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)

Renal artery stenosis, particularly related to advancing atherosclerotic disease, is a common concern to internists seeing patients with worsening hypertension and deteriorating renal function. Understanding the hormonal and hemodynamic consequences of critical vascular lesions allows better selection of antihypertensive therapy. With the application of potent antihypertensive agents--especially those that block the renin-angiotensin system, such as ACE inhibitors or the soon-to-be-released angiotensin receptor antagonists--blood pressure control often is not the primary reason to consider renal revascularization. Instead, protection of renal function beyond a critical level of arterial stenosis is becoming the main indication for both percutaneous angioplasty and surgical revascularization. Both procedures pose hazards, so optimal management of the patient with renovascular hypertension depends on achieving a balance between the risks and benefits to the individual patient. It remains incumbent upon the internist to weigh the cardiovascular and cerebrovascular risks against both the gains in blood pressure control and the likely progression of renal compromise during the patient's lifetime. Improved understanding of the outcomes of medical therapy versus revascularization depends on future prospective studies.
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PMID:Renovascular hypertension. 807 Apr 20

ACE inhibitor challenged renal scintigraphic studies offer noninvasive means of evaluating patients for renovascular hypertension, and provide help in selecting patients who will benefit most from interventional procedures designed for alleviation of renal artery stenosis. These studies provide functional assessment of each kidney which also helps the vascular surgeons to plan which renal artery to repair first, when bilateral renal arteries are stenotic, prior to an abdominal aortic aneurysm repair. Vasotec challenged Tc99mMAG3 renal scintigraphy is one of such tests with several advantages over other similar methods, and appears to have a great potential of being a preferred scintigraphic study for evaluation of renovascular hypertension.
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PMID:Scintigraphic evaluation of renovascular hypertension. 812 34

Twenty-nine patients with unilateral renal artery stenosis or occlusion were investigated. The veno-arterial gradient (VA-gradient) of erythropoietin (EPO), haemoglobin oxygen saturation and plasma renin activity (PRA) was determined separately in each kidney before and 1 h after angiotensin converting enzyme inhibition (ACE-inhibition). The VA-gradient of EPO and of hemoglobin oxygen saturation were the same in the affected and unaffected kidney during basal conditions. During ACE-inhibition the VA-gradient of EPO disappeared on the affected side but not on the unaffected side. A fall in s-EPO after ACE inhibition was demonstrated in the renal vein on the affected side (-1.4 U l-1, p < 0.01), in the contralateral vein (-0.8 U l-1, p < 0.01) and in the aorta (-0.6 U l-1, p < 0.01). The O2-gradients were reduced on both sides after captopril, from 10.8-7.5% (p < 0.04) on the affected side and from 10.8-9.0% (p < 0.04) on the contralateral. It is suggested that the stimulated renin-angiotensin system may be important for EPO production in the affected kidney in unilateral renal disease.
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PMID:Effect of captopril on the renal veno-arterial gradient of erythropoietin and oxygen in unilateral renal artery disease. 814 Mar 97

Thirty-five hypertensive patients, consecutively studied between 1986 and 1991, were retrospectively reviewed, to compare Technetium-99m (99mTc) DTPA renal scanning for renal artery stenosis with angiography. Ten patients were on chronic angiotensin converting enzyme (ACE) inhibitor medication and 20 underwent angioplasty of their stenoses. In patients not on ACE inhibitors the renal scan specificity was 83%, sensitivity 82%, negative predictive value 89% and positive predictive value 74%. In the 10 patients on ACE inhibitors the specificity was 67% (relatively more stenoses of < 50% were reported in this group), sensitivity 100%, negative predictive value 100% and positive predictive value 60%. Low levels of function (< 10 mL/min/1.73m2) in 9 kidneys did not militate against diagnoses that correlated well with angiography. Hence, renal scanning, particularly with ACE inhibition, is efficacious in the evaluation of possible renal artery stenosis. With a mean follow-up period of 29 months after percutaneous transluminal angioplasty (PTA), four patients had clinical improvement of hypertension control. Each had pre-PTA total glomerular filtration rates (GFR) of approximately 75 mL/min/1.73m2. No improvement was detected in cases with pre-PTA total GFR of < 50 mL/min/1.73m2. This may be the level of renal function below which PTA therapy or surgery will not provide benefit.
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PMID:Technetium-99m DTPA renography and angiography in renal artery stenosis of varying severity. 814 95

We investigated whether endothelial dysfunction might contribute to the exaggerated vasoconstriction that was induced by the administration of norepinephrine at the early stage of one-kidney, one-clip renal hypertension (1K1C) in rats. We also studied the role of the renin-angiotension system in this phenomenon. Male Wistar rats were killed 48 hours after the induction of renal artery stenosis or sham operation, and ring preparations of the thoracic aorta were obtained. The isometric contraction and relaxation of aortic strips produced by norepinephrine and acetylcholine, respectively, were recorded with a force-displacement transducer. The aorta of 1K1C rats showed a significantly (P < .05) exaggerated contractile response to norepinephrine as compared with that of control rats. Rubbing the endothelium and treatment with methylene blue or NG-monomethyl L-arginine acetate augmented the contractile responses to norepinephrine to a greater extent in control rats than in 1K1C rats; therefore, the responses of the groups did not differ significantly. In the second experiment, rats received 0.05% captopril, 0.02% enalapril, or 0.02% nicardipine in the drinking water for 1 day before and for 48 hours after the induction of renal artery stenosis or sham operation. The increased contractile responses of the aorta to norepinephrine in 1K1C rats were normalized to the level of the control rats by treatment with either captopril or enalapril but not with nicardipine. These results suggest that the endothelial dysfunction may contribute to the exaggerated norepinephrine-induced vasoconstriction observed in the 1K1C rats and that angiotensin I-converting enzyme inhibitors can restore the endothelial function.
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PMID:Exaggerated vascular response due to endothelial dysfunction and role of the renin-angiotensin system at early stage of renal hypertension in rats. 826 86

