Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020437 (hypercalcemia)
 10,293 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rhesus monkey (Macaca mulatta) were subjected to hypercalcaemia by daily intramuscular injections of vitamin D2 (100,000 IU) and by providing them gram soaked in 1% CaCl2 solution for eating and 1% CaCl2 solution (prepared in tap water) for drinking. After 10, 15, 20 and 30 days of such treatment the serum calcium level recorded a rise (18.24 +/- 0.56, 26.20 +/- 1.30, 17.25 +/- 0.25 and 20.50 +/- 0.55 mg/dl respectively) as compared to those of control animals (12.80 +/- 1.00, 12.30 +/- 0.50, 12.70 +/- 0.20 and 12.30 +/- 0.30 mg/dl). Serial sections of thyroid parathyroid complex and isthmus were subjected to selective staining for lcalising the C cells. The structure and behaviour of these cells both under normal and experimental conditions has been studied. Hypercalcaemia resulted in the increase of these cells. Mitotic figures of the C cells were also encountered after 10 days of hypercalcaemia. The specimens subjected to 30 days treatment showed complete degranulation of these cells. Chronic hypercalcaemia inhibits the activity of parathyroid cells which display degenerative changes. The anterior and posterior poles, the peripheral regions of thyroid and isthmus are completely devoid of calcitonin cells.
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PMID:Thyroid calcitonin cells and parathyroid gland of the Indian rhesus monkey Macaca mulatta in response to experimental hypercalcaemia. 11 36

The effect of the light-darkness cycle on the efficiency of the ultimobranchial and parathyroid glands in altering duodenal calcium transport and plasma and urinary concentrations of calcium was examined in the adult male frog (Rana pipiens). Frogs were unfed, but were allowed access to 0.05 M-CaCl2 in the surrounding medium after ultimobranchialectomy or parathyroidectomy. Calcium transport, as assayed by the everted gut-sac technique, was increased in ultimobranchialectomized frogs at sunrise, concomitant with acute hypercalcaemia and hypercalciuria. An opposite but chronic response was observed in parathyroidectomized frogs with intact ultimobranchial glands. The maximum response observed at sunrise occurred when the concentration of calcium in the plasma of control frogs was decreasing; the minimum response, which occurred 6 h after sunrise, was coincident with a diurnal peak in the concentration of calcium. Vitamin D3 (500 microgram/frog) enhanced calcium transport in ultimobranchialectomized frogs, which resulted in chronic hypercalcaemia and hypercalciuria. The results suggest that diurnal variations in the plasma concentration of calcium do not initiate ultimobranchial activity, but are a response to endocrine control synchronized with the transition from darkness to light.
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PMID:Diurnal variations in the influence of the ultimobranchial glands on calcium homeostasis in the frog (Rana pipiens). 21 89

Renal handling of phosphorus was studied in the following groups of parathyroidectomized rats with maleate-induced Fanconi syndrome: 1) 6 rats receiving intravenous parathyroid hormone, 2) 6 rats receiving intravenous dibutyryl cyclic AMP (DBcAMP), 3) 6 rats undergoing volume expansion with saline, 4) 12 rats receiving intravenous 25 (OH)vitamin D3, 5) 12 rats with acute hypercalcemia induced by intravenous CaCl2, 6) 6 rats with phosphate deprivation, and 7) 6 rats receiving intravenous calcitonin. Parathyroid hormone and calcitonin failed to increase the urinary excretion of both cAMP and phosphorus. Likewise, DBcAMP failed to increase the urinary excretion of phosphorus. Extracellular volume expansion and hypercalcemia (serum calcium 12.9 +/- 0.7 mg/100 ml) did not alter the tubular reabsorption of phosphorus. In phosphate-deprived animals, the fractional excretion 0.16 +/- 0.05 (mean +/- SE) was lower than that in the control animals (maleate-treated without phosphate depletion), 0.46 +/- 0.04 (P less than 0.001). 25 (OH)vitamin D3 decreased the fractional excretion of phosphorus from 0.39 +/- 0.03 in the control (maleate-treated not receiving 25 (OH)vitamin D3) to 0.23 +/- 0.02 (P less than 0.001) in the experimental animals. The present study demonstrated an antiphosphaturic effect of 25(OH)vitamin D3 in experimental Fanconi syndrome; the mechanism of this action is not well understood.
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PMID:Antiphosphaturic action of 25 (OH) vitamin D3 in experimental Fanconi syndrome. 21 76

