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)

The development of hypertension is accompanied by rarefaction of arterioles and capillaries in both animal models and humans. Although many studies have examined the effects of antihypertensive therapies on hemodynamics, cardiac hypertrophy, and large vessel structure, the question of whether changes in microvascular density induced by hypertension can be restored by pharmacologic treatment has yet to be answered. We report a series of experiments performed in rats with renovascular hypertension induced by unilateral nephrectomy and renal artery stenosis (Goldblatt one-kidney, one-clip model). Animals were treated for 4 weeks, after renal artery clipping, either with an angiotensin converting enzyme inhibitor (perindopril [PER], 0.76 mg/kg/day), or with an indol derivative diuretic with specific vascular properties (indapamide [IDP], 0.24 mg/kg/day) or with the combination of both drugs at the same doses as during monotherapy. Coronary microvessel densities (arterioles and capillaries) were evaluated by double immunolabeling in nonserial cryostat sections of the left ventricular inner myocardium. After 4 weeks of hypertension (mean arterial pressure, 174+/-11 v 124+/-5 mm Hg in normotensive (NT) controls, P < .01), cardiac hypertrophy (+59%, P < .001) was associated with a significant increase in myocardial arteriolar density (+27%, P < .01), and a decrease in capillary density (-12%, P < .05). Treatment with PER prevented the increase in arterial pressure, heart weight, and arteriolar density, but did not significantly affect the low coronary capillary density in comparison with that measured in untreated hypertensive (HT) rats. Treatment with IDP preserved normal capillary myocardial density but did not significantly lower the blood pressure (BP) (169+/-9 mm Hg) and only slightly reduced the cardiac ventricular hypertrophy: - 14% v untreated HT (P < .05) and +37% v NT (P < .01). In the same way, IDP normalized the left ventricular capillary density in spontaneously HT rats (+18% v untreated rats, P < .01). The combination of both drugs, PER and IDP, at the same low doses as during monotherapy, resulted in normal levels of arterial pressure and complete normalization of cardiac hypertrophy and arteriolar and capillary myocardial densities. In conclusion, the results observed after PER suggest that blockade of the renin-angiotensin system could inhibit large coronary vessel growth but minimally affects the capillary density despite complete normalization of BP. Indapamide could have beneficial effect on myocardial capillary density. The combination of IDP and PER has additional effects and prevents the increase in BP and cardiac weight, and reverses microvascular rarefaction, specifically arteriolar and capillary densities.
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PMID:Coronary microvasculature alteration in hypertensive rats. Effect of treatment with a diuretic and an ACE inhibitor. 1120 83

On November, 1997, a 15-year-old boy visited our hospital because of headache, fever and arthralgia. He was treated with 5 mg/day of prednisolone thereafter. On October 21, 1998, he was admitted because of remittent fever and multiple arthralgia and diagnosis of juvenile rheumatoid arthritis (JRA) was made. He was also found to have hypertension of 210/110 mmHg, and soon developed ptosis of the eye, facial paresis and perceptive deafness of the right side. Cerebrospinal fluid showed protein of 98 mg/dl and mildly elevated IgG, IgA and IgM levels with normal cell count. Brain MRI examination revealed multiple cerebral lesions in the frontal, parietal and cerebellar areas on the right, whose cause was thought to be vasculitis. Renal angiography demonstrated a right renal artery stenosis, compatible with renovascular hypertension. He was treated with 60 mg of prednisolone per day, which brought about a satisfactory improvement of the above rheumatic and neurologic signs. On November 17, 1998, he received a follow-up study of MRI, which failed to show any cerebral lesions, supporting the effectiveness of prednisolone. An angiotensin converting enzyme inhibitor successfully normalized hypertension and renin activity in serum, although renal blood flow did not increase.
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PMID:[A case with juvenile rheumatoid arthritis who developed cerebral vasculitis and venovascular hypertension]. 1121 60

The consequences of a dietary n-3 PUFA supply was investigated on the blood pressure (BP) increase elicited by left renal artery stenosis in rats distributed in 3 groups (n = 8) fed for 8 weeks a semi-purified diet either as control diet or enriched diets (docosahexaenoic acid, DHA, or eicosapentaenoic acid, EPA). The PUFA intake induced large alterations in heart and kidney phospholipid fatty acid profile, but did not influence body weight, cardiac hypertrophy, renal left atrophy and right hypertrophy. Within 4 weeks, BP raised from 120-180 +/- 2 mm Hg in the control group, but only to 165 +/- 3 mm Hg in the n-3 PUFA groups. After stabilization of BP in the 3 groups, the rats received a short administration of increasing dose of perindopril. The lower dose (0.5 mg/kg) moderately decreased BP only in the control group. With higher doses (1, 5 and 10 mg/kg) BP was normalized in the 3 groups, with a higher amplitude of the BP lowering effect in the control group. A moderate n-3 PUFA intake can contribute to prevent the development of peripheral hypertension in rats by a mechanism that may involve angiotensin converting enzyme.
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PMID:Dietary n-3 polyunsaturated fatty acids affect the development of renovascular hypertension in rats. 1171 52

