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)

The presence of endothelin (ET) in tumor tissue and plasma of patients with pheochromocytoma was studied by radioimmunoassay. Immunoreactive (ir-) ET concentrations in 12 pheochromocytomas ranged from 66 to 253 fmol per gram wet tissue (gwt) (146 +/- 20 fmol/gwt, mean +/- SEM). These values were not significantly higher than tissue ir-ET concentrations of two primary aldosteronism (66 and 132 fmol/gwt) and three normal adrenal glands (71-120 fmol/gwt) (0.05 less than p less than 0.1). However, tumor tissue ir-ET concentrations in six of the 12 pheochromocytomas were higher than 132 fmol/gwt (the upper value of the control tissues). Sephadex G-50 column chromatography and reverse-phase high-performance liquid chromatography of pheochromocytoma tumor extracts showed a major peak eluting at an identical position to synthetic ET-1. Plasma ir-ET concentrations of pheochromocytomas (1.4 +/- 0.9 fmol/ml, n = 17) were not significantly different from those of patients with essential hypertension (1.0 +/- 0.7 fmol/ml, n = 20) and normal subjects (1.0 +/- 0.4 fmol/ml, n = 18) (0.05 less than p less than 0.1). This study has shown that high concentrations of ET-1 are present in tumor tissues of 50% of pheochromocytomas.
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PMID:Immunoreactive endothelin in pheochromocytomas. 172 1

In normotensive nonpregnant women (n = 23), the plasma concentrations of immunoreactive endothelin-1 (ir-ET-1) were not different from nonpregnant women with essential hypertension (n = 15): 3.6 (2.0-5.4) ng/L (mean, range) versus 3.8 (2.4-5.8) ng/L. In normotensive pregnant women (n = 25), the plasma level of ir-ET-1 was 2.1 (1.3-3.4) ng/L (p less than 0.01) lower than in normotensive nonpregnant women. Pre-eclamptic patients (n = 25) had elevated ir-ET-1 plasma levels of 5.0 (2.1-12.4) ng/L (p less than 0.001 for normotensive pregnant women, p less than 0.01 for nonpregnant women). The low level of ir-ET-1 in normotensive pregnant women may be explained by the increase in the distribution volume of ir-ET-1 during the course of pregnancy. Damage of vascular endothelium is a consistent morphological abnormality in pre-eclampsia. Elevated ir-ET-1 in plasma might be a biochemical marker of this abnormality and may contribute to the pathogenesis of pre-eclampsia.
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PMID:Plasma immunoreactive endothelin-1 in pregnant women with and without pre-eclampsia. 172 8

We developed six kinds of monoclonal antibodies against endothelin (ET)-1 recognizing different epitopes with high affinities (5 x 10(10) M-1 to 5 x 10(11) M-1). Using these monoclonal antibodies, we developed radioimmunoassays for ET-1 with different specificities. Cross-reactivities with ET-2 ranged from 80% to 100%, and those with ET-3 ranged from 3% to 60%. Patients with essential hypertension (n = 20) showed a significant elevation in the plasma ET-1-LI level compared with age-matched control subjects (n = 12) (30.1 +/- 1.4 pg/ml versus 18.5 +/- 0.9 pg/ml, p less than 0.01). The plasma ET-1-LI level in hypertensive patients in stages II and III (World Health Organization classification) was significantly higher than that in those patients in stage I. There was no significant correlation between the plasma ET-1-LI level and systolic blood pressure (r = 0.11), diastolic blood pressure (r = -0.13), or age (r = 0.24) in all patients studied who had essential hypertension. In the neutralization experiment, monoclonal antibodies attenuated ET-1-induced contraction of rat aortic rings and the pressor action of ET-1 in pithed rats in vivo. The present study demonstrates the elevated plasma ET-1-LI level in patients with essential hypertension. Monoclonal antibodies developed in this study can become powerful tools to investigate the pathophysiological significance of ET in essential hypertension.
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PMID:Application of monoclonal antibodies for endothelin to hypertensive research. 219 Sep 25