Long term hypercalcaemia was induced in F. pennanti by alternate day intramuscular injections of 50,000 IU of vitamin D2 and by giving them 1% CaCl2 solution prepared in tap water to drink. The controls were not injected with vitamin D2 and were given tap water. The serum calcium levels at various stages of the experiment (1-29 days) show increased values as compared with those of control animals. The calcitonin cells in the treated animals generally exhibit an increase in their number up to the 15th day. Mitotic figures are also encountered between the 7th and the 15th day of treatment. This exhibits the increase in the number of C cells. Constant calcium challenge results in increased quantities of secretory granules among these cells up to the 15th day and in degranulation from the 17th day onwards. It also causes degenerative changes in a certain number of C cells. The parathyroids exhibit atrophic changes (25 days onwards) due to chronic hypercalcaemia. For short term hypercalcaemia, animals were injected intravenously with 1 ml of 10% solution of calcium gluconate. The calcitonin cells do not exhibit any change during the first half hour but thereafter they exhibit progressive degranulation, resulting in marked degranulation after 5 hours of the injection. The parathyroids remain unaffected throughout the experiment and show no histological change.
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PMID:Studies of calcitonin cells and parathyroid glands of the Indian palm squirrel, Funambulus pennanti in response to experimental hypercalcaemia. 31 55

1. A denervated 'auto-transplanted' dog's kidney preparation was developed to study renin release into renal plasma and lymph. The function of the 'transplant' was compared with that of its partner. In the 'basal' state it had a similar rate of plasma and urine flow, Na, Ca, Mg and Cl excretion but a lower rate of glomerular filtration and K excretion and a lower urinary osmolality. In the 'basal' state the 'transplant' did not release renin into plasma, but invariably released it into lymph. 2. Infusions of MgCl2 solutions into the renal artery which raised the renal plasma Mg concentration (PMg) by 0.1-2 m-mole.1.-1 provoked a concentration-related increase in renin release into plasma. This was due to a rise in the veno-arterial renin difference and in the renal plasma flow rate. Blood pressure and Na excretion were unaltered. 3. In other experiments, an increase in PMg of 1.5-2.5 m-mole.1.-1 was also found to increase renin release into lymph. 4. When the plasma Ca concentration was doubled by infusion of CaCl2 into one renal artery, an increase in PMg of 1.5-2.5 m-mole.1.-1 no longer increased renin release into plasma or lymph. 5. When the plasma NaCl concentration was raised by 8-15 m-mole.1.-1 by infusion of hypertonic saline into the renal artery, MgCl2 infusion failed to increase renin release until PMg was raised by more than 3 m-mole.1-1. 6. The results demonstrate that hypermagnesaemia stimulates renal renin release by a mechanism that is independent of the renal nerves, or of any changes in blood pressure or sodium excretion, but which is antagonized by concurrent hypercalcaemia or hypersalaemia. The possibility is discussed that Mg is reabsorbed from the tubular into the interstitial fluid where it antagonizes the action(s) of Ca on renin release from the juxtaglomerular cells.
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PMID:The effect of increasing the plasma magnesium concentration on renin release from the dog's kidney: interactions with calcium and sodium. 36 8

The UBB of Notopterus notopterus is a paired structure situated between the oesophagus and sinus venosus. Both right and left lobes of the gland are enveloped by a common thick connective tissue which gets constricted between the lobes and separates them. Numerous follicles of varying sizes are encountered in each gland. In N. notopterus the effects of hypercalcaemia (caused by keeping the specimens in 0.5% of CaCl2 solution and by injecting 4000 I.U. of vitamin D2 on alternate days) on UBB has been observed. The effects of NaCl rich environment (created by keeping the fish in 0.5% NaCl solution) on this gland has also been studied. In the UBB of N. notopterus the activity of the gland is observed in terms of: 1. increase in the blood supply of the gland and the dilation of the blood vessel, 2. increase in the height of the follicular epithelium, 3. cytoplasmic hypertrophy resulting in the increase in secretory processes, 4. appearance of pseudostratified epithelium in place of single layered cuboidal follicular epithelium and 5. nuclear and cellular hypertrophy. According to these characteristics it is evident that the gland from group II shows gradual activity from the 2nd day onwards and is maximum on the 6th day. From 8th day to the close of the experiment gradual inactivity of the gland is discerned--follicles get atrophied and the cells appear in clumps. The gland from group III shows a good response to its environment and is more hypertrophied as compared to that of group II. The activity of the gland closely parallels serum sodium levels which increase up to the 8th day when UBB shows the maximum activity. The serum sodium level rises from a normal of 110 m eq/l to a peak of 180 m eq/l on 8th day. After 10 days onwards the gland shows gradual inactivity and degeneration. The serum sodium level is 130 m eq/l on 12th day. These observations support the view that the main role of UBB in N. notopterus lies in sodium metabolism and it is only partially responsible for calcium regulation.
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PMID:Ultimobranchial body of Notopterus notopterus in relation to calcium and sodium rich environments. 52 84

