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Query: UMLS:C0011881 (
diabetic nephropathy
)
10,836
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The renin-angiotensin system has two roles in clinical hypertension: its vasoconstrictor properties directly govern blood pressure, and its actions on arterial smooth muscle, connective tissue, and endothelial integrity affect cardiovascular prognosis. Additionally, the direct actions of angiotensin II on the function and structure of the heart and renal vasculature influence clinical events. Angiotensin-converting enzyme (ACE) inhibitors have produced functional and clinical outcome benefits in clinical trials of patients with congestive heart failure, systolic dysfunction after myocardial infarction, and
diabetic nephropathy
. Similar favorable trends have been noted in observational studies in hypertension. Because such enzymes as chymase can substitute for ACE, the ACE inhibitors may not completely block angiotensin II formation, although they enhance bradykinin accumulation and secondarily stimulate nitric oxide and vasodilatory prostaglandins.
Angiotensin II receptor
blockers (ARB) selectively block the angiotensin II type 1 (AT1) receptor that not only mediates the known effects of angiotensin II but, according to recent reports, might be responsible for sequestering angiotensin II molecules in renal and cardiac cells. Moreover, by increasing plasma concentrations of angiotensin II, the ARB stimulate the unblocked angiotensin II type 2 (AT2) receptors, which-if they exist in meaningful numbers in human hypertension-mediate additional vasodilatory and antiproliferative effects. The contrasting actions of these two classes of drugs might be clinically relevant. For example, they may have additive antihypertensive efficacy; they have differing effects on renal plasma flow; and in a small pilot study of patients with congestive heart failure, the ARB demonstrated an apparent advantage in survival. Ongoing clinical trials will try to determine whether the effects of ARB can equal or even exceed the beneficial effects of ACE inhibitors on cardiovascular prognosis.
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PMID:Interrupting the renin-angiotensin system: the role of angiotensin-converting enzyme inhibitors and angiotensin II receptor antagonists in the treatment of hypertension. 1061 71
Extensive clinical experience with angiotensin-converting enzyme (ACE) inhibitors in patients with renal disease has demonstrated efficacy in reducing blood pressure, proteinuria, and the rate of progression of renal disease. This is evident in both diabetic and nondiabetic nephropathy, particularly that associated with proteinuria. The ability of ACE inhibitors to stabilize renal function is not attenuated by more severe renal insufficiency, but greater caution with these drugs is necessary, as there may be drug accumulation and a greater propensity for an increase in serum potassium and creatinine levels. Both of these effects are self-limited and rarely require discontinuation of the drug. Increases in creatinine up to 20% are expected; greater increases are indicative of volume depletion or anatomic renal artery disease.
Angiotensin II receptor
blockers reduce blood pressure to a degree comparable to that achieved with ACE inhibitors, and like ACE inhibitors, they reduce proteinuria to an extent greater than what would be expected by blood pressure reduction alone.
Angiotensin II receptor
blockers are currently being evaluated in comparison with other therapies in two large clinical trials of non-insulin-dependent
diabetic nephropathy
with proteinuria to assess impact on the rate of progression of renal disease. Because of their antihypertensive/ antiproteinuric properties, it is likely they will provide some advantages over conventional drugs in protecting renal function. Early clinical experience with these drugs in patients with renal disease suggests that there might be a lesser incidence of functional renal insufficiency and hyperkalemia compared with ACE inhibitors.
...
