Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Three case histories are described which highlight some of the predisposing risk factors and therapeutic strategies in the event of acute severe renal failure during treatment with ACEI. With appropriate therapy, renal function is usually restored within a few days. Renal artery stenosis, dehydration and diuretics stimulate the renin angiotensin system and make preservation of normal renal function, increasingly dependent on angiotensin II. The prevalence of renal artery stenosis is substantially increased in patients with peripheral vascular disease or with coronary artery disease with concomitant hypertension. Patients should be told about the increased risk of adverse effects to the kidneys if they become dehydrated. In these cases it is essential to reduce the dose diuretics and ACEI, and it may be necessary to give parenteral fluid substitution.
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PMID:[Severe renal failure during treatment with angiotensin-converting enzyme inhibitors]. 157 48

Measures to prevent ischemic stroke after aneurysmal subarachnoid hemorrhage include management of fluids to avoid dehydration, use of calcium entry blocking drugs, and when necessary, therapy with drug-induced hypertension and hypervolemic hemodilution. Promising treatments that may also prove to be effective include 21-aminosteroids, intrathecal thrombolytic therapy, and transluminal angioplasty.
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PMID:Prevention of brain ischemia after aneurysmal subarachnoid hemorrhage. 155 6

The authors analysed the dynamics of the activity of the renin-angiotensin-aldosterone, hypophyseal-adrenal, and sympathoadrenal systems in 46 patients during a hemodialysis session according to the type of hemodynamics. No essential changes were encountered in the hormone concentration in patients with normotension and "controllable" hypertension. In patients with "uncontrollable" hypertension the dialysis dehydration was attended by increased activity of the renin-angiotensin-aldosterone system, the level of cortisol and the adrenocorticotropic hormone increased slightly. Daily catecholamine excretion was 2-3.5 times below the lowest normal value. Noradrenaline clearance of the plasma membrane dialyser was 82.1 ml/min. Increase in the concentration of noradrenaline, and the activity of renin and aldosterone were encountered both in hypotension and in arterial hypertension. It is concluded that disturbed water balance, dyselectrolythemia, anemia, infectious complications, etc. are the trigger factor of decompensation of the system of the hormonal hemodynamic regulation. Substitution adrenomimetic therapy for arresting collaptoid reactions is inexpedient. Systematic use of medicinal agents should be avoided in favour of a search for an optimal dialysis regimen, should this prove ineffective the decision should be made in favour of an operation.
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PMID:[The activities of the renin-angiotensin-aldosterone and sympathetic-adrenal systems during hemodialysis]. 165 15

Patients with apparent polycythaemia are characterised by a raised packed cell volume (PCV; males above 0.51, females above 0.48) but normal red cell mass (RCM; less than 25% greater than predicted). Prediction and interpretation of RCM and PV should be based on height and weight, since the use of body weight alone is misleading. Patients with PCV values up to 0.60 may have apparent polycythaemia but only 18% have a reduced PV (relative polycythaemia). Therefore, the most common cause of the raised PCV is a change in RCM and/or PV within their normal ranges. The clinical associations and possible causes for the RCM/PV changes include male sex, obesity, dehydration, diuretics, smoking, hypertension, alcohol, arterial oxygen desaturation, renal disease and increased catecholamine levels. Retrospective studies of patients with apparent polycythaemia and information from other groups of polycythaemic patients suggest an increased risk of vascular occlusion, although other factors, such as hypertension and smoking, are also involved. Proposed management includes modification of possible underlying causes and examination for risk factors for vascular occlusion. In patients with PCV levels chronically above 0.54 venesection should be used, but patients with PCV values below this level should only be venesected if they are considered to be at risk of vascular occlusion. The suggested target value for PCV for venesected patients is 0.45 or below.
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PMID:Apparent polycythaemia. 178 79

We report a case of severe hypertension in the newborn period due to obstruction of the right renal artery. The baby presented with polyuria leading to dehydration and was found to have hyponatraemia and severe renal salt loss. When sudden malignant hypertension is induced in experimental conditions, a high pressure diuresis and increased angiotensin II production are found. These findings could explain the renal salt loss, notwithstanding the effects of secondary hyperaldosteronism and hyper-reninaemia.
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PMID:Renovascular hypertension: a rare cause of neonatal salt loss. 186 85

1. Serum angiotensin converting enzyme activity (ACEA) and plasma renin activity (PRA) were determined in rats under different experimental conditions such as: nephrotic syndrome (NS), bilateral nephrectomy (BN), renovascular hypertension (RH), dehydration (DEH), anaesthesia (AN), low sodium diet (LSD) and high sodium diet (HSD), and injection with propranolol (PRO) and isoprenaline (ISO). 2. PRA increased in LSD, AN, NS, RH, DEH and IPT groups, and decreased in HSD, BN, and PRO groups. Serum ACEA did not change in RH, HSD, IPT, DEH, AN, and PRO groups, increased in NS group, and decreased in LSD and BN groups. 3. Serum ACEA changed in the opposite direction to PRA only in the LSD group. This finding suggests that ACE may limit the full expression of the renin-angiotensin system in the LSD group, but not in the other groups.
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PMID:Serum angiotensin converting enzyme activity and plasma renin activity in experimental models of rats. 216 78

