Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.23.15 (renin)
 35,795 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 26-year-old female with Bartter's syndrome associated with Graves' disease is reported. This patient had a history of Graves' disease from the age of 22 and anti-thyroid drug (Methimazole) had been administered for 2 years. Thyroid function returned to normal but general fatigue and polyuria continued. Hypokalemia was diagnosed at 25 years of age and she was referred to our hospital for evaluation. Blood pressure was normal and laboratory data revealed normal thyroid function, hypokalemic alkalosis, high plasma renin activity and high plasma aldosterone concentration. She showed normal pressor sensitivity to norepinephrine infusion, grossly diminished pressor sensitivity to exogenous angiotensin II infusion compared with the normal. A renal biopsy specimen showed juxtaglomerular cell hyperplasia. Electron microscopy confirmed lacis cell (agranular cell) proliferation.
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PMID:Bartter's syndrome--case report. 15 51

A four-year-old girl with hypertension (140/60) and chronic hypokalemic alkalosis was studied to determine the origin of this clinical feature. High exchangeable sodium (56.7 meq/kg vs. 45-55 meq/kg in controls) was associated with a low plasma renin activity (6 ng/1/min vs. 26 +/- 3.1 in controls) and reduced aldosterone secretion rate (5.56 mug/day; normal: 50-150 mug per day)). A low corticosterone secretion rate (0.228 mg/day vs. 0.50-0.65 in controls) and urinary tetrahydrodeoxycorticosterone (0.007 mg/day vs. 0.03-0.09 mg/day in controls) were found. The basal secretion rate of cortisol was also low (1.80 mg/m2/day vs. 5.4-16.7 mg/m2/day in controls) in spite of normal plasma ACTH: 78 pg/ml. The normal increase of the cortisol secretion rate (from 1.80 to 65 mg/m2/day) after synthetic ACTH stimulation ruled out a 17 alpha hydroxylase deficiency. The low sweat Na/K ratio (0.25) and the good suppressing efficacy of dexamethasone and of the spironolactones on hypertension and on the hypokalemic alkalosis agreed with the hypersecretion of a mineralocorticoid. The secretion rate of 18 hydroxydeoxycorticosterone was high (91 mug/day/1.73 m2 vs. 40-80 mug per day and per 1.73 m2). As the mineralocorticoid potency of this steroid is weak, we speculate that it might be the precursor of a more potent but unknown mineralocorticoid which could influence the ACTH secretion.
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PMID:Unusual low plasma renin hypertension in a child. 18 94

Evidence for the existence of a hormone that is stimulable by adrenocorticotropic hormone (ACTH) and capable of causing hypertension has been collected in several patients. This hormone is not a known mineralocorticoid or glucocorticoid. The hypothesis that a steroid can produce hypertension was tested in an 18-year-old man with dexamethasone-suppressible hypertension. During dexamethasone treatment, when aldosterone secretion was suppressed, less than normal and the patient was normotensive, steroids were given by constant infusion in an attempt to reproduce the hypertension of the dexamethasone-free state. Hypertension was not caused by 5 days of administration of aldosterone, 18-hydroxydeoxycorticosterone (18-OH-DOC) at 1 mg/day, or deoxycorticosterone (DOC) at 30 mg/day. However, sodium retention and potassium loss were observed during infusion of aldosterone and DOC. Hypertension was produced within 5 days during infusion of ACTH or oral metyrapone. The hypertensive effect of the metyrapone was eliminated by the additional treatment with aminoglutethimide. These studies suggest that an ACTH-dependent steroid rather than aldosterone, 18-OH-DOC, or DOC may be the cause of the hypertension in this patient. Study of a 3-year-old child who presented with short stature, hypertension, hypokalemic alkalosis, suppressed renin and ACTH, and decreased excretion of all known steroids suggested excessive secretion of a pressor hormone. Reversal of the hypertension and hypokalemic alkalosis occurred when spironolactone was administered. ACTH exacerbated the clinical and biochemical abnormalities, suggesting that the secretion of the unknown factor was dependent on ACTH. A study of the urinary steroids revealed remarkably low excretion of aldosterone and cortisol. Plasma levels of ACTH were low. The low production of aldosterone was not associated with the increased excretion of precursor metabolites. These finding suggest the secretion of an unknown hypertensive factor of remarkably high potency, with the ability to suppress the secretion of both renin and ACTH.
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PMID:Mineralocorticoid hypertension in childhood. 32 86

In summary, the cardinal features of the syndrome of renal juxtaglomerular hyperplasia include overproduction of plasma renin activity, elevation of plasma angiotensin II concentration, elevation of aldosterone secretion and of plasma aldosterone concentration, hypokalemic alkalosis, and a resistance of arterioles to the pressor action of angiotensin II and norepinephrine. In the present studies, elevation of urinary PGE2 but not of PGF2alpha has been demonstrated. Inhibition of prostaglandin synthetase with indomethacin or ibuprofen has been shown to decrease plasma renin activity, and plasma aldosterone concentration and secretion rate, leading to a positive potassium balance and restoration of normal plasma potassium. The inhibitors decreased and glomerular filtration rate, and induced sodium retention. The results indicate that overproduction of PGE by the kidneys is a cardinal feature, but not necessary the primary one, in the pathogenesis of this syndrome.
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PMID:Prostaglandins are overproduced by the kidneys and mediate hyperreninemia in Bartter's syndrome. 82 45

