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 impact of treatment on prognosis of patients with chronic congestive heart failure depends not only on pharmacological therapy but also on nonpharmacological aspects of patient management. Patient compliance, life style changes, salt and fluid restriction, detailed patient information and measures of self control greatly affect therapeutic efficacy. Reasons for hospitalizations and emergency room visits: In an analysis of 82 admissions of patients for decompensated chronic congestive heart failure we found poor compliance with drug treatments or dietary instructions as causally related factors in 30 patients, uncontrolled hypertension in 22 patients, acute infection in 18 and acute myocardial ischemia in 18 patients. More than half of the patients had weight gain before decompensation, that had not been adequately answered by changes in medication. Inadequate patient information: Inadequate knowledge about necessary life style changes at the time of hospital discharge is often found in patients with chronic heart failure. Less than 50% of these patients remembered correctly the instructions on key issues of necessary life style changes and diet. Drug treatment of heart failure: Recent controlled drug trials have not gained enough weight in therapeutic decisions of physicians treating heart failure patients. While ACE-inhibitors have been shown to improve longevity in congestive heart failure only 6% of patients with heart failure are treated with these drugs, while 5% are treated with calcium antagonists which have not been proven to be of symptomatic or prognostic benefit and may be harmful as well in this disease. Inadequate dosage in patients with chronic renal failure or in elderly patients as well as inadequate choice of drugs lead to side effects in a considerable percentage of patients.
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PMID:[Effects of patient information, compliance and medical control on prognosis in chronic heart failure]. 182 Feb 95

To establish if the benefit of angiotensin converting enzyme inhibitor therapy in retarding progressive diabetic renal injury is due to a specific intrarenal effect of the systemic hypotensive effect, we studied the effect of long-term ramipril treatment on blood pressure, glomerular filtration rate, and urinary protein excretion in streptozotocin-diabetic spontaneously hypertensive rats. The hypotensive effect of ramipril was prevented by a high salt diet, which did not alter the degree of renal angiotensin converting enzyme inhibition. Three weeks after uninephrectomy and induction of diabetes, rats were allocated to three groups. Groups 1 and 2 were given 1% NaCl, whereas group 3 was given water as drinking solution. One week later, groups 2 and 3 received 0.4 mg/kg/day ramipril in their drinking solution, which was continued over a 2-month period. Ramipril produced a blood pressure fall only in water-drinking rats (group 3) despite a similar reduction in plasma and renal angiotensin converting enzyme activity in groups 2 and 3. Salt-loaded rats had a progressive increase in urinary protein excretion over the duration of study. Ramipril treatment prevented an increase in protein excretion only in animals given water and with a reduced systolic blood pressure. Glomerular filtration rate was similar in all three groups. Ramipril treatment improved animal survival independently of a reduction in blood pressure or an effect on proteinuria. Although it is possible that angiotensin converting enzyme inhibitors have specific intrarenal effects reducing progression of diabetic proteinuria, concomitant control of systemic blood pressure appears to be necessary to demonstrate a benefit.
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PMID:Salt blocks the renal benefits of ramipril in diabetic hypertensive rats. 182 92

Pharmacological blockade of the renin-angiotensin converting enzyme reportedly alters the heart rate (HR) power spectrum in conscious dogs, suggesting that these hormones contribute to the short-term regulation of arterial blood pressure. We tested this possibility using four independent procedures. First, HR power spectrum was determined in seven awake dogs before and after administration of enalaprilat (300 ng/kg), a converting-enzyme inhibitor. There were no significant changes in the average amplitude for the spectral peak between 0.003 and 0.1 Hz (i.e., the "low-frequency peak"). Second, the HR power spectrum was measured in 11 awake rabbits before and after treatment with deoxycorticosterone acetate (1 mg.kg-1.day-1) and salt (0.9% saline ad libitum) for 7 days to depress plasma renin levels. There were no significant changes in the amplitude of the HR power spectrum, although mean HR decreased from 206 +/- 3 to 184 +/- 4 beats/min after treatment. In the third experiment, another group of rabbits (n = 8) was tested after 2 wk on a low-salt diet to elevate plasma angiotensin levels and then after 2 wk on a normal salt diet. Once again there were no significant effects on the HR power spectrum. Finally, tranquilized dogs (n = 9) were subjected to sinusoidally varying lower body negative pressure at selected frequencies of 0.008-0.12 Hz. Tests were conducted in the control state and after administration of an angiotensin receptor antagonist (saralasin, 1 microgram.kg-1.min-1). Lower body negative pressure-induced fluctuations in arterial blood pressure were similar in both states. We find no evidence for the role of the renin-angiotensin system in the moment-to-moment regulation of arterial pressure and HR.
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PMID:Angiotensin II does not contribute to rapid reflex control of arterial pressure. 187 3

