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Query: UMLS:C0032617 (polyuria)
 3,056 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We describe a patient with lithium-induced nephrogenic diabetes insipidus in whom detailed investigations of distal tubular function were performed. Clearance of free water during water diuresis was found to be augmented. This suggests proximal suppression of sodium reabsorption by lithium. Reabsorption of free water during high solute clearance was impaired. Acidification of the urine following ammonium chloride loading was abnormal, and this was corrected by sodium sulfate infusion. The cellular mechanism of lithium was investigated by means of indomethacin, an inhibitor of prostaglandin synthesis. Indomethacin caused a partial reversal of the nephrogenic diabetes insipidus, suggesting that the primary cellular action of lithium may be to inhibit the formation of cyclic AMP in the collecting duct cell, although a direct action of indomethacin in increasing solutes in the renal medulla could not be ruled out. It is possible that the lithium-induced polyuria is partially due to an enhancement by lithium of renal prostaglandin action.
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PMID:Lithium-induced nephrogenic diabetes insipidus: studies of tubular function and pathogenesis. 4 18

30 patients on long-term lithium therapy have been studied. The results are presented of the urinary concentrating ability after water deprivation and the intranasal administration of vasopressin, of the simultaneous determination of glomerular filtration rate (GFR) and effective renal plasma flow (ERPF), of the minimal urine pH after an oral dose of ammonium chloride, and of the urinary beta-2-microglobulin excretion. Mean urine concentration (+/- SEM) after 22 hr water deprivation (= Uosm) amounted to 854 +/- 22 mOsm/kg H2O, mean GFR was 101 +/- 4 ml/min, mean ERPF 360 +/- 18 ml/min, and mean minimal urine pH 4.95 +/- 0.06. In 8 out of 30 patients there was polyuria. In these 8 patients the values were 778 +/- 51 mOsm/kg H2O, 113 +/- 6 ml/min, 415 +/- 33 ml/min and 4.99 +/- 0.08, respectively. Serum levels of beta-2-microglobulin and lysozyme and the urinary excretion of beta-2-microglobulin were normal in all patients. No correlation was established between Uosm and the serum lithium concentration during the test (0.8 +/- 0.05 mmoles/l) nor between Uosm and the average serum lithium level during treatment (0.79 +/- 0.03). GFR was only correlated with age. It was found that administration of indomethacin during the concentration test increased Uosm in these patients. The results suggest that, given proper dosage and surveillance, long-term treatment with lithium is not likely to cause disturbances in renal function.
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PMID:A renal function study in 30 patients on long-term lithium therapy. 4 7

Concentrations of the antidiuretic hormone, arginine vasopressin, were measured in 28 patients with severe hyperglycemia to determine if abnormalities in hormonal regulation of water excretion could contribute to the extreme dehydration of uncontrolled diabetes mellitus. Vasopressin levels were markedly elevated in both nonketotic and ketotic patients, indicating that vasopressin deficiency plays no role in the polyuria that accompanies hyperglycemia. Instead, the observed increases in vasopressin represent an ineffective effort to conserve water in the face of an overwhelming solute diuresis caused by the glucosuria. The reasons for such marked elevations in plasma vasopressin in these diabetic patients are multifactorial. Both groups of diabetic patients had evidence of hypovolemia, which was sufficient in magnitude to stimulate vasopressin release. Furthermore, nausea provided an independent stimulus to vasopressin secretion in many patients. Osmotic stimulation might have resulted from the large fraction of unidentified plasma solutes, but this factor alone was not sufficient to explain the markedly increased concentrations of vasopressin. Whether such elevations in vasopressin could have metabolic and/or hemodynamic effects in uncrontrolled diabetes remains to be established.
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PMID:Plasma vasopressin in uncontrolled diabetes mellitus. 10 67

The authors compared the histochemical characteristics of acid mucopolysaccharides (MPS) of the medulla of the kidney with functional indices of the latter in dogs under conditions of water, osmotic diuresis and in polyuria caused by the administration of heparin. There was seen a correlation between the changes in the MPS staining and the intensity of reabsorption of osmotically free water. On the basis of the results obtained a supposition was put forward that the change in the physico-chemical properties of the MPS served as one of the most significant factors determining the permeability of the medulla structures for the passage of water from the tubular lumina into the interstitium.
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PMID:[The role of renal acid mucopolysaccharides in the mechanism of reabsorption of osmotically free water]. 13 4

Four instances of hydramnion associated with renal anomalies are reported: two patients had obstructive uropathies and two had a neoplastic type of renal dysplasia. In two infants water concentration tests revealed a defect in water-concentrating ability. It is postulated that the observed hydramnion resulted from fetal polyuria. In patients with unexplained hydramnion a search for renal anomalies is indicated.
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PMID:Hydramnion and fetal renal anomalies. 18 88

The diffusional and osmotic water permeability of collecting ducts in isolated papillae of rats' kidneys were measured in papillae taken from normal and lithium pretreated rats. The diffusional water permeability of collecting ducts in papillae from normal rats in the absence of ADH was 4.1 +/- 0.2 (S.E.M.) (n = 18) muM s-1 increasing to 7.2 +/- 0.6 mum s-1 with ADH. Values obtained with lithium (10 mM) in the medium, perfusate or both and in papillae taken from lithium pretreated rats did not differ significantly from the above. The cyclic AMP content of the papillae taken from normal rats was 83 +/- 6 pm mg protein in the absence of ADH and increased to 196 +/- 12 (n = 13) with 500 mu units ml-1 ADH. Lithium 10 mM in the medium did not alter this response. Papillae from lithium pretreated rats had a similar basal level of cyclic AMP but the increment in a lithium (10 mM) medium after ADH was significantly less. These results indicate that the impaired water handling of lithium treated rats is probably not due to a failure of the membrane to increase its permeability to water after ADH. Though lithium does alter the production of cyclic AMP this is not believed to be important regarding any alteration in water permeability. We believe it is probable that lithium interferes with sodium chloride transport at some more proximal nephron segment thereby producing the syndrome of polyuria.
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PMID:The effect of lithium on the permeability response induced in the collecting duct by antidiuretic hormone. 18 85

