Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020438 (hypercalciuria)
 2,502 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The immature kidney may be adversely affected by a variety of vasoactive or diuretic drugs, either administered to the mother during pregnancy, or to the neonate. Inhibitors of the angiotensin-converting enzyme administered to the hypertensive pregnant woman can severely and sometimes definitely impair renal function in the fetus, leading to postnatal anuria. Pathogenesis involves interference with the renin-angiotensin system and the prostaglandins. Beta-adrenergic agents administered during labor depress glomerular filtration rate transiently. Tolazoline, an alpha-adrenergic blocking agent useful in the treatment of persistent pulmonary hypertension of the neonate induces intense renal vasoconstriction with consequent hypoperfusion. Indomethacin, a prostaglandin synthetase inhibitor used for the pharmacological closure of a patent ductus arteriosus, also increases renal vascular resistance, and decreases urine output. Furosemide, the drug most often used in oliguric neonates, may also adversely affect the newborn infant. Its use has been associated with an increase in the incidence of patent ductus arteriosus, hypercalciuria, nephrocalcinosis and secondary hyperparathyroidism. These observations demonstrate that the proper use of drugs requires that the therapeutic endpoint be clearly defined and the predictable side effects be anticipated.
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PMID:Adverse effects of drugs on the immature kidney. 290 Dec 76

This study was performed to assess whether treatment with prostaglandin synthesis inhibitors decreases calcium excretion in patients with idiopathic hypercalciuria. Nineteen hypercalciuric (12 with fasting hypercalciuria (FH), 7 with nonfasting hypercalciuria (NFH) and 8 control non-hypercalciuric stone formers were treated with sodium diclofenac, 50 mg t.i.d. for 2 weeks. After a washout phase, 7 FH patients received 200 mg/day of sulindac (a nonsteroidal antiinflammatory agent (NSAID) inactive on renal prostaglandin synthetase) for 14 more days. Diclofenac reduced urine calcium excretion in subjects with idiopathic hypercalciuria with either normal or elevated fasting urinary calcium (from 387 +/- 26 to 240 +/- 23 mg/day, P less than 0.001; and from 370 +/- 39 to 246 +/- 40 mg/day, P less than 0.05, respectively), whereas it was ineffective in normocalciuric stone formers. Similar antihypercalciuric effectiveness was exerted by sulindac in the seven FH patients. The antihypercalciuric action exerted by diclofenac in subjects with FH was associated with a significant increment in serum PTH (48 +/- 4 vs, 70 +/- 9 pmol/liter, P less than 0.05), whereas in NFH subjects, the antihypercalciuric effect of diclofenac on NFH was not associated with a change in parathyroid activity. Since the major effect of NSAIDs is to decrease prostaglandin synthesis, these data suggest that prostaglandins may play a pathogenetic role in idiopathic hypercalciuria. Furthermore, they suggest that PTH is suppressed in patients with FH, possibly due to stimulation of prostaglandin-mediated bone resorption process.
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PMID:Evidence for a prostaglandin-mediated bone resorptive mechanism in subjects with fasting hypercalciuria. 314 68

Growth from birth to the age of 19 years was studied in a patient with the neonatal form of Bartter syndrome. The initial modes of therapy (extra fluid, potassium supplements and triamterene) resulted in satisfactory but not optimal growth. Treatment with spironolactone together with potassium led to impressive catch-up growth. When the patient reached the age of 9 years, indomethacin therapy was started, which resulted in a second growth acceleration and was also accompanied by a significant reduction of both polyuria and hypercalciuria. Puberty developed normally, menarche occurred at 12 years 4 months and a normal adult height of 162 cm was reached at the age of 14 years. Treatment with prostaglandin synthetase inhibitors seems to be the best therapy for children with the neonatal form of Bartter syndrome.
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PMID:Growth from birth to adulthood in a patient with the neonatal form of Bartter syndrome. 315 13

The treatment of idiopathic hypercalciuric stone formers with the prostaglandin synthetase inhibitors flurbiprofen and indomethacin has been studied in two phases. Ten patients were studied in a metabolic unit for 14 days that included a control period of 7 days on a controlled intake of dietary calcium, followed by treatment with flurbiprofen 50 mg tds. Three patients were studied along similar lines and were treated with indomethacin 25 mg tds. A significant reduction in urinary calcium excretion was noted during the 7-day control period during which dietary calcium intake was reduced to 700 mg daily. No further significant reduction in urinary calcium excretion was observed during the treatment with either flurbiprofen or indomethacin. Thirteen patients then continued to take flurbiprofen 50 mg tds for between 1 and 12 months. A small but not statistically significant reduction in urinary calcium excretion was noted by the third month of treatment, but this was not sustained. This study confirms the benefit of dietary restriction of calcium as the primary approach to the treatment of idiopathic hypercalciuria. Neither flurbiprofen nor indomethacin reduced urinary calcium excretion to significant levels. Their routine use for the treatment of idiopathic hypercalciuria cannot be recommended from the evidence of this study.
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PMID:Prostaglandin synthetase inhibitors and their effect on urinary calcium excretion and other parameters in idiopathic hypercalciuria. 642 55

