Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085580 (essential hypertension)
 14,686 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Plasma concentrations of atrial natriuretic factor (ANF) and cyclic guanosine monophosphate (cGMP) were measured in 10 patients with essential hypertension and 10 normotensive controls on the fifth day of a low (50 mmol/day), a medium (180 mmol/day) and a high (380 mmol/day) dietary sodium intake. Plasma ANF and cGMP concentrations were less on the low than on the high sodium intake. Values for ANF on the medium sodium intake were intermediate. In normotensive subjects cGMP concentrations did not differ significantly on the low and the medium sodium intake. As compared with the controls plasma concentrations of cGMP were significantly increased in hypertensive patients on all three levels of sodium intake, while ANF concentrations were identical in the two groups. Since cGMP is a second messenger to ANF the data suggest an increased cellular response to ANF in patients with essential hypertension.
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PMID:Changed cyclic guanosine monophosphate atrial natriuretic factor relationship in hypertensive man. 254 1

The purpose of this study was to evaluate the cardiovascular, renal and endocrine effects of human atrial natriuretic factor (ANF), infused at a rate of 0.8 microgram/min (about 4 pmol/kg/min) for three hours in normal subjects and patients with essential hypertension. This infusion rate was chosen to obtain a range of plasma ANF levels which can be generated by physiological manoeuvres and to reduce the likelihood of hypotension. Five patients and six healthy volunteers participated in the study. The infusion had to be prematurely discontinued in one patient and in one control because of hypotension with relative bradycardia. Blood pressure otherwise remained unchanged during infusion whereas heart rate rose transiently. Plasma ANF levels increased similarly during infusion from 8.9 +/- 2.6 to 23.9 +/- 6.4 pmol/l in patients and from 3.7 +/- 0.7 to 25.4 +/- 6.9 pmol/l in the controls, remained stable during the infusion, and decreased similarly in both groups after the infusion, with a half-life of 7 min. Plasma guanosine cyclic phosphate (cGMP) was augmented by about four-fold in both groups. In both groups, plasma aldosterone levels fell whereas plasma noradrenaline increased. The diuretic effect of ANF was similar in both controls and patients (1354 +/- 161 vs 1542 +/- 116 ml/3 hrs respectively), whereas its natriuretic effect was exaggerated in hypertensive patients (90 +/- 11 vs 62 +/- 9 mmol/3 hrs, P less than 0.05). In conclusion, this low infusion rate of ANF produced similar changes in plasma ANF, cGMP, aldosterone and noradrenaline levels but patients with mild essential hypertension demonstrated an exaggerated diuretic and natriuretic response to ANF infusion.
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PMID:Cardiovascular, renal and endocrine responses to low doses of atrial natriuretic factor in mild essential hypertension. 254 52

The known physiological adaptation of cardiovascular sensitivity to variations in angiotensin II (Ang II) levels would predict that the blood pressure (BP)-lowering effect of Ang II inhibition might be at least partly counterbalanced by enhanced Ang II reactivity. Therefore, factors other than Ang II inhibition per se may contribute to the antihypertensive mechanisms of angiotensin converting enzyme (ACE) inhibitors. In order to further investigate this, the body sodium-blood volume state as well as the pressor reactivity to infused Ang II or norepinephrine (NE) were assessed in 12 normal subjects and 16 patients with essential hypertension given a placebo, and after 6 weeks of intervention with enalapril (20-40 mg/day). Enalapril produced in both groups similar falls in plasma ACE activity (P less than 0.0001) and upright plasma aldosterone (P less than 0.01), and a rise in plasma renin activity (PRA; P less than 0.05). BP decreased from 156/107 +/- 3/2 (mean +/- s.e.m.) to 142/94 +/- 5/3 mmHg (P less than 0.001) in the hypertensives and from 118/84 +/- 4/2 to 111/73 +/- 4/3 mmHg (P less than 0.01) in the normal subjects. In the hypertensive patients only, the Ang II pressor reactivity relative to Ang II plasma levels during Ang II infusion was increased (P less than 0.01), while the NE pressor reactivity relative to NE plasma levels during NE infusion (P less than 0.01) as well as the exchangeable body sodium (-5%, P less than 0.001) were reduced significantly. Blood and plasma volume, levels of plasma atrial natriuretic factor and catecholamines, and the heart rate and its response to isoproterenol were unchanged in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Antihypertensive contribution of sodium depletion and the sympathetic axis during chronic angiotensin II converting enzyme inhibition. 255 35