1. Hypercalcemia was induced in S. murinus by alternate day intramuscular injections of vitamin D (25 000 IU) and by providing them 1% CaCl2 solution (prepared in tap water) for drinking. 2. After such a treatment the serum calcium values recorded a rise as compared to those of the control specimens. 3. The histological picture of the thyroid of the treated specimens reveals increased number of calcitonin cells. This observation is supported by the occurrence of mitotic figures among them. 4. Perpetual calcium challenge results in degranulation of the secretory material (calcitonin) among these cells (at 26th and 30th day of treatment). 5. It also results in degenerative changes in certain number of C cells. 6. The blood capillaries around these cells get dilated and secretory granules of C cells tend to gather at the periphery of cytoplasm and towards vascular pole. 7. The parathyroid shows atrophic changes.
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PMID:Studies of calcitonin cells and parathyroid gland of house shrew, Suncus murinus in response to experimental hypercalcemia. 53 67

Parathyroid hormone (PTH) secretion rate was measured in 16 anesthetized calves by using a technique involving radioimmunoassay of parathyroid venous blood which was collected during timed intervals and measured volumetrically. The calves ranged in age from 2-14 weeks. Plasma calcium concentration was altered by infusion of solutions of CaCl2 or disodium ethylenediamine tetracetate (Na2 EDTA) into the jugular vein. When plasma calcium concentrations exceeded 10.5 mg/100 ml, a basal, non-suppressible secretion rate of 0.3 ng/kg/min was maintained despite the induction of hypercalcemia. Slight changes in secretion rate were observed in response to changes of plasma calcium in the range between 9 and 10.5 mg/100 ml. Below 9 mg/100 ml, a small decrease in plasma calcium concentration evoked a pronounced increase in secretion rate. A maximal secretion rate of about 5.5 ng/kg/min was attained at a plasma calcium concentration of approximately 7.5 mg/100 ml and it was not increased by more severe hypocalcemia. These observations confirm the sigmoidal relationship between PTH secretion rate and plasma calcium concentration which was previously suggested by measurement of PTH concentration in peripheral plasma of hypocalcemic, parturient cows.
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PMID:Sigmoidal relationship between parathyroid hormone secretion rate and plasma calcium concentration in calves. 74 6

Hypercalcemia produced in normal volunteers by intravenous infusions of CaCl2 increased outputs of pancreatic enzyme and gastric acid. Further, hypercalcemia enhanced cholecystokinin (CCK)-stimulated pancreatic enzyme secretion and gallbladder contraction. Our results suggest that hypercalcemia affects pancreatic, gallbladder, and gastric functions as well as their responses to exogenous CCK.
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PMID:The influence of hypercalcemia on basal and cholecystokinin-stimulated pancreatic, gallbladder, and gastric functions in man. 95 90

Long-term hypercalcemia induced in rats by administration of vitamine D3 and CaCl2 for 60 days resulted in strong hyperplasia and hypertrophy of C-cells. The extent of hyperplasia varied greatly in individual animals. Histochemical reactions, especially the masked metachromasy with toluidine blue, demonstrated cell groups in which no reaction was observed beside those exhibiting a very strong reaction. Impregnation with silver according to Cajal showed a diminished number of argyrophilic granules in the C-cells, which had undergone hyperplasia. The reactions for non-specific esterases and cholinesterases were similar both in the experimental animals and in the controls. An enlargement of the C-cell nuclei in the experimental group was also pronounced. The total serum calcium level was only slightly increased in this group. It is concluded that the results of staining and the enlargement in nuclear volume of C-cells reflect the increased activity of these cells. Hyperplasia of the C-cells may represent a type of adaptation of the endocrine system in order to maintain calcium homeostasis.
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PMID:The response of thyroid C-cell system in rat to long-term hypercalcemia. 97 6


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