A number of studies based on animal models of both diabetes and renal insufficiency have shown that adequately reducing blood pressure attenuates the progression of glomerulosclerosis and decreases urinary protein excretion. Furthermore, compared with conventional antihypertensive therapy, angiotensin converting enzyme (ACE) inhibitors show a greater benefit in reducing these parameters. Nineteen published animal studies have investigated the effects of calcium antagonists on renal hemodynamics and glomerulosclerosis, but only three of them have evaluated the use of calcium antagonists with models of diabetes. Of six micropuncture studies based on a 1 5/6 nephrectomy model of renal insufficiency, five demonstrated reduced efferent arteriolar resistance, two showed reduced glomerular capillary pressure (PGC), and two showed significantly reduced proteinuria and glomerulosclerosis. Studies using nifedipine with both the unilaterally nephrectomized DOCA salt rat model and the 1 5/6 nephrectomy model demonstrated reduced proteinuria and glomerulosclerosis that was independent of reduced PGC. Two separate micropuncture studies of the spontaneously hypertensive rat model also found reduced efferent arteriolar resistance and PGC as well as proteinuria. Finally, studies of Dahl "salt-sensitive" rats showed an early decrease in glomerulosclerosis without a significant change in either proteinuria or glomerulosclerosis after five weeks. The results of eleven clinical studies of diabetic patients have been published; they showed divergent effects of calcium antagonists on renal function and urinary protein excretion. In the various animal models, the divergent renal hemodynamic and histologic effects reported for calcium antagonists may be largely due to the equality of blood pressure reduction, the varied baseline hemodynamic profiles, and the divergent status of the renin-angiotensin system.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Renal effects of calcium antagonists in diabetes mellitus. An overview of studies in animal models and in humans. 191 Jun 42

There is much circumstancial and some direct evidence in humans to suggest that a high consumption of salt predisposes communities and individuals to the development of essential hypertension. Restriction of salt intake in the diet lowers blood pressure in many subjects with high blood pressure and this fall in blood pressure is mediated in part by a diminished renin response to sodium restriction as hypertension develops. The effect of sodium restriction, like diuretics, is additive to many blood pressure lowering drugs, particularly those that inhibit the renin system such as beta-blockers and angiotensin converting enzyme inhibitors.
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PMID:Dietary salt intake and hypertension. 192 Dec 46

Bradykinin (BK) in an asanguinous salt solution was perfused through intact rat lung. BK concentration varied from 0.0015 to 89 microM. Below 17 microM, the amount degraded was greater than or equal to 90% of the dose. The BK fragment distributions expressed as a percentage of the BK dose degraded were constant. The BK fragments formed and percentage yields were Pro-Pro (2-3) 49%, Arg-Pro-Pro-Gly-Phe (1-5) 32%, Pro-Pro-Gly-Phe-Ser-Pro (2-7) 6%, Arg-Pro-Pro-Gly-Phe-Ser-Pro (1-7) 6%, Arg-Pro-Pro (1-3) 3% and residual BK 4%. Above 17 microM, the amount of BK degraded was not proportional to the dose. Captopril and enalaprilat inhibited BK degradation, and their maximum inhibitions were about 50% and 30%, respectively. The percentage yield of the 1-5 fragment was greatly reduced by both inhibitors, but the percentage yields of the 2-3 and 1-8 fragments were moderately increased. It was concluded that (1) the intact rat lung itself has a very large capacity to degrade BK in the range of 2 mumoles/min/kg body weight; (2) two major and several minor enzyme pathways exist to degrade BK; (3) the relative contributions of these pathways to overall BK degradation remain essentially constant over a bradykinin concentration range from 0.0015 to 17 microM; (4) ACE/kininase-II catalyzed hydrolysis is one of the major pathways but is not the single major route for BK degradation; and (5) the other major BK degradation pathway involves enzymes cleaving the Arg1-Pro2 and Pro3-Gly4 bonds of BK.
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PMID:Kinin metabolism in the perfused ventilated rat lung. I: Bradykinin metabolism in a system modeling the normal, uninjured lung. 200 2

Interpretation of renin-angiotensin blockade with angiotensin converting enzyme inhibitors is potentially confounded by their multiple effects. We used a selective renin inhibitor (enalkiren, A-64662) to explore the renal and endocrine effects of angiotensin II in healthy men. Each received 90-minute enalkiren infusions at 2-day intervals, on a low (10 mmol, 16 subjects) and high (200 mmol, 12 subjects) salt diet. Plasma renin activity, immunoreactive plasma angiotensin II and aldosterone concentrations, inulin, and p-aminohippurate clearance were measured by standard methods. Plasma renin activity fell at 0.1 micrograms/kg, but the threshold for biologic effect was 256 micrograms/kg, where plasma immunoreactive angiotensin II and aldosterone concentration fell, and renal plasma flow rose (p less than 0.01). The maximal renal vascular response (+152 +/- 23 ml/min/1.73 m2) occurred at 512 micrograms/kg (p less than 0.01). Diastolic and mean blood pressure fell modestly but significantly (p less than 0.05). Responses were limited on a high salt diet. We confirm that conventional plasma renin activity measurement is misleading in humans receiving a renin inhibitor. The renal vascular response to renin inhibition in this study appeared to substantially exceed reported responses to angiotensin converting enzyme inhibition, perhaps reflecting a crucial and relatively inaccessible intrarenal locus.
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PMID:Renal and endocrine responses to a renin inhibitor, enalkiren, in normal humans. 201 77