Human atrial natriuretic factor (h-ANF) or its vehicle only, were infused at rates of 0.8, 1.6 and 3.2 micrograms/min over three successive 30-min periods, into five patients with mild essential hypertension and seven normotensive controls. Baseline (mean +/- s.e.m.) plasma ANF levels were 13 +/- 2 in patients and 8 +/- 1 pg/ml in controls. During the first period, plasma ANF and cyclic guanosine monophosphate (cGMP) levels increased in both groups without significant alteration of blood pressure, heart rate, diuresis, natriuresis or cGMP excretion rate. During the second period of infusion, plasma ANF levels increased up to 179 +/- 39 and 177 +/- 30 pg/ml in patients and controls and plasma cGMP concentrations increased X 5.0 and X 4.9, respectively; natriuresis increased X 2.4 in patients and X 3.1 in controls while urinary cGMP increased X 10.9 in patients and X 10.5 in controls. During the last period, three controls became hypotensive while blood pressure remained stable in the other controls and in the patients with essential hypertension. During this period, the increases in plasma ANF concentration, diuresis, natriuresis and urinary cGMP excretion were similar in both groups. However, the mean plasma cGMP concentration after 90 min infusion was significantly higher in hypertensive patients than in control subjects (30.7 +/- 3.3 versus 15.6 +/- 3.4 pmol/ml, P less than 0.05). The half-life and clearance of plasma ANF, upon discontinuation of the infusion, were similar in both groups. Our data suggest that patients with mild essential hypertension have enhanced increases in plasma cGMP but normal increases in diuresis, natriuresis and cGMP excretion following infusion of h-ANF at pharmacological rates.
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PMID:Effects of atrial natriuretic factor on natriuresis and cGMP in patients with essential hypertension. 282 96

Phenylephrine infusions enhance diuresis and natriuresis both in normal subjects and patients with essential hypertension, whereas they have an opposite effect on urinary aldosterone excretion, decreasing it in normal subjects and enhancing it in hypertensive patients. With the new knowledge concerning the atrial natriuretic factor (ANF), it seemed a strong possibility that in normal subjects phenylephrine infusions should exert its effect through the increased release of ANF, as suggested by in vitro studies. Phenylephrine infusions at high pressor dose (to increase diastolic pressure by 25 mmHg) in six healthy volunteers increased plasma ANF and cGMP and decreased plasma renin activity and aldosterone concentrations. Urinary volume, sodium, and cGMP excretion were also increased. Phenylephrine infusions at low pressor dose (to increase diastolic pressure by 12-15 mmHg), in healthy subjects and in five patients with mild essential hypertension, significantly increased plasma ANF concentrations and decreased plasma renin activity to the same degree in both groups. But, whereas in normal subjects plasma aldosterone decreased significantly, it increased in patients with mild essential hypertension despite the simultaneous rise in plasma ANF concentration.
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PMID:[Effects of phenylephrine on atrial natriuretic factor and the renin-aldosterone axis in normal patients and essential hypertensive patients]. 284 76

Plasma atrial natriuretic factor concentrations were measured in 44 patients with mild untreated essential hypertension and 48 normotensive controls. Mean venous plasma atrial natriuretic factor concentrations were 13.2 (SEM 1.5) and 13.0 (1.3) ng/l in the hypertensive patients and controls, respectively. Plasma atrial natriuretic factor concentrations were significantly correlated with age in both groups. Plasma atrial natriuretic factor concentrations were also measured during renal vein catheterisation in a group of 15 hypertensive patients; of these, eight had renovascular hypertension, and in all eight cases plasma atrial natriuretic factor concentrations were increased in the aorta and inferior vena cava. It is concluded that mild essential hypertension is not associated with increased plasma atrial natriuretic factor concentrations, whereas an age related increase in concentrations occurs in hypertensive and normotensive people.
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PMID:Plasma atrial natriuretic factor concentrations in essential and renovascular hypertension. 295 11

Atrial natriuretic factor (ANF) release is known to be regulated by distension of the atrial wall; other factors affecting ANF secretion have not yet been defined. In order to evaluate the effects of the reflex activation of the sympathetic nervous system on ANF plasma levels, in 11 patients with essential hypertension progressive deactivation of carotid baroreceptors was induced by 4-min graded increases in external neck tissue pressure. Carotid sinus hypotension induced progressive increases in blood pressure (BP), heart rate (HR) and forearm vascular resistance (FVR), while plasma renin activity and catecholamine concentrations did not change significantly. Despite the lack of changes in right atrial pressure during this manoeuvre, plasma ANF levels showed a progressive and significant reduction, which was correlated with the increase in FVR. Although a contribution by other factors cannot be ruled out, our data suggest that the reflex activation of sympathetic nervous system is associated with reduced ANF release, independent of changes in atrial pressure.
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PMID:Carotid baroreceptor unloading decreases plasma atrial natriuretic factor in hypertensive patients. 295 86

