Strenuous physical exercise causes transient proteinuria and renal hemodynamic changes: decrease of renal blood flow and to a lesser extent of the glomerular filtration rate, and an increase of the filtration fraction. However, the mechanisms of these modifications are still poorly understood. In order to elucidate them we performed maximal ...

This investigation was performed to assess the effect of treatment with an angiotensin-converting enzyme (ACE) inhibitor, ramipril, on human tissue renin levels. A total of 41 patients were studied (32 males and 9 females, aged 48-71 years). Twenty-two of these patients received up to 5 days treatment with the ACE ...

The mechanism of action of angiotensin-converting enzyme (ACE) inhibitors on urinary albumin excretion (UAE) in diabetic patients remains controversial. Sixteen type 1, insulin-dependent diabetics with incipient nephropathy received ramipril, a long-acting ACE inhibitor, at hypotensive doses (treatment A: 5 mg/day, n = 8) or at nonhypotensive doses (treatment B: 1.25 ...

In clinical pharmacology studies, cilazapril, after its bioactivation to cilazaprilat, was characterised as a potent, reversible angiotensin converting enzyme (ACE) inhibitor with a terminal half-life of 30 to 50 hours, which is consistent with saturable binding to ACE. Despite the arterial vasodilatation, only slight increases in heart rate occurred during ...

There is considerable interest in the ability of angiotensin-converting enzyme (ACE) inhibitors not only to lower blood pressure, but also to reverse hypertension-induced remodelling of the circulation. Recently published data would suggest that treatment of spontaneously hypertensive rats from an early age with ACE inhibitors will prevent the development of ...

The angiotensin-converting enzyme inhibitor enalapril is available for intravenous administration in the form of enalaprilat. Intravenous enalaprilat is indicated for the management of hypertension when oral therapy is not feasible. However, there are no reports of intravenous enalaprilat therapy exceeding one week in duration. We report the case of a ...

The antihypertensive effects of isradipine and captopril were studied in 231 patients with mild-to-moderate hypertension in a double-blind, randomized, between-patient trial. Treatment was started with 1.25 mg of isradipine or 12.5 mg of captopril twice daily which, if normotension was not obtained, was increased after 4 weeks to 2.5 mg ...

We have conducted a multicentre study in patients with mild to moderate hypertension. Lisinopril monotherapy, 10, 20, or 40 mg once daily (n = 35), was compared with captopril monotherapy, 25, 50, or 100 mg twice daily (n = 35). Blood pressure assessments were conducted using both office and 24-hour ...

In porcine aortic endothelial cells, the 21-amino acid peptide endothelin-1 (ET-1) is formed from a 39-amino acid intermediate big endothelin (big ET) by a putative endothelin-converting enzyme (ECE) that cleaves the 39-mer at the Trp21-Val22 bond. Because big ET has less than 1% of the contractile activity of ET-1, inhibition ...

In 33 patients with heart failure (NYHA II-III), the 24-h blood pressure rhythm was examined before and after the titration period of two ACE inhibitors. Blood pressure was measured by the oscillometric method using the blood pressure monitor 90202 from SpaceLabs, Inc. The measurements were taken from 06:00 to 22:00 ...

The angiotensin converting enzyme inhibitor captopril has been shown to cause resetting of the arterial baroreflex to a lower pressure without a change in gain. The present study was conducted to determine whether captopril altered the relationship between arterial pressure, heart rate, and renal sympathetic nerve activity in conscious quietly ...

1. The interaction between bradykinin (BK) and the renin-angiotensin system was studied in conscious, catheterized rats. 2. Intravenous injection of BK induced dose-dependent decreases in blood pressure in normotensive Wistar and Wistar-Kyoto rats and spontaneously hypertensive rats. Pretreatment with the angiotensin-converting enzyme (ACE) inhibitor captopril markedly enhanced the effect of ...

