hypoxic exercise. However, PAC fell significantly during normoxic exercise (17.5 +/- 3.6 vs. 12.7 +/- 2.6 ng/dl, p less than 0.05) but not during hypoxic exercise. Serum potassium concentration fell during hypoxic exercise (5.0 +/- 0.1 vs. 4.4 +/- 0.1 mmol/l, p less than 0.05) along with bicarbonate (27.8 +/- 0.7 vs. 25.8 +/- 0.6 mmol/l, p less than 0.01). Between normoxic and hypoxic studies there was a significantly higher heart rate during hypoxic exercise (78 +/- 5 vs. 90 +/- 6 b/min, p less than 0.01). The major conclusion of this study is that hypoxia resulting in arterial oxygen saturations of 81 +/- 0.7% does not affect plasma atrial natriuretic factor levels during mild exercise in normal male subjects.
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PMID:Atrial natriuretic factor during hypoxia and mild exercise. 182 9

The cause of primary (essential) hypertension remains unknown, but a number of circulating hormones and endothelium-derived factors are probably involved. This review summarizes recent evidence on the roles of hyperinsulinemia, the renin-angiotensin system, atrial natriuretic factor, and three endothelium-derived factors--prostacyclin, endothelium-derived relaxing factor, and endothelin.
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PMID:Hormonal and local factors in hypertension. 182 31

The effects of volume loading on atrial pressures and dimensions, plasma levels of atrial natriuretic factor (ANF), and other neurohormonal variables were studied in 11 patients with normal hemodynamics with the patients in a supine -15 degree left decubitus posture by infusing 750 ml of normal saline solution over 30 minutes. Right and left atrial areas were measured by two-dimensional echocardiography. Plasma ANF level was sampled simultaneously from the pulmonary artery, aorta, and femoral artery and vein. At 30 minutes into the infusion, pulmonary capillary wedge pressure and right atrial pressure increased from 5.6 +/- 2.8 mm Hg (mean +/- SD) and 6.4 +/- 2.2 mm Hg to 10.2 +/- 3.2 and 9.5 +/- 2.2 mm Hg, respectively (both p less than 0.01). Left atrial area increased from 12.6 +/- 2.2 cm2 to 15.0 +/- 2.1 cm2 (p less than 0.05), whereas right atrial area did not change. Plasma ANF levels from all sampling sites increased significantly (e.g., 43 +/- 21 pg/ml to 71 +/- 62 pg/ml in the femoral artery, p less than 0.05). Plasma norepinephrine and renin levels were unchanged, whereas aldosterone level declined significantly. At 30 minutes after termination of the infusion, atrial pressures declined to baseline values in all patients. However, left atrial area remained significantly increased, and a trend for systemic arterial plasma ANF level to remain increased was seen. Plasma aldosterone level remained significantly suppressed.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Sequential changes in atrial pressures, dimensions, and plasma atrial natriuretic factor concentrations during volume loading in hemodynamically normal human subjects. 182 90

Atrial natriuretic peptide (ANP), plasma renin activity (PRA), plasma aldosterone and urinary fractional excretion of sodium (%FENa) were measured in 22 athletes before and after 1 h running. After exercise the hormones increased significantly, while %FENa decreased. In fact, the percent PRA increases resulted higher than the percent ANP increases with a significant inverse correlation. It is concluded that hemodynamic changes during strenuous and prolonged physical exercise lead to the inhibition of the natriuretic properties of ANP by stimulating the renin-angiotensin-aldosterone system, although a feedback mechanism of modulation between ANP and PRA seems to occur.
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PMID:Atrial natriuretic peptide and urinary sodium balance during physical exercise. 182 41

To evaluate the possible physiologic role of atrial natriuretic factor (ANF) in the observed dissociation of aldosterone secretion from the renin-angiotensin system during hypoxic exercise, 12 untrained men, ages 18 to 24, were studied on two separate days for 30 min during hypoxic (16% O2) and normoxic (room air) exercise on a bicycle ergometer. Workloads were adjusted to produce individual heart rates that remained within 70 to 75% of their previously measured maximum. Hemoglobin saturation decreased during hypoxia from 98 +/- 0.1% to 90 +/- 0.4% (P less than .01). Plasma aldosterone levels increased significantly (P less than .01) under both breathing conditions, yet were on average 36% lower during hypoxia than during normoxia (P less than .001). Plasma ANF levels increased during exercise under both conditions (P less than .01), yet levels were 45% greater during hypoxia than during normoxia (P less than .001). Plasma renin activity, adrenocorticotropic hormone, cortisol, potassium, and systolic blood pressure increased during exercise on both study days (P less than .01, compared to basal level), and showed no difference between normoxic and hypoxic conditions. Plasma pH was slightly higher during hypoxic exercise (P less than .05, compared to normoxia). We conclude that acute hypoxemia is a potent enhancing stimulus for ANF release during dynamic exercise and that ANF is probably a contributing factor in the dissociation of aldosterone secretion from the renin-angiotensin system under these conditions.
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PMID:Effect of hypoxic exercise on atrial natriuretic factor and aldosterone regulation. 182 70

The possible involvement of peripheral dopaminergic mechanisms in the action of atrial natriuretic peptides was investigated in 10 subjects by administering 200 micrograms h-ANP 99-126 intravenously for 30 min during treatment with 50 mg carbidopa, a peripheral inhibitor of dopamine synthesis, every 8 h, or during placebo. Atrial natriuretic peptide (ANP) infusion during placebo was associated with a significant increase of diuresis, natriuresis, kaliuresis, urinary noradrenaline, and dopamine excretion. Plasma aldosterone significantly decreased. Blood pressure was slightly reduced. The administration of carbidopa significantly reduced urinary dopamine excretion but did not modify natriuresis, diuresis, indexes of adrenergic and renin-aldosterone system activity, blood pressure, or heart rate, both in basal conditions and in response to ANP infusion. We conclude that the effects of exogenous ANP administration are independent from dopaminergic mechanisms that involve the synthesis of dopamine outside the central nervous system, particularly in the kidney.
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PMID:Renal and hemodynamic effects of atrial natriuretic peptide infusion are not mediated by peripheral dopaminergic mechanisms. 182 72