Studies in a juvenile hypertensive syndrome associated with suppressed plasma renin activity and hypokalemic alkalosis failed to reveal overproduction of aldosterone or any other known steroid. There was however an abnormal increase in the fraction of unconjugated urinary steroids. Analysis of this fraction following the administration of labeled cortisol revealed that it was largely composed of dihydro metabolites reduced either at 4,5 or at C-20 and that the 4,5-dihydro fraction contained an abnormal increase in 5alpha- relative to 5beta-metabolites. There was, however, no absolute defect in the complete reduction of ring A to form tetrahydro derivatives. These findings, together with observations by Marver and Edelman that 5alpha-dihydrocortisol may be an effective mineralcorticoid, suggest the possibility of an etiologic relationship between the metabolic abnormality and the patient's hypertensive disorder.
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PMID:An abnormality in steroid reductive metabolism in a hypertensive syndrome. 84 92

A unique syndrome in a three-year-old American Indian girl was characterized by signs and symptoms of mineralocorticoid excess in the absence of excessive secretion of any known sodium-retaining steroids. Hypertension and hypokalemic alkalosis were corrected by spironolactone or a low sodium diet. Plasma renin activity was suppressed but the secretion of aldosterone was undetectable and was not stimulated by salt depletion. There was no evidence of abnormal accumulation of aldosterone precursors and metabolism of a tracer dose of the hormone was normal. Secretion rates of cortisol, corticosterone, deoxycorticosterone, deoxycortisol and aldosterone were very low and did not increase normally with ACTH administration. However ACTH administration aggravated hypertension and hypokalemia. Dexamethasone did not improve hypertension. Despite low secretion of glucocorticoids and mineralocorticoids, the patient showed no addisonian features and survived severe illness. Secretion of a factor of adrenocortical origin was suggested by the exacerbation of the syndrome of ACTH. The unidentified factor appears to be both a potent glucocorticoid and mineralocorticoid.
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PMID:Evidence for an unidentified steroid in a child with apparent mineralocorticoid hypertension. 87 May 17

In three patients with Bartter's syndrome, indomethacin administration resulted in the disappearance of the hypokalemic alkalosis and in a normalization of the elevated plasma renin activity. Changes in calcium and phosphate metabolism during indomethacin medication seemed to indicate an increase in reabsorption activity of the renal proximal tubulus. A kidney biopsy performed in one of the patients showed, besides hyperplasia of juxtaglomerular cells, hyperplasia of interstitial medullary cells which are presumed to produce prostaglandins. As indomethacin is a well-known inhibitor of prostaglandin synthesis, the observations suggest that an overproduction of renal prostaglandins could well be of pathogenetic significance in Bartter's syndrome.
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PMID:Indomethacin in Bartter's syndrome: does the syndrome represent a state of hyperprostaglandinism? 91 67

Urinary excretion of kallikrein has been studied in a patient with hypokalemic alkalosis, hyperplasia of the renal juxtaglomerular apparatus and hyperreninemia, secondary aldosteronism and resistance to the pressor effect of angiotensin II (Bartter's syndrome). Urinary kallikrein was found exceedingly high in several determination, whereas it was low in patients with essential hypertension and high in patients with primary aldosteronism. Urinary kallikrein decreased after spironolactone therapy. The rise of kallikrein excretion (which is not related to plasma renin) in this case is probably caused by a direct action of the chronic excess of plasma aldosterone; it could not be accounted for as secondary to natriuresis.
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PMID:Urinary kallikrein excretion in Bartter's syndrome. 99 21

Discussed here is a patient with normotension, hypokalemic alkalosis, hyperreninemia, hyperaldosteronism, juxtaglomerular cell hyperplasia and insensitivity to the pressor effects of angiotensin (Bartter's syndrome). The hyperreninemia and hyperaldosteronism were both suppressible with volume expansion. Hypokalemia was correctible both short-term with potassium chloride infusions and long-term with spironolactone. Nevertheless, the abnormal pressor response to infused angiotensin could not be corrected by these maeuvers, suggesting that this defect is likely to be of primary pathophysiologic significance. We found that potassium loading markedly stimulated aldosterone excretion. This may explain the inadequacy of potassium supplementation alone to correct the hypokalemia and the observed "escape" from the potassium conserving effects of spironolactone seen in patients with Bartter's syndrome. The administration of propranolol in large doses only partially suppressed the marked hyperreniemia of our patient and failed to prevent a subsequent rise in the renin level which was associated with spironolactone therapy. In contrast, suppression of the renin level to normal was demonstrated by sodium loading. It is suggested that patients with Bartter's syndrome be treated simultaneously with large doses of spironolactone and a high sodium intake.
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PMID:Bartter's syndrome. New insights into pathogenesis and treatment. 116 59

A case of primary aldosteronism treated with spironolactone therapy has been followed up for 24 years. This is probably the longest case of spironolactone therapy for primary aldosteronism that has ever been reported. Long-term treatment with spironolactone controlled the hypertension and prevented hypokalemic alkalosis in this patient, without any deleterious effects on steroid biosynthesis. Based on data obtained during dose reduction and subsequent withdrawal of spironolactone, it is suggested that the suppressed plasma renin activity associated with adenoma-induced aldosteronism develops prior to hypokalemia and hypertension.
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PMID:Twenty-four year spironolactone therapy in an aged patient with aldosterone-producing adenoma. 131 94


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