Cilazapril is a new nonthiol group containing angiotensin converting enzyme (ACE) inhibitor, which was designed by a computer-modelling technique in order to obtain a compound with high specificity and selectivity for the target enzyme. Cilazapril has been investigated in more than 4000 patients with all degrees of hypertension, as well ...

This paper reviews previous work done by my laboratory to investigate the effect of treatment with angiotensin-converting enzyme (ACE) inhibitors on blood pressure and small artery structure in spontaneously hypertensive rats (SHRs). First, the data confirm that ACE inhibitors have a persistent effect on blood pressure in SHRs when treatment ...

STUDY OBJECTIVE: Vasopressin, like angiotensin, has both vasoconstrictor and fluid retaining properties and therefore may make an important contribution to the pathogenesis of low output congestive heart failure. The study aimed to examine the relative importance of the renin-angiotensin system and vasopressin in an animal model of heart failure. DESIGN: ...

Additive combination studies of an angiotensin converting enzyme (ACE) inhibitor, captopril, and a renin inhibitor, ditekiren (U-71038), were carried out in conscious sodium-depleted and sodium replete cynomolgus monkeys. The agents elicited dose-additive hypotensive responses regardless of the order of drug administration in sodium-depleted monkeys. A dose-additive blood pressure response was ...

A system consisting of two mechanically coupled counter rotating bicycles, moving on the inner wall of a cylindrical space module, is proposed to prevent microgravity deconditioning. The two pedalling subjects generate a centrifugal acceleration vector (ac) simulating gravity. This last depends on the peripheral velocity (v) and on the radius ...

This multicenter, double-blind, parallel-group study compared the antihypertensive effects of two angiotensin-converting enzyme inhibitors, lisinopril and captopril, in 70 patients (35 lisinopril, 35 captopril) with mild-to-moderate essential hypertension. Doses of 10, 20, and 40 mg once-daily lisinopril or 25, 50, and 100 mg bid captopril were increased at biweekly intervals ...

The chronic effects of captopril on maternal hemodynamics and organ perfusion were investigated in 10 untreated and 10 captopril-treated pregnant spontaneously hypertensive rats by means of the radioactive-labeled microsphere technique. The normal decrease in blood pressure during gestation was prevented by reduction of litter size to two conceptuses on day ...

Benazepril HCl is an orally effective angiotensin converting enzyme (ACE) inhibitor previously shown to have significant acute hemodynamic benefits in patients with congestive heart failure. In this study, 21 patients with New York Heart Association Class III or IV congestive heart failure were treated with 2 to 15 mg of ...

Accumulating data indicate that tissue and systemic renin-angiotensin systems may coexist. Evidence supporting the existence of local regulatory systems derives from several sources. Firstly, it has been clearly demonstrated that all components of the renin-angiotensin system are detectable in the tissues of organs such as the brain, heart, lung, kidney, ...

Serum angiotensin converting enzyme (ACE) activity was determined in 46 children with congenital heart disease with normal and abnormal lung perfusion: (1) congenital heart disease with normal pulmonary blood flow (12 patients); (2) congenital heart disease with increased pulmonary blood flow (18 patients); (3) congenital heart disease with decreased pulmonary ...

The introduction of orally active angiotensin converting enzyme (ACE) inhibitors has revolutionized the treatment of hypertensive disorders and provided an effective alternative for the management of congestive heart failure (CHF). By interfering with the formation of angiotensin II, the active agent of the renin system, ACE inhibitors block the system's ...

A group of 55 black men with mild or moderate hypertension who were being treated with methyldopa, prazosin, and a thiazide diuretic in combination with sotalol, were studied before and after changing their treatment to captopril and a thiazide diuretic. The level of blood pressure control was similar in the ...

We compared the effects of sustained-release diltiazem and captopril on blood pressure control and lipid profile. Forty-eight patients with primary hypertension were included in this randomized, double-blind, crossover study and 43 completed the trial. Following a two-to four-week placebo run-in period, each patient initially received either diltiazem (60-180 mg twice ...