Hypercalciuria is well recognized as an important factor in the cause of idiopathic calcium stone disease. Identification of the exact mechanism for the renal tubular handling of calcium has proved elusive, hence, treatment methods to alter the concentration of urine calcium in hypercalciuric stone formers have hitherto been non-specific. It is now well established that renal prostaglandins influence intrarenal hemodynamics and tubular electrolyte excretion. As the renal handling of sodium and calcium is intimately related, the possibility that the mechanism underlying hypercalciuria may be prostaglandin mediated was considered. Experiments were performed in conscious Sprague-Dawley rats (n = 10) to determine the changes in calcium excretion following prostaglandin synthetase inhibition with indomethacin. Calcium excretion was significantly reduced (p less than 0.01), compared with control animals (n = 10). Further experiments were performed in anesthetized monkeys (Macaca fascicularis) to see if the inhibitory effect of indomethacin was reversible. Exogenous prostaglandin (PGE2) infusion resulted in a marked calciuretic response without producing changes in glomerular filtration rate or blood pressure. Forty-three hypercalciuric patients were treated with a prostaglandin inhibitor for periods ranging from 2 to 4 weeks, and all showed a significant fall in urinary calcium excretion to within the normal range. This clinical and experimental study suggests that prostaglandin (PGE2) is a hormone which determines the renal handling of calcium by influencing renal tubular function.
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PMID:The influence of renal prostaglandins on urinary calcium excretion in idiopathic urolithiasis. 657 32

In a clinical study of 275 idiopathic stone formers the GFR was significantly raised in hypercalciuric patients compared with normal controls P less than 0.001). The possibility that the mechanism underlying hypercalciuria and raised GFR may be prostaglandin-mediated was considered because it is now well established that prostaglandins regulate intra-renal haemodynamics and influence tubular electrolyte excretion. Experiments were performed in conscious Sprague Dawley rats to determine the changes in calcium and sodium excretion following prostaglandin synthetase inhibition with indomethacin. Both calcium and sodium excretion together with urine flow were significantly reduced (P less than 0.002). Further experiments were performed in anaesthetised monkeys (Macacca fascicularis) to see if the inhibitory effect of indomethacin was reversible. Exogenous prostaglandin (PGE2) infusion resulted in a marked calciuretic response without producing changes in GFR or blood pressure. Selected hypercalciuric patients were treated with indomethacin, which resulted in a significant fall in urinary calcium excretion (P less than 0.001). This clinical and experimental study suggests that PGE2 is the hormone which determines the renal handling of calcium by controlling renal tubular function.
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PMID:The influence of renal prostaglandins on glomerular filtration rate (GFR) and calcium excretion in urolithiasis. 679

Children with neonatal Bartter syndrome (NBS) have hypercalciuria, nephrocalcinosis, and osteopenia. A complex of basic-fibroblast growth factor (b-FGF) and a naturally occurring glycosaminoglycan has been identified in the serum and urine of NBS patients. This complex increases bone resorption in a bone disc bioassay system. Angiotensin II (AT II), which is increased in Bartter syndrome, increases the synthesis of b-FGF by cultured endothelial cells. Addition of 10(-8) M AT II to the bioassay, a concentration reported in Bartter syndrome patients, significantly decreased calcium uptake into bone discs [E/C 0.60 (0.04), P < 0.001 compared with buffer, normal E/C >0.90]. Adding b-FGF monoclonal antibody at 10 microg/ml [E/C 0.90 (0.06), P=NS] or indomethacin [E/C 1.00 (0.03), P=NS] to 10(-8 )M AT II neutralized this effect. In separate experiments, newborn rats were given intraperitoneal injections of AT II. Bone discs from these animals were used in the bioassay system and calcium uptake was markedly reduced compared with discs from rats injected with phosphate-buffered saline [AT II 6.6 x 10(-9), E/C 0.10 (0.04), P<0.001, AT II 3.3 x 10(-8), E/C 0.10 (0.05), P<0.001]. AT II decreases calcium uptake in the bone disc bioassay system. This effect can be abrogated by antibody to b-FGF or prostaglandin synthetase inhibition. These results support the hypothesis that in children with NBS, elevated levels of AT II stimulate local skeletal b-FGF synthesis, with a resultant increase in bone resorption via a prostaglandin-dependent pathway.
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PMID:Angiotensin II reduces calcium uptake into bone. 1464 27

We report a rare case of Bartter's syndrome in a 35-year-old woman with type 2 diabetes mellitus. The patient presented with leg weakness, fatigue, polyuria and polydipsia. Hypokalemia, metabolic alkalosis, and high renin and aldosterone concentrations were present, but the patient was normotensive. Gitelman's syndrome was excluded because of the presence of hypercalciuria, secondary hyperparathyroidism and bilateral nephrocalcinosis. The patients condition improved upon administration of a prostaglandin synthetase inhibitor (acemetacin), oral potassium chloride and potassium-sparing diuretics. Five months later, the patient discontinued acemetacin because of epigastric discomfort; at the same time, severe hypokalemia and hyperglycemia developed. Glucagon stimulation and water deprivation tests were performed. Type 2 diabetes mellitus with nephrogenic diabetes insipidus was diagnosed. To avoid further gastrointestinal complications, the patient was treated with celecoxib, a selective cyclooxygenase 2 inhibitor. This case serves as a reminder that Bartter's syndrome is associated with various metabolic derangements including nephrogenic diabetes insipidus, nephrocalcinosis and diabetes mellitus. When treating Bartter's syndrome, it is also prudent to remember that the long-term use of nonsteroidal anti-inflammatory drugs and potassium-sparing diuretics may result in serious adverse reactions.
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PMID:Bartter's syndrome with type 2 diabetes mellitus. 1925 37