Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0730345 (microalbuminuria)
 4,018 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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

Patients with hypertension do not comprise a homogeneous group, and the majority present with a variety of concomitant and associated conditions. Antihypertensive therapies should therefore be effective and well tolerated in a wide range of patients and should, ideally, ameliorate the negative target-organ effects of hypertension, such as atherosclerosis, cardiovascular remodelling and renal impairment. Evidence is accumulating that the new angiotensin II type 1 receptor blocker, candesartan cilexetil, lowers blood pressure effectively and is well tolerated in a variety of patient groups, including women and the elderly. In patients with severe hypertension, a treatment schedule based on candesartan cilexetil, with the addition of diuretic and calcium antagonist therapy as needed, has been found to control blood pressure successfully. Candesartan cilexetil does not affect glucose tolerance or lipid profiles in patients with diabetes mellitus, and it is not associated with any of the side effects of other antihypertensive agents that would make it unsuitable for use in patients with pulmonary disease. Initial clinical studies have indicated that candesartan cilexetil is well tolerated and effective in patients with heart failure. Furthermore, the available evidence shows that treatment with candesartan cilexetil can reverse the negative effects of hypertension on left ventricular hypertrophy and microalbuminuria. It therefore appears that the pronounced efficacy and placebo-like tolerability of candesartan cilexetil, as demonstrated in large clinical trials of patients with mild to moderate hypertension, can be extended to a wide range of specific patient groups.
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PMID:Efficacy and tolerability of candesartan cilexetil in special patient groups. 1105 33

1. Combined treatment of spontaneously hypertensive rats (SHR) with AT1 receptor antagonists and angiotensin-converting enzyme (ACE) inhibitors has been shown to reduce mean arterial pressure (MAP) more than monotherapy with either agent. The aims of the present study were to investigate the effects of chronic dual renin-angiotensin system (RAS) inhibition using non-hypotensive doses of the AT1 receptor antagonist candesartan cilexetil and the ACE inhibitor perindopril on cardiovascular function and structure. 2. Adult male SHR, aged 15 weeks, were divided into four groups: (i) candesartan cilexetil (0.5 mg/kg per day in drinking water); (ii) perindopril (0.3 mg/kg per day in drinking water); (iii) combined treatment (dual RAS inhibition); or (iv) the appropriate vehicle (0.1% ethanol/0.1% polyethylene glycol/1.5 mmol/l sodium bicarbonate dissolved in water for candesartan cilexetil; distilled water for perindopril). Systolic blood pressure was measured weekly using the tail-cuff method and urinary microalbuminuria was measured fortnightly. 3. After 4 weeks, rats were instrumented for intravenous drug administration and measurement of MAP. At this time, the cardiovascular effects of angiotensin (Ang) I and AngII (5-20 ng) and sodium nitroprusside (SNP) and acetylcholine (ACh; 1-5 micro g) were assessed. In addition, left ventricular : bodyweight and media : lumen ratios were determined as indices of cardiac and vascular hypertrophy, respectively. 4. Candesartan cilexetil and perindopril alone had minimal effect on MAP when measured both directly and indirectly, whereas direct MAP was significantly decreased in the combined treatment group (131 +/- 6 mmHg; P < 0.05) compared with the vehicle group (156 +/- 9 mmHg). Pressor responses to AngI were significantly decreased in all groups compared with the vehicle-treated group and pressor responses to AngII were significantly decreased in the candesartan cilexetil-treated (P < 0.01) and combined treatment groups (P < 0.01) compared with the vehicle-treated group. Depressor responses to ACh and SNP were not significantly affected by any of the antihypertensive therapies compared with vehicle-treated SHR. 5. Vascular hypertrophy was significantly decreased in the candesartan cilexetil and combined groups compared with the vehicle-treated group, whereas cardiac hypertrophy was reduced, with the rank order of effect being: dual RAS inhibition > perindopril > candesartan cilexetil. Urinary albumin tended to decrease with dual RAS inhibition, but was not significantly affected by this short-term treatment. 6. These results demonstrate the efficacy of low-dose dual RAS inhibition as an antihypertensive modality, at least in SHR, not only in reducing arterial pressure, but also in improving cardiovascular structure.
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PMID:Cardiovascular status following combined angiotensin-converting enzyme and AT1 receptor inhibition in conscious spontaneously hypertensive rats. 1285 20

Patients with hypertension do not comprise a homogeneous group, and the majority present with a variety of concomitant and associated conditions. Antihypertensive therapies should therefore be effective and well tolerated in a wide range of patients and should, ideally, ameliorate the negative target-organ effects of hypertension, such as atherosclerosis, cardiovascular remodelling and renal impairment. Evidence is accumulating that the new angiotensin II type 1 receptor blocker, candesartan cilexetil, lowers blood pressure effectively and is well tolerated in a variety of patient groups, including women and the elderly. In patients with severe hypertension, a treatment schedule based on candesartan cilexetil, with the addition of diuretic and calcium antagonist therapy as needed, has been found to control blood pressure successfully. Candesartan cilexetil does not affect glucose tolerance or lipid profiles in patients with diabetes mellitus, and it is not associated with any of the side effects of other antihypertensive agents that would make it unsuitable for use in patients with pulmonary disease. Initial clinical studies have indicated that candesartan cilexetil is well tolerated and effective in patients with heart failure. Furthermore, the available evidence shows that treatment with candesartan cilexetil can reverse the negative effects of hypertension on left ventricular hypertrophy and microalbuminuria. It therefore appears that the pronounced efficacy and placebo-like tolerability of candesartan cilexetil, as demonstrated in large clinical trials of patients with mild to moderate hypertension, can be extended to a wide range of specific patient groups.
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PMID:Efficacy and Tolerability of Candesartan Cilexetil in Special Patient Groups. 2842 1