Results of uncontrolled studies suggest that the duration of action of an ACE inhibitor may be an important determinant of renal impairment when using these agents to treat patients with heart failure. To determine whether there is experimental evidence for this hypothesis, we compared the effects of intermittent (captopril, 25 ...

Oxygen-free radical intermediates/scavengers were measured in 43 patients with essential hypertension who, although under antihypertensive therapy (without angiotensin-converting enzyme inhibitors), still had high blood pressure values. Measurements were taken before and 30, 60 and 120 min after sublingual administration of 25 mg captopril. Both systolic and diastolic blood pressures were ...

The orally active angiotensin-converting inhibitors (ACE inhibitors) such as captopril and enalapril represent a significant therapeutic advance in the treatment of hypertension and congestive heart failure. Enalapril differs from captopril in several respects. It is a prodrug converted by hepatic esterolysis to the active (but more poorly absorbed) diacid, enalaprilat. ...

To develop a screening test for identification of renovascular hypertension, the blood pressure and plasma renin concentration responses to an oral test dose of captopril (6.25 mg) were studied in 47 hypertensive patients of mean age 61 years (range 34-85 years). Blood pressure was measured at 15-min intervals for 90 ...

The study of vasoactive agents in man often requires accurate measurement of short-lasting changes in blood pressure. Using a noninvasive photoplethysmographic device (Finapres), the authors investigated in normotensive subjects whether rapid increases in blood pressure can be assessed precisely by monitoring finger blood pressure continuously. Six volunteers were studied on ...

1. Angiotensin converting enzyme (ACE) from the rat heart and lung was studied by use of the radioligand [125I]-351A. 2. Displacement of the bound radioinhibitor [125I]-351A was used to assess the relative potency of six ACE inhibitors in rat heart and lung homogenates and estimate the binding association constant (KA). ...

In a double-blind 6 month trial, the cardiac effects of captopril and minoxidil, administered as third step treatments, were compared in 34 men with essential hypertension and diastolic blood pressure greater than 95 mm Hg who were taking 200 mg/day of metoprolol and 80 mg/day of furosemide. Average daily doses ...

Factor XIIIa (FXIIIa) catalyzes covalent crosslinking reactions of fibrin, affording the clot additional structural stability and resistance to plasmin-mediated degradation. Thus, inhibition of FXIIIa may render thrombi more susceptible to tissue-plasminogen activator (t-PA)-induced thrombolysis in vivo. We therefore examined thrombus weight and time to lysis in anesthetized rabbits undergoing arterial ...

In a randomized single-blind cross-over trial, the efficacy of digoxin, angiotensin-converting enzyme (ACE) inhibition by quinapril, and their combination on exercise tolerance, heart size (echocardiography), and neurohumoral systems was investigated in 19 outpatients with congestive heart failure (CHF) New York Heart Association functional class II and sinus rhythm. Baseline therapy ...

The hemodynamic effects of quinapril, a novel nonsulfhydryl-containing angiotensin-converting enzyme (ACE) inhibitor, were assessed in 10 patients with mild-to-moderate essential hypertension. Compared with placebo, quinapril (20 mg) administered twice daily for 4 weeks significantly lowered blood pressure by decreasing total peripheral resistance without producing tachycardia, an increase in cardiac output, ...

Hemodynamic and neurohumoral effects of intravenous captopril were studied in ten patients with severe chronic congestive heart failure (NYHA Functional Class III and IV). Incremental bolus doses of captopril, titrated to a maximum cumulative dose of 15 mg, were given at 10-minute intervals. Systemic arterial pressure, mean pulmonary capillary wedge ...

A comparative study of the effects of oral and sublingual captopril on the hemodynamics of the peripheral musculocutaneous vasculature was carried out on ten patients with essential hypertension. Both routes of administration of captopril lead to lower blood pressure and decreased regional resistance, and to an increased arterial blood flow ...

