Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.15.1 (ACE)
 18,300 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Since the discovery of the atrial natriuretic factor (ANF) an endocrine function has been attributed to the mammalian heart. This function may include definition of optimal conditions for efficient performance of the heart, e.g. by reduction of afterload in hypertension or of preload and afterload in heart failure. Plasma ANF levels were measured in various cardiovascular disease states and compared with those of controls and of patients with liver cirrhosis. Plasma ANF levels in hypertensive patients were sevenfold higher than in controls, and in patients with heart failure 40-fold higher than normal values. Small differences were detected between controls and patients with cirrhosis of the liver, in spite of the impaired renal sodium handling seen in cirrhotics. Plasma ANF levels were significantly correlated with haemodynamic parameters and were inversely related to the cardiac index. Treatment with an angiotensin converting enzyme inhibitor led to a significant decrease in plasma ANF levels in parallel with the haemodynamic improvement. Preliminary chromatographic analysis suggested differences in the structure of plasma ANF between normotensive and hypertensive subjects.
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PMID:Atrial natriuretic factor in plasma of patients with arterial hypertension, heart failure or cirrhosis of the liver. 294 36

Natriuresis induced by infusions of atrial natriuretic factor (ANF) in water-loaded rats typically occurred in time sequences ('peak-and-shoulder' patterns) with an overlap of two different natriuretic responses. The first response was abrupt, short-lived and potentiated by angiotensin converting enzyme (ACE) inhibition. The second response was a gradual onset of natriuresis which lasted only as long as the ANF infusion and was directly correlated to the level of arterial blood pressure. This phenomenon explains the apparent loss of responsiveness to ANF bolus injections during a late phase. Atrial natriuretic factor facilitated excretion of intravenous salt loads, and the effect was also observed with low salt doses (1 microgram/h) which were below threshold for natriuresis when given alone. The data available so far suggest that ANF, apart from its effect on collecting-duct permeability, interferes with several control and feedback systems involved in sodium input into the collecting-duct system.
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PMID:Observations on the natriuretic response to intravenous infusions of atrial natriuretic factor in water-loaded anaesthetized rats. 294 40

Atrial natriuretic peptide is rapidly degraded by a soluble, heat labile peptidase isolated from ventricular myocytes. Degradation of [125I]-ANP is antagonized by unlabelled ANP, bradykinin, glucagon, 1,10-phenanthroline, PCMB, EDTA and the bacterial antibiotic bacitracin, but not by phenylmethylsulphonyl fluoride, aprotinin, phosphoramidon, E-64, amastatin or the ACE inhibitor SQ 20881 and bradykinin potentiator C. In addition neither bovine serum albumin nor caesin afforded any protection against degradation. Peptidase activity was optimal at pH values above 8.5. The peptidase is likely to be of intracellular origin and may contribute to the extensive ANP degradative activity found in various ventricular muscle preparations.
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PMID:Degradation of [125I]-atrial natriuretic peptide by a soluble metallopeptidase isolated from rat ventricular myocytes. 296 71

Congestive heart failure (CHF) is not only reflected by such mechanical problems as forward- and backward failure, but it is also associated with a complex pattern of compensatory neuro-endocrine mechanisms, e.g., enhanced activity of both the sympathetic nervous system (SNS) and the renin-angiotensin-aldosterone system (RAAS); enhanced release of vasopressin from the pituitary gland; enhanced release of the atrial natriuretic factor (ANF) from the cardiac atria. These neuro-endocrine mechanisms not only operate as such but also display a complex pattern of mutual interactions. These mechanisms, though potentially beneficial short-term, may also be harmful when persisting during progression of the disease. For this reason they offer potential targets in the treatment of CHF besides the classical measures aimed directly at improving cardiac contractility. The following groups of drugs are discussed as therapeutic measures that suppress the aforementioned detrimental compensatory mechanisms: various types of vasodilator drugs; diuretics; beta 1-adrenoceptor blocking agents in low dosage; saralasin; ACE-inhibitors. So far, the enhanced release of vasopressin and ANF have not offered realistic new therapeutic targets in CHF, although their pathophysiologic issue is highly relevant.
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PMID:Compensatory changes of sympathetic tone, the renin-angiotensin-aldosterone system, vasopressin, and ANF as potential therapeutic targets in congestive heart failure. 297 94

Capillary hypertension is suggested to be the underlying cause of microvascular disease affecting the kidney, the retina, and other organs and tissues in diabetic patients and animals. Hyperglycemia causes an expansion of extracellular volume, which induces a vasodilatory response. Hemodynamic adaptation to vasodilation leads to an increase in intracapillary hydraulic pressure, which subsequently causes vascular damage. In experimental animals, restoration of capillary pressure to normal levels by ingestion of a low-protein diet or administration of an angiotensin I-converting enzyme inhibitor has been shown to prevent microvascular damage in the kidney, and dietary protein restriction limits injury in the retina as well. Atrial natriuretic peptide, which is secreted by atrial myocytes in response to volume expansion, may be involved in mediation of the hemodynamic adaptation (vasodilatory response) that results in diabetic microvascular disease.
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PMID:Influence of antihypertensive therapy on development and progression of diabetic glomerulopathy. 297 86