The antidiuretic and urinary cyclic AMP response to supramaximal vasopressin infusion was studied in normal rats and in rats with lithium-polyuria. The animals were anaesthetized and then infused with a solution designed to produce excessive water diuresis and to lower basal cyclic AMP excretion. In 6 control animals not infused with vasopressin (1) urinary cyclic AMP excretion decreased during the infusion period. Vasopressin infusion (300 muU/min.) consistantly induced antidiuresis in all of 13 control rats (II); but the urinary cyclic AMP response varied individually from a significant increase in 6 animals to either no change or to a decrease in the remaining animals. The antidiuretic response to vasopressin was inhibited by 85% in 10 animals with marked polyuria induced by lithium administration (III). None of the animals in this group showed a significant increase of cyclic AMP excretion in response to vasopressin. The average rate of cyclic AMP excretion, which was equal in the two groups before vasopressin, was signifimantly lower in group III than in group II during vasopressin infusion. It is suggested that the increase in cyclic AMP excretion during vasopressin antidiuresis, although not consistant, most likely reflects hormone-induced changes of intracellular cyclic AMP levels in the renal medulla. Thus, the data suggest that the nephrogenic diabetes insipidus syndrome produced by lithium is associated with a defect in the renal formation of cyclic AMP in response to vasopressin.
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PMID:Antidiuretic and urinary cyclic AMP response of vasopressin in normal rats and in rats with lithium-polyuria. 19 Aug 61

The benefits of parenteral feeding need no longer be emphasised. However, qualitative and quantitative food supplements raise a certain number of difficulties which should be better known. Infection is the most frequent complication. It may be avoided by strict aseptic precautions throughout parenteral feeding. Hypoglycemia is a major risk owing to the possible consequence. Hyperglycemia and its consequence of osmotic polyuria is more frequent and should be controlled to avoid loss of water and salt. Complications due to the use of lipid emulsions are exceptional when soya oil is used. Hypophosphoremia should be corrected by increasing phosphate intake. Hypocalcemia is common; it is often associated with hypoproteinemia and sometime a low calcium intake, vitamin D deficiency or a sudden increase in phosphate intake. Vitamin deficiencies, hypomagnesemia, and oligo-element deficiencies should be correcty by appropriate supplements.
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PMID:[Parenteral feeding. Prevention of complications in adults during exclusive mid-term parenteral feeding]. 19 99

Hypothalamic lesions occasionally lead to excessive hypernatraemia and hyperosmolarity which cannot be explained by defective ADH secretion alone. As osmoregulation is a complex system the clinical features differ widely from one patient to another. In general central dysregulation of osmolarity is due to diffuse hypothalamic lesions, e.g. inflammatory inflammatory infiltration by histiocytosis X or by large suprasellar tumours. We report on a ten-year-old girl suffering from a suprasellar spongioblastoma and a twelve-year-old-girl, who had been operated for a large craniopharyngioma. Polyuria and polydipsia were not present. Whereas one patient presented hypernatraemic crises and showed normal osmolarity at the intervals, the other patient suffered from sustained hypernatraemia and hyperosmolarity. In the first patient water loading led promptly to clinical and laboratory normalisation. In the other case water loading failed to decrease hyperosmolarity but led to oedema. In the first patient hypernatraemic crises were combined with decreased serum potassium levels and elevated urinary aldosterone excretion. Therefore acute and long-term trials of spironolactone treatment were successful. Exogenous ADH-derivatives failed to normalize hyperosmolarity. In the other patient, however, DDAVP decreased the serum sodium level seen with small doses.
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PMID:[Hypothalamic hyperosmolarity in childhood (author's transl)]. 31 68

Angiotensin II is dipsogenic, and vasopressin (ADH) regulates renal water excretion. Together, these hormones govern overall mammalian water balance. The Brattleboro rat with inherited diabetes insipidus (DI) lacks ADH and is therefore a convenient model with which to elucidate mechanisms regulating water metabolism. In the present studies, angiotensin II has also been removed from DI rats by the administration of an inhibitor (captopril, SQ 14225; D-2-methyl-3-mercaptopropanoyl-L-proline) of the enzyme which converts angiotensin I, the relatively inert component of the renin-angiotensin system, to angiotensin II, the biologically active substance. SQ 14225 reduced the drinking rates, and after 6 days lowered peripheral plasma aldosterone concentrations were associated with hyperkalaemia. We conclude that the polydipsia of diabetes insipidus partly results from elevated plasma renin activities and angiotensin II concentrations seen in this syndrome. Further, the apparent hypoaldosteronism of DI Brattleboro rats reflects differences in both tissue usage of the steroid and adrenocortical sensitivities associated with polyuria, hyperosmolarity and possibly potassium wasting.
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PMID:Captopril (SQ 14225) depresses drinking and aldosterone in rats lacking vasopressin. 38 37


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