PMID:Are drugs that block the renin-angiotensin system effective and safe in patients with renal insufficiency? 1061 72
Angiotensin II receptor
blockers (ARBs) represent a new class of effective and well tolerated orally active antihypertensive agents. Recent clinical trials have shown the added benefits of ARBs in hypertensive patients (reduction in left ventricular hypertrophy, improvement in diastolic function, decrease in ventricular arrhythmias, reduction in microalbuminuria, and improvement in renal function), and cardioprotective effect in patients with heart failure. Several large long-term studies are in progress to assess the beneficial effects of ARBs on cardiac hypertrophy, renal function, and cardiovascular and cerebrovascular morbidity and mortality in hypertensive patients with or without diabetes mellitus, and the value of these drugs in patients with heart disease and
diabetic nephropathy
. The ARBs specifically block the interaction of angiotensin II at the AT1 receptor, thereby relaxing smooth muscle, increasing salt and water excretion, reducing plasma volume, and decreasing cellular hypertrophy. These agents exert their blood pressure-lowering effect mainly by reducing peripheral vascular resistance usually without a rise in heart rate. Most of the commercially available ARBs control blood pressure for 24 h after once daily dosing. Sustained efficacy of blood pressure control, without any evidence of tachyphylaxis, has been demonstrated after long-term administration (3 years) of some of the ARBs. The efficacy of ARBs is similar to that of thiazide diuretics, beta-blockers, angiotensin-converting enzyme inhibitors or calcium channel blockers in patients with similar degree of hypertension. Higher daily doses, dietary salt restriction, and concomitant diuretic or ACE inhibitor administration amplify the antihypertensive effect of ARBs. The ARBs have a low incidence of adverse effects (headache, upper respiratory infection, back pain, muscle cramps, fatigue and dizziness), even in the elderly patients. After the approval of losartan, five other ARBs (candesartan cilexetil, eprosartan, irbesartan, telmisartan, and valsartan) and three combinations with hydrochlorothiazide (irbesartan, losartan and valsartan) have been approved as antihypertensive agents, and some 28 compounds are in various stages of development. The ARBs are non-peptide compounds with varied structures; some (candesartan, losartan, irbesartan, and valsartan) have a common tetrazolo-biphenyl structure. Except for irbesartan, all active ARBs have a carboxylic acid group. Candesartan cilexetil is a prodrug, while losartan has a metabolite (EXP3174) which is more active than the parent drug. No other metabolites of ARBs contribute significantly to the antihypertensive effect. The variation in the molecular structure of the ARBs results in differences in the binding affinity to the receptor and pharmacokinetic profiles. The differences observed in lipid solubility, absorption/distribution, plasma protein binding, bioavailability, biotransformation, plasma half-life, and systemic elimination influence the time of onset, duration of action, and efficacy of the ARBs. On the basis of the daily mg dose, the antihypertensive potency of the ARBs follows the sequence: candesartan cilexetil > telmisartan approximately = losartan > irbesartan approximately = valsartan > eprosartan. After oral administration, the ARBs are rapidly absorbed (time for peak plasma levels = 0.5-4 h) but they have a wide range of bioavailability (from a low of 13% for eprosartan to a high of 60-80% for irbesartan); food does not influence the bioavailability, except for valsartan (a reduction of 40-50%) and eprosartan (increase). A limited dose-peak plasma levels/areas under the plasma level-time curve proportionality is observed for some of the ARBs. Most of these drugs have high plasma protein binding (95-100%); irbesartan has the lowest binding among the group (90%). The steady-state volumes of distribution vary from a low of 9 L (candesartan) to a high of 500 L (telmisartan). (ABSTRACT TRUNCATE
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PMID:Clinical pharmacokinetics of angiotensin II (AT1) receptor blockers in hypertension. 1085 85
Angiotensin II receptor
antagonists (AAIIs) are the most specific inhibitors of the renin-angiotensin-aldosterone system. There are two types of angiotensin II (Ang II) receptors, the AT(1) receptor, which is responsible for all the classical physiological properties of Ang II, and the AT(2) receptor, whose function in humans remains unclear. The different AAIIs used in clinical practice vary depending on their pharmacodynamic and pharmacokinetic properties, and, for some of them, depending on their metabolism in vivo into an active metabolite. AAIIs are relatively well tolerated, and, unlike angiotensin-converting enzyme inhibitors (ACEIs), do not induce cough. AAIIs are indicated in mild, moderate and severe essential hypertension, where their efficacy has been proven in many studies. The maximal antihypertensive effect is obtained in a few days or weeks, and is somewhat retarded when compared with ACEIs. Their effect is independent of age and sex, but does depend to a certain extent on ethnic origin, since Afro-American patients are less sensitive to AAIIs than Caucasians. In general, the antihypertensive and haemodynamic response to blockers of the renin-angiotensin system is potentiated in presence of a negative salt balance and attenuated in case of a positive salt balance. This means that AAII efficiency is improved by salt depletion induced by a salt-free diet or thiazide diuretics. AAIIs induce short-term improvement of haemodynamic parameters in cardiac insufficiency. Several ongoing clinical trials have been designed to compare their efficacy in cardiac insufficiency and myocardial infarction with those of reference treatments. Valsartan has been recently shown to improve morbimortality in patients with cardiac insufficiency and receiving a conventional treatment including an ACEI. It has been convincingly shown that blockade of the renin-aldosterone system by ACEIs decreases proteinuria and slows down the progression of renal insufficiency, especially in type 2
diabetic nephropathy
. Recent trials have shown that AAIIs share the same properties as ACEIs in these indications. It appears that the beneficial effect of AAIIs and ACEIs is not entirely explained by the blood pressure lowering effect of these drugs. AAII administration increases renin release and Ang II production, which may overcome Ang II blockade. On this basis, the combination of an AAII and an ACEI has been proposed to achieve a maximal renin-angiotensin system blockade. Several experimental studies in animals and preliminary clinical studies all indicate that the combination of the two drugs may be more beneficial than either drug used alone in hypertension, cardiac insufficiency and post-myocardial infarction. Clinical trials are necessary to further document the putative advantages of such a combined therapy. The future of AAIIs depends on the following: progress made in the understanding of the molecular and cellular activities of angiotensin (angiotensin receptor signalling, receptor dimerisation, presence of other angiotensin receptor subtypes, role of AT(2) receptor, etc.);a comprehensive view of the role of the local renin system in various organs (local generation and effect of Ang II on cellular proliferation, fibrosis, inflammation, angiogenesis, etc.);predictability of the response to AAII treatment (genetic predisposition to AAII treatment, in conjunction with environmental factors); andresults of the ongoing clinical trials designed to assess the long-term effects of AAIIs in cardiovascular mortality and morbidity, in comparison with reference treatments.