Normal endothelin 1/2 levels and their correlation with age were evaluated and compared with endothelin 1/2 levels in hypertensive patients. Plasma endothelin 1/2 (ET) levels were measured in healthy blood donors, mostly males, of mean age 36 +/- 8 years (36 subjects), subdivided into three groups: 17-30, 31-40 and above 40 years of age (41-59 yrs). Hypertensive patients (15 subjects) were subdivided into two groups: essential and nephrogenic hypertension. The normal ET levels in the three age groups (means +/- S.D.) were: 0.58 +/- 0.19, 0.62 +/- 0.31, and 0.80 +/- 0.28 fmol/ml, respectively. The average ET level for the whole normal population was 0.66 +/- 0.28 fmol/ml. Only the differences between the mean ET levels in the first and last group were significant (P < 0.05). The difference between the mean ET levels in smokers 0.71 +/- 0.28 fmol/ml (53% of total population) and non-smokers 0.65 +/- 0.28 fmol/ml, women and men, irrespective of age, was not found to be significant. The average ET level in all patients with hypertension (0.91 +/- 0.37 fmol/ml) was significantly higher than the average ET level in blood donors of the same age group (P < 0.05). Although patients with essential hypertension had elevated ET levels compared with control, the difference between the mean ET level in these patients (0.77 +/- 0.24 fmol/ml) and in the corresponsding control group (0.62 +/- 0.31 fmol/ml) was not significant.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Plasma endothelin 1/2 levels in healthy blood donors and in hypertensive patients: clinical application. 800 15

To assess the possible role of ET-1 in the pathogenesis of hypertension and salt sensitivity levels of immunoreactive endothelin-1 (irET-1) were measured in plasma and urine of 17 patients with essential hypertension and in 19 normotensive control subjects. Effects of alterations in dietary sodium content on urinary irET-1 levels also were assessed. Plasma levels of irET-1 did not differ between the hypertensives and normotensive groups (1.1 +/- 0.3 and 1.3 +/- 0.1 pg/ml). Urine samples of both groups contained high concentrations of irET-1. However, the mean daily urinary excretion of irET-1 in the hypertensives was less than one-third that in controls (29 +/- 3 vs. 109 +/- 21 ng/day, respectively, P < 0.01). Changing dietary sodium content in the hypertensives had no effect on mean irET-1 excretion. However, on either low, intermediate, or high salt diet, "salt sensitive" hypertensives had lower levels of the peptide than "salt resistant" patients (23 +/- 3 vs. 36 +/- 5 ng/day, respectively, P < 0.05). The data demonstrate a marked reduction in irET-1 excretion in patients with essential hypertension, despite normal plasma levels of the peptide. Since ET-1 has diuretic and natriuretic properties, the decreased renal excretion of ET-1 may be of relevance to the pathophysiology of hypertension and salt sensitivity.
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PMID:Urinary excretion rate of endothelin-1 in patients with essential hypertension and salt sensitivity. 816 45

An alteration in renal metabolism of endothelin may contribute to hypertension in the SHR and it has been shown that the excretion rate of endothelin is reduced in patients with essential hypertension. We measured plasma and urinary endothelin 1 (ET-1) in 20 untreated essential hypertensives with normal renal function, in eight normotensive healthy subjects, and in 13 hypertensive patients with primary renoparenchymal disease. Plasma ET-1 was higher (P < 0.01) in essential hypertensives (median 1.69, interquartile range 1.2-3.3 pg/ml) than in normal subjects (0.84, 0.37-1.10 pg/ml) but significantly less (P < 0.01) than in hypertensives with renoparenchymal disease (3.57, 1.45-9.52 pg/ml). ET-1 levels slightly correlated with diastolic pressure in essential hypertensives (r = 0.43, P < 0.05) and tended to be correlated with systolic pressure in hypertensives with renal disease (r = 0.47, P = 0.08). ET-1 excretion in essential hypertensives (137, 99-154 ng/24 h) and in normal subjects (120, 62-150 ng/24 h) was significantly lower than in renal hypertensives (191, 123-241 ng/24 h). The ET clearance/GFR ratio (ClET/GFR) was markedly reduced (30%, 21-67%) in essential hypertensives and substantially raised in renal hypertensives (164%, 86-314%) in comparison with normal subjects (83%, 35-94%). Since the ClET/GFR ratio should be 100% if all filtered ET-1 is excreted, the data indicate that ET-1 is synthesized at a reduced rate and/or broken down at an enhanced rate by the kidney in essential hypertension and confirm that there is a high ET-1 generation rate in remnant nephrons in hypertension secondary to renal disease.
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PMID:Urinary and plasma endothelin 1 in essential hypertension and in hypertension secondary to renoparenchymal disease. 853 21