The hypotensive and hormonal effects of the angiotensin converting enzyme (ACE) inhibitor enalapril (10 mg twice daily) were compared with those of hydrochlorothiazide (25 mg twice daily), with the two drugs in combination and with placebo in 21 patients with essential hypertension. For each patient there were four randomised double-blind treatment phases, each of four weeks' duration, which comprised a 2 X 2 factorial experiment. All blood pressure parameters were reduced in the three active treatment phases compared to placebo (p less than 0.001). Supine mean blood pressures were 119 mmHg (placebo), 113 mmHg (hydrochlorothiazide), 108 mmHg (enalapril), and 98 mmHg (hydrochlorothiazide plus enalapril) (SEM 3 mmHg, ANOVA). Enalapril and hydrochlorothiazide were equally effective and well tolerated and their hypotensive effects were additive. Enalapril increased plasma renin activity (PRA), reduced plasma angiotensin II (AII) and aldosterone concentrations, and reduced ACE activity, whereas hydrochlorothiazide increased PRA, plasma AII, and aldosterone concentrations without altering ACE activity. With combination treatment the effects of enalapril on PRA and plasma AII concentrations were potentiated whereas those on plasma aldosterone concentration and ACE activity were additive. Atrial natriuretic factor plasma concentration in the placebo phase was 92 pg/ml and increased to 145 pg/ml in the hydrochlorothiazide phase (p less than 0.001, SEM 13 pg/ml), but there was no significant change in either the enalapril or combination phases.
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PMID:Effects of enalapril and hydrochlorothiazide on blood pressure, renin-angiotensin system, and atrial natriuretic factor in essential hypertension: a double blind factorial cross-over study. 302 94

1. In severe, familial hypertension, we have reported that the proportion of patients homozygous for the deletion allele of an insertion/deletion polymorphism of the angiotensin I-converting enzyme gene is markedly decreased in older age groups, suggesting that this genotype is associated with increased risk of premature death. The aim of the present study was to examine the relationship with age, of variants of other genes that encode proteins having an influence on the cardiovascular system. 2. Genotypes of 13 different variants at 12 relevant genetic loci were determined by either Southern blotting, followed by hybridization probing, or polymerase chain reaction techniques, as appropriate, using genomic DNA extracted from blood leukocytes. Genotype numbers were then assigned to the age categories of < 50, 50-59 and > or = 60 years. 3. Polymorphisms at the atrial natriuretic factor, antithrombin III, renin, angiotensinogen, neuropeptide-Y Y1 receptor, insulin, alpha 2-adrenoceptor, beta 1-adrenoceptor, growth hormone, low density lipoprotein receptor, insulin receptor and renal kallikrein gene loci were found to display similar allele frequencies in each age group of hypertensives, as well as in normotensive controls. 4. In conclusion, we were unable to detect any difference with age for a range of variants of genes whose products have cardiovascular significance, suggesting that, like most polymorphisms, they carry no selective survival advantage or disadvantage in the hypertensive and normotensive population groups studied.
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PMID:Frequencies of variants of candidate genes in different age groups of hypertensives. 788 87

Plasma concentration of two main cardiovascular substances - atrial natriuretic factor (ANF) and endothelin - were studied in control subjects (n = 21) under basal conditions and 90 minutes after oral administration of glucose. In hypertensive patients (n = 21) these determinations were repeated after 12 weeks treatment with an angiotensin I-converting enzyme inhibitor lisinopril (Prinivil, Merck Sharp and Dohme). While basal and post-glucose ANF concentrations did not differ in controls and hypertensive patients, a tendency to the higher endothelin levels was found in our group of essential hypertension when compared to normotensive subjects. Glucose loading did not change significantly ANF concentrations in any studied group but significantly lowered plasma endothelin in both controls (from 13 +/- 0.95 to 9.50 +/- 0.95 fmol/ml) and hypertensive patients (from 15.05 +/- 1.23 to 12.15 +/- 1.03 fmol/min). Treatment of hypertensive patients with lisinopril paradoxically increased concentrations of ANF (from 6.43 +/- 2.53 to 11.47 +/- 4.90 fmol/ml) and lowered that of endothelin (from 15.05 +/- 1.23 to 12.17 +/- 1.58 fmol/ml). From our findings we may suggest that the relative predominance of the vasoconstrictor (endothelin) over the vasodilator (ANF) humoral substances might participate in pathogenesis of EH and that the reversal of this disadvantageous ratio after lisinopril (increase of ANF and decrease of endothelin) might contribute to the blood pressure reducing effect of ACEI. The drop in plasma endothelin after glucose remains so far unexplained consequence of glucose loading in both control and hypertensive subjects.
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PMID:Plasma concentrations of some cardiovascular humoral factors in essential hypertension and their changes during the treatment with converting enzyme inhibitor lisinopril. 799 8