...
PMID:[Angiotensin II receptor blockers: current status and future prospects]. 1203 89
Diabetes mellitus is the most common cause of end-stage renal disease in the United States, accounting for about 50% of all new cases. Although we previously established the renoprotective benefits of angiotensin converting enzyme (ACE) inhibitors in patients with coexisting hypertension and type 1 diabetes, evidence of the renoprotective effect of ACE inhibitors in patients with type 2 diabetes is less clear. We conducted the Irbesartan
Diabetic Nephropathy
Trial (IDNT) to determine whether the angiotensin II receptor blocker (ARB) irbesartan slows the progression of nephropathy in patients with type 2 diabetes independently of its blood pressure (BP)-lowering effect. In this randomized, controlled trial, we found that irbesartan was associated with a 20% reduction in the risk for the primary composite end point (doubling of the baseline serum creatinine concentration, development of end-stage renal disease, or death from any cause) compared with placebo (P =.02) and a 23% reduction compared with amlodipine therapy (P =.006). These results were not explained by differences in the BP that was achieved. In a separate study, losartan was shown to reduce the risk for progression of renal disease in patients with type 2
diabetic nephropathy
.
Angiotensin II receptor
blocker therapy has also been demonstrated to slow the progression to overt nephropathy when initiated early in the course of type 2 diabetic renal disease (ie, in patients with microalbuminuria). Based on these studies, ARBs are clearly effective in protecting against the progression of nephropathy due to type 2 diabetes. This protection is independent of their BP-lowering effect. Preclinical studies with the newest ARB, olmesartan medoxomil, suggest that this agent may provide renoprotective benefits as well.
...
PMID:The role of angiotensin II receptor blockers in preventing the progression of renal disease in patients with type 2 diabetes. 1238 93
The introduction of
Angiotensin II receptor
blockers (ARB) in 1995 was another milestone in the pharmacological management of hypertension. Due to the manifold effects on several target organs Angiotensin II is one of the most important mediator in the pathogenesis of hypertension. The blockade of the
Angiotensin II receptor
type 1 is a crucial cornerstone in interrupting the pathophysiological pathways in hypertension. Furthermore ARB have an excellent tolerability comparable with placebo. In the last decade large placebo-controlled trials could prove the efficiency of ARB in terms of morbidity and mortality. Patients after acute myocardial infarction and patients with chronic heart failure benefit from treatment with ARB equally compared to treatment with ACE inhibitors. Combining ARB and ACE inhibitors in patient after myocardial infarction increases the rate of adverse events without improving survival. Increase of microalbuminuria and worsening of
diabetic nephropathy
is reduced by ARB in patients with diabetes type 2, but an advantage over ACE inhibitors could not be documented. Hypertensive patients with electrocardiographically left ventricular hypertrophy treated with ARB seem to have an additional benefit in terms of morbidity and mortality compared to treatment with beta-blockers. In the early treatment of stroke patients treated with ARB have a lower 12-mounth mortality than patients receiving placebo. In conclusion,
Angiotensin II receptor
blockers are due to their well proved efficiency, the cardio- and renoprotective qualities and the excellent tolerability profile a useful therapeutic option in the management of patients with hypertension.
...
PMID:[Angiotensin II receptor blockers--evidence along the cardiovascular continuum]. 1588 24
Angiotensin II receptor
antagonists (angiotensin receptor blockers; ARBs) and thiazide diuretics have an accepted place in the management of hypertension. Most patients require combination therapy with two or more drugs to adequately control blood pressure to targets recommended by European and international guidelines. ARBs and the thiazide diuretic hydrochlorothiazide have complementary modes of action. Fixed-dose combinations of an ARB and low-dose hydrochlorothiazide provide a convenient and effective treatment option for patients who do not achieve blood pressure targets on monotherapy, without compromising the placebo-like tolerability of ARBs. In Europe, fixed-dose combinations with hydrochlorothiazide currently are available for the ARBs candesartan, eprosartan, irbesartan, losartan, telmisartan, and valsartan. Recently, a number of studies have focused on the use of ARBs in monotherapy and in combination therapy, in conditions including congestive heart failure, post-myocardial infarction management, hypertension with cardiovascular risk factors, and diabetic and non-
diabetic nephropathy
. Evidence from these studies suggests a beneficial role beyond the antihypertensive effect of these therapies in providing protection against cardiovascular, renovascular, and cerebrovascular events.