Hemodynamic and hormonal effects of two graded infusions of alpha-human-(1-28)-atrial natriuretic factor (0.5 microgram/kg prime followed by 0.05 microgram/kg per min for 20 minutes and by 0.1 microgram/kg per min for 20 minutes) were evaluated in 13 patients with mild to moderate essential hypertension. The lower dose of atrial natriuretic factor did not change significantly any of the considered variables, although it tended to reduce aortic mean blood pressure (from 132.6 +/- 5.3 to 125.5 +/- 4.6 mm Hg), cardiac index (from 3.67 +/- 0.2 to 3.54 +/- 0.18 liters/min per m2) and forearm vascular resistance (from 178.6 +/- 15 to 148.3 +/- 10 mm Hg/ml per s). The higher dose of atrial natriuretic factor significantly reduced mean aortic pressure (118.6 +/- 5 mm Hg), cardiac index (3.29 +/- 0.16 liters/min per m2) and stroke volume index (from 45.9 +/- 2.6 to 38.9 +/- 3 ml/m2) and slightly decreased pulmonary wedge pressure, whereas both total peripheral resistance and forearm vascular resistance were not modified. With this latter dose a reduction in aortic pressure was observed in all patients at the steady state, and this was associated with a fall in stroke volume index in 10 of the 13 patients and with a reduction in total peripheral resistance in only 6 patients. Heart rate and right atrial and pulmonary pressures did not change during infusion of atrial natriuretic factor. Plasma renin activity was only slightly reduced by atrial natriuretic factor, whereas plasma norepinephrine rose significantly (from 233 +/- 34 to 330 +/- 58 pg/ml).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hemodynamic and hormonal effects of atrial natriuretic factor in patients with essential hypertension. 295 31

We have measured the basal circulating level of atrial natriuretic factor (ANF) in hypertensive patients. Plasma ANF concentrations in 101 patients with mild untreated, essential hypertension and in 64 normotensive controls were 14.9 +/- 11.1 vs 11.9 +/- 7.7 pg/ml, p = NS respectively. Plasma ANF levels in the patients were correlated with mean arterial pressure (r = 0.35, p less than 0.001) and age (r = 0.38, p less than 0.001). Sixteen patients with uncontrolled hypertension despite treatment, had significantly higher plasma ANF levels (33.5 +/- 27.3 pg/ml, p less than 0.001). Forty other patients with hypertension were subjected to an abdominal aortography and a renal vein catheterism, in order to rule out renovascular hypertension. Of these subjects, 16 were without significant renal artery stenosis, 12 had left renovascular hypertension and 12 others right renovascular hypertension. Plasma ANF levels were maximal in the aorta and there were no differences between the ANF levels in the renal veins, whether the stenosis was on the right or left side. In conclusion, plasma ANF levels were not elevated in 101 untreated patients with mild essential hypertension. Together with the evidence of elevated intra atrial pressure in mild essential hypertension, as found by others, this suggests that ANF secretion might be impaired in this disease.
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PMID:[Determination of the atrial natriuretic factor in patients with essential and renovascular hypertension]. 295 39

Plasma concentrations of atrial natriuretic factor (ANF) were compared in normotensive subjects and subjects with untreated, uncomplicated essential hypertension (n = 21 pairs) matched for age, sex, and race. Plasma peptide values were slightly greater (45 +/- 3 vs 36 +/- 3 pg/ml; p less than 0.05) in the hypertensive group. On univariate analysis, age (r = 0.52, n = 47, p less than 0.001) and creatinine clearance (r = -0.30, n = 47, p less than 0.05) were significantly related to plasma ANF concentrations, but arterial pressure was not (r = 0.14, n = 47), in an extended group of normal subjects. In contrast, plasma ANF values were related to arterial pressure in both an extended group of subjects with untreated essential hypertension (r = 0.54, n = 38, p less than 0.001) and in our total heterogeneous pool of hypertensive patients (r = 0.46, n = 79, p less than 0.001), but weak positive associations with age and inverse relationships with creatinine clearance were not statistically significant in either hypertensive group. Similar weak inverse relationships between plasma ANF values and renin-angiotensin-aldosterone system activity were found in both normal and hypertensive subjects.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Correlates of plasma atrial natriuretic factor in health and hypertension. 296 87


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