The relative contribution of the gut, liver, and lungs as sites of first-pass bioactivation (hydrolysis) of the orally administered ester prodrug, zofenopril calcium (SQ 26,991), to the active angiotensin converting enzyme (ACE) inhibitor, SQ 26,333, was determined. With a five-way study design, two dogs each received a single 1.6-mg/kg dose of zofenopril [as its soluble potassium salt (SQ 26,900)] via the following routes of administration: intraarterial, intravenous, intraportal, and oral. Each dog also received an equimolar oral dose of zofenopril calcium (1.5 mg/kg). Concentrations of zofenopril in plasma were quantitated with a GC/MSD assay. Extraction ratios (E) for zofenopril by the gut, liver, and lungs were calculated based on the ratios of the area under the curve (AUC) values of zofenopril in arterial plasma after administration by the various routes. As individual eliminating organs, the gut and liver each had a high intrinsic capability to hydrolyze zofenopril; E values ranged from 45 to 89%. The lungs were found to have low, but measurable, hydrolytic activity with estimated E values that ranged from 5 to 26%. Overall, about 95% of the orally administered dose of zofenopril calcium was hydrolyzed during the first pass. Because the prodrug is sequentially exposed to the gut, liver, and lungs, the contribution of the gut to the overall first-pass hydrolysis (ca. 87%) was estimated to be significantly greater than that of the liver (less than 10%) or lungs (less than 2%). Zofenopril was rapidly eliminated after parenteral administration; mean residence time values were 2 min and the elimination half-life values (intraarterial route only) were 9 min.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Sites of first-pass bioactivation (hydrolysis) of orally administered zofenopril calcium in dogs. 205 27

We examined the effect of angiotensin I (AI), without the effect of angiotensin II (AII) converted from AI, on the weight of the adrenal glands, adrenal corticosterone (B) and adrenal aldosterone under conditions where the renin-angiotensin system was suppressed, since a reduction in the size of the adrenal glands is often observed in DOCA/salt hypertensive rats. Sixty male Wistar rats fed on a 1% NaCl solution were divided into 6 groups as follows: a) Salt group: received sesame oil and vehicle, b) Salt + C group: received sesame oil and MK422 (0.14 mg/day), an angiotensin converting enzyme inhibitor (CEI), c) DOCA group: received DOCA (30 mg/week) and vehicle, d) DOCA + A group: received DOCA and AI (0.5 mg/kg/day), e) DOCA + A + C group: received DOCA and AI with MK422, and f) DOCA + C group: received DOCA and MK422. After 4 weeks, the rats were sacrificed to sample their blood and remove their adrenal glands. There was no significant difference in adrenal B among the groups apart from the DOCA + C group. Adrenal aldosterone was lower in the groups of DOCA/salt hypertensive rats than in the Salt group and Salt + C group. Furthermore, the DOCA + A + C group and DOCA + C group had lower adrenal aldosterone levels than the DOCA group and DOCA + A group.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Preventive effect of angiotensin I on weight reduction in the adrenal glands of DOCA/salt hypertensive rats. 208 30

As infection and malnutrition are steadily overcome in the developing world, cardiovascular disease loom large in the profile of morbidity and mortality in these societies. Hypertension, rheumatic heart disease and the cardiomyopathies are already taking their toll and atherosclerosis is certain to pose public health problems soon unless steps are taken now, through attention to known risk factors, to pre-empt or at least minimize its consequences. There are populations in developing countries among whom blood pressure does not appear to rise with age and in whom the prevalence of hypertension is very low. Studies of these communities and of migrant groups indicate that salt has an important effect on blood pressure. In spite of these observations, however, it is well known that black communities tend, on the whole, to show a higher prevalence of hypertension and more severe target-organ damage than white communities. Other distinguishing features are lower cholesterol, triglyceride and low-density lipoprotein fractions and a delayed response to a sodium load in black populations. Economic constraints limit the effective application of stepped-care therapy in the management of moderate to severe hypertension. Beta-blockers and angiotensin converting enzyme (ACE) inhibitors are not so effective in black communities unless combined with diuretics.
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PMID:Epidemiology of cardiovascular disease in developing countries. 209 92


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