Neuropeptide Y (NPY) has been recently characterized as a circulating vasoconstrictor peptide which is co-stored with noradrenaline in sympathetic neurons. To investigate the role of NPY concentration in hypertension we measured the circulating NPY, endothelin-1,2 (ET-1,2), atrial natriuretic peptide (ANP), aldosterone, plasma renin activity (PRA) and noradrenaline (NA) in patients with stable mild to moderate primary hypertension. Circulating levels of NPY, ET-1,2, ANP, aldosterone and PRA were measured with radioimmunoassay, NA by double-isotope radioenzymatic assay. There were significant increase in concentrations NPY, ET-1,2, ANP and NA in patients with moderate primary hypertension, and significant positive correlations between the plasma levels of NPY, ET-1,2 and NA.
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PMID:[Concentration of neuropeptide Y in serum of patients with primary hypertension]. 884 9

We assessed various aspects of endocrine function in patients treated for essential hypertension with manidipine chloride, a calcium channel blocker, to study the effects of this drug on several endogenous humoral factors, including human atrial natriuretic peptide (hANP) and endothelin 1 (ET), which influence vasoconstriction and blood fluid volume. The study included 19 patients with essential hypertension. All patients received manidipine chloride 10 mg/d for 24 weeks. After treatment blood pressure was normalized in all patients, and there were no significant changes in plasma renin activity or blood concentrations of vasopressin, hANP, ET, aldosterone, adrenaline, or noradrenaline. There was a statistically significant negative correlation between the change in ET levels and hANP levels before and after treatment. We also observed a statistically significant negative correlation between the change in systolic blood pressure caused by manidipine chloride and the change in hANP levels before and after treatment. These findings suggest that hANP and ET levels are systematically changed by manidipine chloride in patients with essential hypertension. We also speculate that changes in blood pressure may be closely related to levels of hANP in patients treated with manidipine chloride.
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PMID:Effect of manidipine chloride on various aspects of endocrine function, including plasma levels of endothelin-1 and human atrial natriuretic peptide, in patients with essential hypertension. 887 96

Cardiac function was evaluated in rest and after exercise on a cycloergometer in 20 patients with essential hypertension (EH) aged 14 to 19 years and 12 age-matched healthy volunteers. Selected parameters of ECHO examination and mitral flow were assessed, including SV, CO, CI, %SF, EF, LIVDd, IVSd, LVPWd, LVMI, total peripheral vascular resistance, ESS, velocity of wave E. A and E/A index. In all cases, serum ET1 and NPY levels were measured in rest and after exercise, before and after 6-month enalapril therapy. The ETI serum level in hypertensive patients did not differ from controls, while the NPY level was significantly higher in hypertensives. Exercise did not affect the ETI serum concentration, however, it did increase the NPY level. Enalapril therapy had no effect on serum peptide concentrations. Correlation of the ETI serum level with ECHO parameters, including CO, Cl, SV, LIVDd, LVPWd, %SF, TPRI and wave E velocity, as well as correlation of NPY concentration with LIVDd, LVPWd, LVMI, ESS and wave E and A velocity may suggest that these peptides influence left ventricle function and structure disturbances in children with EH.
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PMID:[Vasoactive peptides, endothelin 1 and neuropeptide Y, and total peripheral vascular resistance in children with essential hypertension]. 892 85

Vascular endothelial cells play a key role in cardiovascular regulation by producing a number of potent vasoactive agents, including the vasodilator molecule nitric oxide (NO) and the vasoconstrictor peptide endothelin (ET)-1. A dysfunction of the vascular endothelium has been implicated in the pathophysiology of a number of cardiovascular diseases, important among which is essential hypertension. Impairment of NO synthesis, or increased inactivation of NO by superoxide radicals, may account for the increased peripheral vascular tone associated with hypertension, as well as contribute to the clinical consequences of this condition, which include vascular hypertrophy, increased platelet and monocyte adhesion to the endothelium, atherosclerosis, myocardial infarction and stroke. Similarly, increased ET-1 synthesis, or increased smooth muscle sensitivity to ET-1, could account for many of the features of hypertension, including increased peripheral vascular tone and vascular hypertrophy. Modulation of endothelial function is, therefore, an attractive therapeutic option in the treatment of hypertension. Calcium antagonists have been shown to enhance the effects of NO, and inhibit those of ET-1, on vascular smooth muscle cells. In addition, calcium antagonists have antiatherogenic and antioxidant properties and could, therefore, prove to be useful therapeutic agents in preventing some of the important complications of hypertension. The long term effects on cardiovascular morbidity and mortality of the long-acting nifedipine gastrointestinal therapeutic system (nifedipine GITS) used in the treatment of essential hypertension are currently being investigated in the first multinational outcome study (INSIGHT) of an antihypertensive agent since the major studies of beta-adrenoceptor blockers or thiazide diuretics. The results of this study are awaited with considerable interest.
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PMID:Endothelial dysfunction and hypertension. 903 53


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