1. The haemodynamic and hormonal responses to N-nitro-L-arginine (NOLA), a potent inhibitor of nitric oxide biosynthesis in endothelial cells, were investigated in conscious sheep. 2. Mean arterial blood pressure (MAP), heart rate (HR) and cardiac output by thermodilution (CO) were measured in four oophrectomized ewes. Two other ewes were surgically implanted with aortic electromagnetic flow probes and an indwelling carotid arterial line for monitoring CO and MAP over 40 h. 3. After a control period, NOLA (10 mg/kg) was injected intravenously and MAP, HR and CO monitored and blood samples taken at intervals over the following 24 h. 4. NOLA increased blood pressure within minutes, from 76 +/- 4 to a maximum of 99 +/- 4 mmHg (P less than 0.001) at 6 h after injection. It remained elevated 24 h after injection. CO and HR fell but these falls were not sustained longer than 6 h. Calculated total peripheral resistance increased to a maximum of 2 h, but had returned to control levels 24 h after injection. There were no significant changes in plasma concentrations of renin, atrial natriuretic factor, vasopressin, noradrenaline or endothelin during the first hour. 5. NOLA may be a useful tool in understanding the role of the endothelium and nitric oxide in the control of blood pressure.
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PMID:Haemodynamic and hormonal effects of N-nitro-L-arginine, an inhibitor of nitric oxide biosynthesis, in sheep. 182 63

The pathophysiological role of atrial natriuretic factor in patients with chronic heart failure is still unclear. Plasma ANF levels are elevated in this condition, particularly in patients with severe left ventricular dysfunction and during acute exacerbations. Drug therapy, including diuretics, vasodilators and inotropes which reduce cardiac filling pressures also reduce plasma ANF levels. In the clinical setting the measurement of ANF levels may provide a useful means of assessing salt and water retention in patients with heart failure. Intravenous infusion of ANF to patients with heart failure causes a diuresis and natriuresis, a fall in filling pressures and possibly suppression of the renin-angiotensin aldosterone system. High bolus dosing with the peptide may reduce systemic vascular resistance resulting in hypotension, which markedly attenuates the renal effects. A new pharmacological approach in this area is the development of neutral endopeptidase inhibitors, which prolong the half-life of endogenous ANF and potentiate its effects. The therapeutic potential of ANF in heart failure has yet to be realised.
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PMID:Atrial natriuretic factor in chronic heart failure. 182 7

Atrial natriuretic peptide has been considered to be a major regulator in the body's water and salt homeostasis. Antagonizing those mechanisms leading to volume retention and overload (renin, angiotensin, aldosterone), ANP has been suggested to play a critical role in the pathology of certain diseases like renal failure, congestive heart failure or hypertension. In this regard, we measured ANP plasma concentration in normal healthy dogs and dogs with renal failure, congestive heart failure and Cushing syndrome. ANP levels were slightly decreased in dogs with Cushing disease (n = 9; 5.5 +/- 2 fmol/ml), increased in renal failure (n = 7; 16.2 +/- 5.8 fmol/ml, p less than 0.05) and markedly augmented in dogs with congestive heart failure (n = 14; 52.9 +/- 29.75 fmol/ml, p less than 0.01) as compared to healthy dogs (n = 6; 8.3 +/- 3.5 fmol/ml). Furthermore, characterization of the measured immunoreactivity (IR-ANP) revealed, that up to 50% of the IR-ANP in dogs with congestive heart failure corresponds to the ANP precursor molecule, not found in healthy subjects. This fact might present one possible explanation for the attenuated response to ANP in congestive heart failure. In addition, this finding may also serve a diagnostical purpose.
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PMID:[Diagnostic possibilities of ANP blood measurements in dogs]. 182 66

Calcium channel blockers have strong vasodilator, natriuretic and diuretic actions in normal and hypertensive subjects. The aim of this study was to evaluate the effect of diltiazem on renal function, renin-angiotensin-aldosterone axis (RAA) and atrial natriuretic factor (ANF) in patients with liver cirrhosis. Seven patients (3 females and 4 males) with a mean age of 56.3 +/- 11.1 years (36-68) entered the trial. All of the patients had HBV (6 cases) or HCV (1 case) related Child A (3 cases) or Child B (4 cases) liver cirrhosis proven by liver biopsy. Patients were given placebo for 15 days followed by p.o. diltiazem 30 mg t.i.d. for 15 days. Urinary volume, natriuresis, creatinine clearance, plasma renin activity (PRA), ANF and aldosterone (ALD) levels were determined after the washout period and during the first and second weeks of drug treatment. Urinary volume increased by 25-170% in 5 cases but this difference did not reach statistical significance. Slight increases in natriuresis occurred in some cases on the 3rd day of the trial but the overall results were not statistically significant (191.50 +/- 26.85 vs 204.07 +/- 39.83 mmol/l). Diltiazem induced no significant changes in PRA, ALD and ANF levels or creatinine clearance during the first or second weeks of the trial. There was a significant drop in the pulse rate on the first or second weeks of the treatment (p less than 0.01 and p less than 0.05, respectively). No significant changes were noted on mean arterial pressure (MAP).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of diltiazem on renal function in patients with liver cirrhosis. 183 38


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