Since hypertension may compromise the ability to withstand hypernatremic dehydration, we investigated the impact of two experimental models of hypertension and pharmacologic normalization of blood pressure on the tolerance to chronic hypernatremic dehydration. In DOCA-salt hypertensive animals and the spontaneously-hypertensive rat (SHR), there was increased mortality and cerebral cell shrinkage during hypernatremic dehydration, compared to control Sprague-Dawley or Wistar-Kyoto rats. These findings were paralleled by significant differences in the brain intracellular water compartment size (ml/100 g dry weight), i.e. 233 +/- 6, Sprague-Dawley vs 189 +/- 8, DOCA-salt, P less than 0.01; 246 +/- 3, Wistar-Kyoto vs 194 +/- 6, SHR, P less than 0.01. Normalization of the blood pressure in the SHR with captopril restored 48% of the cerebral cell volume regulatory capacity observed in normotensive Wistar-Kyoto rats. We conclude that sustained hypertension increases the risk of hypernatremic dehydration in select circumstances. Correction of the elevated blood pressure promotes partial recovery of normal cerebral cell volume regulation.
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PMID:The effect of hypertension and its treatment on cerebral cell volume regulation during hypernatremic dehydration. 218 50

The propensity to prefer and to consume salty foods varies considerably from person to person, and excessive salt intake has been linked to a number of pathological conditions. Extracellular dehydration occurs in humans after vomiting or diarrhea and is commonly observed during pregnancy. Because the hormonal responses to extracellular dehydration are known to increase salt appetite, we tested the hypothesis that extracellular dehydration during pregnancy increases the propensity of offspring to consume salt. Pregnant rats were treated with polyethylene glycol, which is known to produce extracellular dehydration and to exaggerate sodium appetite. The offspring of these treated pregnant rats showed an increase in salt appetite as compared with the offspring of control untreated dams. These results demonstrate that extracellular dehydration during pregnancy can enhance the natriophilic propensity in offspring and suggest that gravidic vomiting may contribute to the epidemiological factors of hypertension and other pathologies.
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PMID:Extracellular dehydration during pregnancy increases salt appetite of offspring. 230 41

The acute, 60 min blood pressure and plasma renin responses to an oral test dose of captopril given to a quietly seated patient can be used to gain information quickly on renin dependency or lack of it in a hypertensive situation. This information is verified by a baseline renin sodium profile test. These two diagnostic steps define either renin dependency or a sodium-volume mechanism involved in the vasoconstrictor. At the same time they also enable the complete diagnosis or exclusion of curable renovascular disease. For long-term therapy, pharmacologic inhibition of the renin-angiotensin system can be accomplished by or using converting enzyme inhibitors to block angiotensin II formation or beta receptor blocking drugs to block renin secretion and by combining the two. Inhibition of the renin-angiotensin system is the logical first step in antihypertensive drug therapy, both for acute hypertensive emergencies or chronic therapy, whenever the hypertension is largely or significantly renin dependent, i.e., in the high and normal renin forms of hypertension. This includes up to 70% of patients with essential hypertension. If converting enzyme inhibition or beta blockade is only partially effective, the two can be combined to achieve more complete blockade. A more popular alternative to this has been the addition of a diuretic as the second drug. However, this introduces well-known problems of diuretic therapy including dehydration, which eliminates the conceptual advantage of pure blockade of renin-mediated vasoconstriction, i.e., reducing pressure without reducing tissue flow.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:When is it useful to inhibit the renin-angiotensin system for treating hypertension? 241 20

The author presents data obtained by the study of a group of 729 patients aged between 60 and 90 years with regard to cardiopathies. The most frequently encountered diseases were arterial hypertension (35.6%) and atherosclerotic heart disease (49.7%). There were small differences in the number of patients by sex. The more severe aspects were those determined by hypertensive cardiopathy and myocardial infarctions (acute, in antecedents, iterative). Congestive heart disease with failure of the myocardium is frequently associated with atrial fibrillation. Some particularities related to pharmacokinetics (such as reduction of intestinal absorption, slow elimination of drugs, the reduction in the number of active nephrons) make mandatory a different kind of medical treatment, with lower doses of drugs as compared to adults. Particular attention should be given to the risk of dehydration in the aged, to complication determined by digitalic preparation and anticoagulants, to associated affections and to complications of the cardiopathies. A diet with low amounts of sodium, predominantly alkaline, careful hygiene of the patients, correct administration of the drugs, and health education should be permanently considered by the ancillary personnel caring for such patients.
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PMID:[Cardiopathies in the elderly. The diagnostic and treatment problems]. 251 35


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