The aim of the study was to compare, in a rat model of congestive heart failure, the effect of captopril, a selective angiotensin-converting enzyme (ACE; EC 3.4.15.1) inhibitor, to that of alatriopril, a mixed inhibitor of ACE and atriopeptidase (EC 3.4.24.11), an enzyme implicated in the degradation of atrial natriuretic factor (ANF). Myocardial infarction was induced by ligation of the left coronary artery. Groups of rats received orally twice daily captopril (10 mg/kg), alatriopril (100 mg/kg) or vehicle. Treatments were started 18 to 20 h after ligation and continued for 4 weeks. Hypertrophic and hormonal changes reflecting congestive heart failure were assessed in rats with large infarcts by measuring the relative weight of cardiac tissues as well as by assaying ANF in heart and plasma and by measuring renin activity in plasma. Both treatments significantly reduced cardiac hypertrophy, but alatriopril showed a greater efficacy than captopril--the increase in relative heart weight reaching 38% with captopril and only 22% with alatriopril (P < .05). The hypertrophy of right ventricle was reduced by 47% with alatriopril and by 35% with captopril (N.S.), whereas the corresponding reductions for atria were 47% vs. 21% (P < .05). Both treatments prevented the ligation-induced increase of ANF level in the right ventricle. In contrast, plasma ANF level was significantly reduced after captopril but not after alatriopril treatment, a difference that probably reflects the protection of endogenous ANF in circulation resulting from atriopeptidase inhibition. Plasma renin was increased by 36-fold after captopril but only by 1.6-fold after alatriopril, a difference that presumably reflects the inhibition of renal renin secretion by endogenous ANF after alatriopril. These data suggest that enhancement of ANF levels in circulation via atriopeptidase inhibition magnifies the capacity of ACE inhibitors to prevent cardiac hypertrophy, and they show the potential therapeutic value of mixed ACE-atriopeptidase inhibitors in congestive heart failure.
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PMID:Effects of alatriopril, a mixed inhibitor of atriopeptidase and angiotensin I-converting enzyme, on cardiac hypertrophy and hormonal responses in rats with myocardial infarction. Comparison with captopril. 803 46

The consequences of hypertension and aging on cardiovascular structure and function are reputed to be similar, suggesting that blood pressure plays a role in the aging process. However, the exact relationship between aging, blood pressure, and the arterial structure-function relationship has not been demonstrated. To test the effects of aging, renin-angiotensin system, and pressure on the arterial wall, 20 normotensive male WAG/Rij rats were killed at 6, 12, 24, and 30 mo of age and compared with similar groups treated with an angiotensin (ANG)-converting enzyme inhibitor (ACEI), perindopril. Arterial function was determined by a systemic hemodynamic study and by in situ measurement of carotid compliance. Arterial wall structure was determined by histomorphometric and biochemical methods. Aging did not significantly modify blood pressure, but ACE inhibition decreased blood pressure significantly from 6 to 30 mo. Plasma renin activity decreased with age and increased with ACEI. Plasma atrial natriuretic factor increased with age and was significantly decreased with ACEI. Absolute and relative left ventricular weight increased with age, and ACEI delayed these increases. Arterial wall stiffness increased with age, as shown by a significant decrease in systemic and local arterial compliance and by an increase in aortic characteristic impedance. The increase in carotid wall compliance after poisoning of smooth muscle contractile function (KCN) was greater in young (6- and 12-mo old) than in old (24- and 30-mo old) rats. Chronic ACEI treatment increased basal carotid compliance values slightly and did not change KCN carotid compliance. The aortic and carotid luminal size increased regularly with age. Aging was associated without any change in absolute elastin content. In contrast, collagen content increased with aging. Aging was also associated with an increase in medial thickness. Medial thickening was mainly due to smooth muscle hypertrophy. Aging was associated with intimal proliferation, which became progressively thicker and collagen rich. ACEI treatment did not prevent aortic lumen enlargement but significantly postponed the increase in medial and intimal thickening. Biochemical determinations of the aortic wall components confirmed the morphometric data. In conclusion, the age-dependent large artery enlargement and stiffening were observed both in normotensive rats and in those rats whose blood pressure was lowered by ACEI. This suggests that aging and blood pressure affect arterial wall structure and function by different mechanisms.
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PMID:Effect of chronic ANG I-converting enzyme inhibition on aging processes. II. Large arteries. 804 14


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