Plasma renin activity (PRA) and plasma concentrations of angiotensin II (AngII), atrial natriuretic peptide (ANP) and arginine vasopressin (AVP) were determined in the abdominal aorta and the renal veins before and 1 h after peroral ingestion of captopril 25 mg in 29 patients with arterial hypertension and unilateral renal artery stenosis or occlusion, in order to study the effect of ACE inhibition on single-kidney extraction ratio (ER) of PRA, AngII, ANP, and AVP, and on renal vein renin ratio (RVRR). PRA was increased, AngII and ANP were reduced, and AVP unchanged after captopril. On the affected side the negative ER or PRA (-1.03) and AngII (-0.28) and the positive ER of ANP (0.25) and AVP (0.14) were not significantly changed by captopril. On the non-affected side ER of AngII and ER of ANP were significantly reduced (ER of AngII, 0.41-0.00, ER of ANP, 0.29-0.17), but ER of PRA and ER of AVP were unchanged. RVRR was not significantly changed by captopril. RVRR was greater than 1.5 in 79% of the patients before captopril, in 82% after captopril, and in 93% either before or after captopril. It is concluded that captopril reduces ER of AngII and ER of ANP on the non-affected side but not on the affected side in unilateral renal artery disease with hypertension, and that the use of RVRR both before and after captopril improves the predictive value of RVRR with regard to the diagnosis of unilateral renal artery disease.
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PMID:Effect of captopril on renal extraction of renin, angiotensin II, atrial natriuretic peptide and vasopressin, and renal vein renin ratio in patients with arterial hypertension and unilateral renal artery disease. 827 17

Renal function scintigraphy under ACE inhibition has gained an important role in the diagnosis of renovascular hypertension. Using the radiopharmaceutical 99mTc-MAG3, 54 kidneys with angiographically verified renal artery status were evaluated with respect to the following scintigraphic parameters: intraparenchymal tracer transport, urine drainage, kidney size, and functional side-to-side ratio. In cases of decompensated renal artery stenosis, the typical scan finding using MAG3 was shown to be a distinct parenchymal nuclide retention in combination with a delayed appearance of the radiotracer in the pelvic system. In our patients, the visual impression of the renal sequential scans was superior to quantitative evaluation methods. Using these criteria in 43 patients with suspected renovascular hypertension, sensitivity and specificity were 89% and 88%, respectively. Bilateral positive findings were nonspecific; when excluding them from the study, specificity increased to 100%.
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PMID:[Evaluation criteria for captopril-kidney function scintigraphy using 99mTc-MAG3]. 829 28

In this study, the diagnostic value of renal function scintigraphy performed both without and with ACE inhibition has been evaluated using the new radiopharmaceutical 99mTc-MAG3. In cases of decompensated renal artery stenoses, the typical scan finding with this tubular excreted agent was shown to be a distinct parenchymal nuclide retention in combination with a delayed appearance of the radiotracer in the pelvic system. Using this criterion in 43 patients with suspected renovascular hypertension, sensitivity and specificity were 89 and 88%, respectively. Bilateral positive findings were non-specific; excluding them from the study, specificity increased to 100%. In renal insufficiency, captopril scans seem to be of reduced diagnostic value. Summarising our experiences, renal function scintigraphy using 99mTc-MAG3 without and with captopril was proved to be a reliable non-invasive method to detect or exclude haemodynamically relevant renal artery stenosis.
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PMID:[99mTc-MAG3-kidney function scintigraphy without and with captopril in the diagnosis of renovascular hypertension]. 835 61

A 10-year-old boy was admitted to our hospital with severe hypertension due to unusual aortic coarctation at the level of the diaphragm without renal artery stenosis. We made left interior thoracotomy and left para-rectal incision through extraperitoneal approach, and extra-anatomic bypass was established with a 16 mm knitted Dacron graft from the descending aorta to the infrarenal abdominal aorta, under a circulatory assist. Postoperatively, he complained of abdominal pain with residual hypertension and required an intensive anti-hypertensive treatment to avoid intestinal necrosis. Pressure gradient between upper and lower extremities disappeared 3 weeks after repair. High level of plasma renin activity still continued 4.5 months after surgery in spite of oral administration of beta blockade and ACE inhibitor.
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PMID:[Surgical treatment of congenital atypical coarctation of the aorta and postoperative management for hypertension]. 881 61

Atherosclerotic renal artery disease is an important secondary cause of hypertension. Currently, there is great interest in possible genetic determinants of cardiovascular disease. The ACE-D allele has been reported to be associated with increased risk of myocardial infarction as well as coronary re-stenosis after angioplasty. We therefore assessed whether this allele is also linked to renovascular disease by studying 56 Caucasian subjects with atherosclerotic renal artery stenosis and 74 age, sex and race matched control subjects. Genetic analysis for the ACE I/D polymorphism was performed on peripheral leukocytes using PCR techniques, including insertion-specific primers. The distribution of I and D alleles was: renal artery stenosis 8 II, 25 ID, 23 DD; and controls, 16 II, 41 ID, 17 DD. The frequency of the D allele in the renal artery stenosis group was significantly higher (D/total 71/112 = 0.66) than that of the control population [75/148 = 0.51; chi 2 = 4.17, P = 0.04; odds ratio 1.69 (95% CI 1.02 to 2.78)]. Our results suggest that the ACE-D allele may be associated with increased risk of vascular disease at sites other than the coronary circulation.
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PMID:Genetic risk for renal artery stenosis: association with deletion polymorphism in angiotensin 1-converting enzyme gene. 882 41


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