Blood pressure and pulse of 32 young healthy Nigerian volunteers were determined after they had been in an air-conditioned room from between 60 and 90 minutes. The same determinations were made at the same time of another day with air-conditioning switched off for the same period. The mean systolic blood ...

1. FPL 63547, in its active diacid form, was a potent inhibitor of rabbit lung angiotension converting enzyme (ACE) in vitro (IC50 0.51 nM). 2. In conscious normotensive dogs, FPL 63547 (10-300 micrograms kg-1 i.v.) produced prolonged, dose-related inhibition of plasma ACE activity and angiotensin I pressor responses, without affecting ...

The pressor response to norepinephrine (NE) was assessed in normal renin essential hypertensive patients before and after they were randomly assigned to receive in parallel groups of treatment a single dose of an angiotensin converting enzyme (ACE) inhibitor (captopril or lisinopril) or a prolonged therapy with lisinopril (30-45 days) or ...

A randomized double-blind study lasting 2 months was performed with either 25 mg captopril twice a day or 50 mg atenolol once a day in 125 patients with established diastolic hypertension (diastolic blood pressure greater than 95 mmHg) identified during a population screening programme of subjects aged less than 65 ...

The chemistry, pharmacology, pharmacokinetics, adverse effects, and dosages of the three currently available angiotensin-converting enzyme (ACE) inhibitors are reviewed. This class of agents effectively inhibits the conversion of angiotensin I to the active vasoconstrictor angiotensin II, a hormone that also promotes, via aldosterone stimulation, increased sodium and water retention. The ...

The beneficial effect of angiotensin-converting enzyme (ACE) inhibitors on myocardial mass and contractility in hypertension and, possibly, congestive heart failure (CHF) may be related to their ability to induce a decreased afterload. This has been assessed in four experimental models--renovascular hypertension, DOCA-salt hypertension, spontaneously hypertensive rats (SHR) and myocardial infarction ...

This paper reviews the haemodynamic effects of angiotensin-converting enzyme (ACE) inhibitors in hypertension, focusing on their ability to cause a fall in systemic vascular resistance, with no change in cardiac output and no reduction and even an increase in blood flow to vital organs such as the brain, the kidney ...

The purpose of this study was to investigate the effects of antihypertensive agents on blood pressure and the development of glomerular changes in salt-loaded, 5/6 nephrectomized spontaneously hypertensive rats (SHR). Thirty-two spontaneously hypertensive rats with 5/6 nephrectomy were divided into 4 groups: a control group (N = 8), and group ...

The acute haemodynamic effects of intravenous captopril were measured, and left ventricular function was analysed by radionuclide angiography in eleven patients with moderate to severe hypertension. All subjects received 1 mg captopril by bolus injection initially, followed at 10 minute intervals by 2 mg or 5 mg injections according to ...

Pharmacokinetic and pharmacodynamic variability largely account for interindividual differences in the response to antihypertensive drugs including angiotensin converting enzyme inhibitors. The factors determining the response to enalapril have been investigated in a placebo-controlled study in essential hypertension. The effects of placebo, the initial dose of enalapril, and long-term (1 and ...

Successful long-term treatment of hypertension must include consideration of individual patients' life-style interfaced with the potential for adverse drug events. In a postmarketing surveillance study, 30,515 patients received captopril monotherapy and were evaluated by 7792 physicians. Mean systolic and diastolic blood pressures were reduced 17 and 11 mm Hg, respectively. ...

We measured changes in plasma renin activity (PRA) and used angiotensin-converting enzyme blockade with captopril to evaluate the role of the renin-angiotensin system during hemorrhage and after opioid receptor blockade in conscious rabbits. The increase in PRA after nonhypotensive hemorrhage was not statistically significant. PRA increased sixfold after a hypotensive ...

Hypertensive patients prescribed captopril while attending a hospital hypertension clinic were studied, to identify the benefits of the drug, its adverse effects and factors predisposing to them. One hundred and eighty two patients were followed for a mean of 18 months; 24 received captopril alone, and 158 combinations of captopril ...