Renovascular hypertension is usually caused by atherosclerotic narrowing of the origin of the renal artery and is much more common than is thought among patients with peripheral vascular disease, carotid stenosis or heart failure. Renovascular hypertension must be distinguished from renal artery stenosis. In true renovascular hypertension, the kidney takes charge of the blood pressure and will do what it takes to push blood pressure high enough to force blood through the blocked artery. This can be diagnosed with functional tests that measure glomerular filtration rate before and after blockade of the renin-angiotensin system with angiotensin converting enzyme inhibitors or antagonists of the AT(1) subtype of the angiotensin receptor. There is insufficient data on which to make evidence-based recommendations on the management of renovascular hypertension. Only two randomised trials exist of angioplasty versus medical therapy and of these the larger was severely contaminated by angioplasty among the group initially assigned to medical therapy. Only one trial exists of angiotensin converting enzyme inhibition versus alternative medical therapy. The drugs that are most effective in medical management of renovascular hypertension--angiotensin converting enzyme inhibitors and angiotensin receptor-1 blockers--tend to be avoided because of fear of a very rare complication (acute renal failure in patients with severe stenosis of both renal arteries, or the artery to a single remaining kidney). This fear is misplaced not only because it is rare (< 5% of patients with renovascular hypertension) but because it is reversible and treatable by revascularisation. Patients with renovascular hypertension should be evaluated by nuclear medicine differential glomerular filtration rate, enhanced by blockers of the renin-angiotensin system. If medical therapy is ineffective or causes severe impairment of renal function, revascularisation is required. Some experts favour surgical revascularisation because of occasional angioplasty failure and the risk of deterioration of renal function after angioplasty.
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PMID:Treatment options for renovascular hypertension. 1193 44

The present study was undertaken to clarify the role of intrarenal angiotensin (Ang) II and its generating pathways in clipped and nonclipped kidneys of 4-week unilateral renal artery stenosis in anesthetized dogs. After 4 weeks, renal plasma flow (RPF) decreased in clipped and nonclipped kidneys (baseline, 59+/-3; clipped, 16+/-1; nonclipped, 44+/-2 mL/min; P<0.01, n=22). Renal Ang I levels increased only in clipped, whereas intrarenal Ang II contents were elevated in both clipped (from 0.7+/-0.1 to 2.0+/-0.2 pg/mg tissue) and nonclipped kidneys (from 0.6+/-0.1 to 2.5+/-0.3 pg/mg tissue). Intrarenal ACE activity was increased in nonclipped kidneys but was unaltered in clipped kidneys. An angiotensin receptor antagonist (olmesartan medoxomil) given into the renal artery markedly restored RPF, and dilated both afferent and efferent arterioles (using intravital videomicroscopy). Furthermore, in clipped kidneys, the elevated Ang II was suppressed by a chymase inhibitor, chymostatin (from 2.1+/-0.6 to 0.8+/-0.1 pg/mg tissue; P<0.05), but not by cilazaprilat. In nonclipped kidneys, in contrast, cilazaprilat, but not chymostatin, potently inhibited the intrarenal Ang II generation (from 2.4+/-0.3 to 1.5+/-0.2 pg/mg tissue; P<0.05). Finally, [Pro11-D-Ala12]Ang I (an inactive precursor that yields Ang II by chymase but not by ACE; 1 to 50 nmol/kg) markedly elevated intrarenal Ang II in clipped, but not in nonclipped, kidneys. In conclusion, renal Ang II contents were elevated in both clipped and nonclipped kidneys, which contributed to the altered renal hemodynamics and microvascular tone. Furthermore, the mechanisms for intrarenal Ang II generation differ, and chymase activity is enhanced in clipped kidneys, whereas ACE-mediated Ang II generation is possibly responsible for elevated Ang II contents in nonclipped kidneys.
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PMID:Differential regulation of elevated renal angiotensin II in chronic renal ischemia. 1210 35