...
PMID:Angiotensin II receptor antagonists alone and combined with hydrochlorothiazide: potential benefits beyond the antihypertensive effect. 1590 Dec 5
The renin-angiotensin-aldosterone system plays a key role in the regulation of fluid and electrolyte balance.
Angiotensin II receptor
blockers (ARBs) inhibit angiotensin II type 1 receptors and large clinical trials have shown that they are effective in many cardiovascular diseases including hypertension, heart failure, myocardial infarction and
diabetic nephropathy
. They lower blood pressure effectively, are very well tolerated and can be used as monotherapy or in combination with other drug classes for the treatment of hypertension. ARBs are particularly suitable for hypertensive patients with co-morbidities such as diabetes, microalbuminuria, proteinuria, left ventricular hypertrophy and heart failure. Unlike angiotensin-converting enzyme inhibitors, ARBs do not cause persistent dry cough. For patients in whom angiotensin-converting enzyme inhibitors are indicated but not tolerated, an ARB should be considered. Periodic monitoring of renal function and electrolytes is required in patients treated with an ARB.
...
PMID:Therapeutic potential of angiotensin receptor blockers in hypertension. 1673 15
Angiotensin II receptor
antagonists (angiotensin II receptor blockers; ARBs) are a class of antihypertensive drugs that are generally considered comparable to ACE inhibitors in the prevention of heart and kidney failure. However, these two classes of agents do interfere in different stages of the renin-angiotensin system. In patients with type 2 diabetes mellitus, advantages for ARBs over conventional (non-ACE inhibitor) therapy on progression from micro- to macroalbuminuria and overt nephropathy and end-stage renal disease have been shown in clinical trials. In patients with type 2 diabetes and end-stage renal disease, the need for dialysis and/or transplantation results in the use of major healthcare resources. This paper reviews the available economic evidence on treatment with ARBs in type 2 diabetic patients with advanced renal disease.Within-trial analytic and Markov model economic evaluations of the RENAAL (Reduction of Endpoint in Non-insulin dependent diabetes mellitus with Angiotensin II Antagonist Losartan), IDNT (Irbesartan
Diabetic Nephropathy
Trial) and IRMA (IRbesartan in type 2 diabetes with MicroAlbuminuria)-2 studies suggest that treatment with ARBs in patients with type 2 diabetes with overt or incipient nephropathy confers health gains and net cost savings compared with conventional (non-ACE inhibitor) therapy. For reimbursement and reference pricing decisions, there is a need for a head-to-head comparison of an ACE inhibitor with ARBs to model all possible costs and effects of ACE inhibitors and ARBs. This will result in a proper pharmacoeconomic outcome, where both types of drugs can be compared for healthcare decisions.
...
PMID:Pharmacoeconomics of angiotensin II antagonists in type 2 diabetic patients with nephropathy: implications for decision making. 1676 1
Angiotensin II receptor
blockers (ARBs) are widely used in patients with hypertension, heart failure,
diabetic nephropathy
, and other conditions. Over-stimulation of AT2 receptor as a result of AT1 blockade may contribute to the beneficial effects of ARBs through vasodilation and inhibition of cardiac and vascular hypertrophy and fibrosis. Some experimental studies, however, suggested that AT, receptor overstimulation, in addition to beneficial effects, might trigger inhibition of angiogenesis and apoptosis. In a review, some authors suggested that ARBs may increase the risk of myocardial infarction. This position triggered a hot scientific debate and further analyses of existing data. We completed a meta-analysis of randomized clinical trials comparing ARBs with either placebo or active drugs different from ARBs. ARBs were not associated with an excess risk of myocardial infarction (odds ratio 1.03 in a random-effect model and 1.02 in a fixed-effect model). Cardiovascular mortality did not differ between ARBs and drugs different from ARBs (odds ratio 1.00 in a random-effect model and 0.99 in a fixed-effect model) and it was slightly lesser with ARBs than with placebo (odds ratio 0.91; 95% confidence interval 0.83-0.99; p = 0.042) in a prespecified subgroup analysis. Other meta-analyses confirmed these data. In conclusion, evidence from randomized trials does not support the hypothesis that AT2 receptor over-stimulation produces harmful clinical effects. Current indications and contraindications to the use of ARBs in patients with hypertension, heart failure, and
diabetic nephropathy
should be maintained and probably extended to the entire class of these drugs.
...
PMID:[Antihypertensive therapy and cardiovascular prevention. The role of angiotensin II receptor blockers]. 1769
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