Among the different causes of pulmonary edema, there are all the clinical situations with hydrosaline overload. A significant (> 70%) bilateral renal artery stenosis or a unilateral stenosis in the presence of a solitary kidney is one possibility. Recurrent acute pulmonary edema not fully explained on a cardiac basis is rather typical for such a disease in a cardiac patient with moderate renal failure aggravated when angiotensin converting enzyme inhibitors are used.
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PMID:[Renal artery stenosis: acute congestive heart failure as a possible cause]. 1214 63

The prevalence of RAAS in non-insulin-dependent diabetic patients ranges from 17 to 44%. The prevalence increases exponentially in the presence of several risk factors such as severe arterial hypertension, severe renal insufficiency, macroangiopathy, smoking, and insulin requirement. In diabetic patients, RAAS should be investigated in patients with severe arterial hypertension, repeated pulmonary oedemas, and renal insufficiency without any clear etiology associated with a mild proteinuria and/or with a renal insufficiency secondary to the administration of angiotensin converting enzyme inhibitors or angiotensin II receptors antagonists. Asymmetrical size of the kidneys should also prompt the physician with a suspicion of RAAS. There are several specific criteria, that may confirm the suspicion of a RAAS. Renal arteriography is still the goal standard for diagnosing renal artery stenosis.
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PMID:[How and when to search for a renal artery atheromatous stenosis in diabetic patients?]. 1214 7

High blood pressure as other factors of atherosclerosis is a well-known risk factor for development of peripheral arterial disease. A patient characterized by an isolated systolic hypertension and a low ankle/arm systolic blood pressure ratio very often presents coronary heart disease. Practising exercise (such as walking), stoping smoking and following an adapted diet are recommended. Hypertension treatment must be considered as a secondary prevention approach with a blood pressure normalisation as a target. All the different classes of antihypertensive drugs can be used, but with a marked preference for angiotensin converting enzyme (with caution for the renal artery stenosis risk) and for betablockers to improve the potential coronary heart disease (care is needed in the presence of severe peripheral arterial disease).
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PMID:[Hypertension and arteriopathy]. 1218 29

Angiotensin converting enzyme inhibition (ACEI) renography is the only imaging examination that tests directly for the presence of renovascular hypertension (RVH); other imaging examinations test for the presence of renal artery stenosis (RAS). The goals of ACEI renography are two-fold: 1) to detect those patients with hypertension who have renal artery stenosis as the cause of their hypertension and who would benefit from revascularization, and 2) to determine which hypertensive patients do not have renovascular hypertension and obviate the expense and risk of angiography and, potentially, revascularization. This review summarizes general components of renal scintigraphy (pretest voiding, hydration, patient position, relative uptake, time to peak height of the renogram curve, 20 min/max ratio, postvoid images, quality control) as well as those components specific to ACEI renography (choice of radiopharmaceutical, choice of ACE inhibitor, angiotensin II receptor blockers, diuretics, parenchymal mean transit time, monitoring of blood pressure, 1 versus 2 day protocols and omission of the baseline study). ACEI renography is highly accurate in patients with suspected RVH who have normal or near normal renal function. In this patient population, the sensitivity and specificity of ACEI renography for renovascular hypertension exceed 90%; angiography as an initial approach is not cost effective. Data from 10 studies evaluating cure or improvement in blood pressure in 291 patients undergoing revascularization showed the mean positive predictive value of ACEI renography to be 92%. When azotemic patients present with suspected RVH, as many as 50% of patients may have an intermediate probability ACEI renogram and the sensitivity of detecting RVH falls to approximately 80% even when intermediate and high probability tests are combined.
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PMID:Renovascular hypertension: nuclear medicine techniques. 1241 67

Atherosclerotic renovascular disease (ARVD) is common in the general population, and its prevalence increases with age. Parallel studies show it is also common in patients with diabetes. The widespread use of angiotensin converting enzyme inhibitors and angiotensin receptor antagonists for heart and kidney disease might therefore expose arteriopathic diabetic patients to potential harm if they had critical renal artery stenosis. This review looks at the natural history of ARVD in the diabetic and non-diabetic populations: while it is common, it only rarely leads to renal failure. Hence intervention to revascularize ischaemic kidney son the basis of radiological appearances alone may subject some patients to unnecessary therapy. Although untested by randomized trial, a policy of watchful waiting may be the simplest strategy for most diabetic patients with suspected ARVD, reserving angiography and angioplasty (usually backed up by a stent) for those with an abrupt decline in renal function and no other cause for renal deterioration. Future clinical trials may better define subgroups of patients who will truly benefit from renal revascularization.
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PMID:The impact of atherosclerotic renovascular disease on diabetic renal failure. 1242 24


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