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)

An analysis of the development of the vitellogenic process following artificial hibernation in the lizard Lacerta vivipara was undertaken. For that purpose, organ weights (ovaries, oviducts, liver, fat bodies) and plasma concentrations of total proteins, calcium, and estrogens were monitored. The induction of the vitellogenic growth of 2-5 oocytes per ovary was characterized by a rapid increase in calcemia (from 2.4-2.6 mM to 4-10 mM), and in oviduct and liver weights. During the active and continuous phase of vitellus incorporation (congruent to 3 weeks, follicle diameter 1.6-2.0 mm to greater than 5 mm) the developments of ovaries and oviducts were positively correlated, liver weight and calcemia remained elevated (respectively, 1.2-2.2 times and 2.5-3.5 times the previtellogenic values). Ovulation was preceded by a significant rise in calcemia and followed by a decrease in liver weight, but no modification of oviduct mass. Plasma concentration in total proteins (50-60 mg/ml) was not modified during the entire process. Plasma estrogens were difficult to measure in this small species. Levels of estradiol-17 beta were very often below the assay sensitivity (less than 0.3-0.6 ng/ml), never above 2 ng/ml, and very variable among individuals. No correlation with vitellogenin production could be established. Therefore, the abilities of different ovarian steroids to induce vitellogenin synthesis were tested in vivo. To reduce the rise of plasma estradiol titer (observed during a 4-week experiment), the steroids were implanted in ovariectomized lizards for a short time (5 days). The vitellogenic response was assessed by measuring the distribution of the 32P radioactivity between the acidoprecipitable plasma fraction and the plasma vitellogenin recognized by the lizard antivitellogenin serum. Plasma titers of estradiol-17 beta were monitored. The estrone potencies could not be determined as this treatment involved an important rise in estradiol level. Progesterone, delta 4, testosterone, and 5 alpha-androstanediol were unable to stimulate vitellogenin synthesis. Estradiol-17 beta was the only effective steroid. It was further demonstrated that the estradiol-induced hypercalcemia, hyperproteinemia, and liver growth in ovariectomized lizards were dependent upon the total amount of estrogen injected.
Gen Comp Endocrinol 1986 Jul
PMID:Vitellogenesis in the lizard Lacerta vivipara jacquin. II. Vitellogenin synthesis during the reproductive cycle and its control by ovarian steroids. 377 Apr 43

Sodium-retaining activity of chum salmon prolactin (PRL) was examined in several euryhaline teleosts. Chum PRL was 100 times more potent than ovine PRL in maintaining plasma sodium levels in the hypophysectomized killifish, Fundulus heteroclitus, transferred from 50% seawater to fresh water. The effects of PRLs were parabolic, high doses of the hormones being less effective than low doses. When injected into seawater-adapted fry of the ayu, Plecoglossus altivelis, or into juvenile rainbow trout, Salmo gairdneri, adapted to 50% seawater, a dose-dependent increase in plasma sodium was observed. Chum PRL was 2-10 times more active than ovine PRL, and the effects in the ayu were also parabolic. An increase in plasma sodium also occurred when the PRLs were injected into the seawater-adapted eel, Anguilla japonica; the chum and ovine PRLs were equipotent, and hypercalcemia was also observed. In contrast, both chum and ovine PRLs were without effect on plasma sodium levels of chum salmon fry, either when injected into seawater-adapted fish kept in seawater or into fish subsequently transferred to fresh water. The absence of an effect of PRLs in chum salmon fry seems to be due, at least in part, to their good osmoregulatory ability during the period of seaward migration; effects of the exogenously administered PRLs may be compensated for by other hormones responsible for their hydromineral balance.
Gen Comp Endocrinol 1986 Aug
PMID:Sodium-retaining activity of chum salmon prolactin in some euryhaline teleosts. 378 Dec 35

The dopamine agonist, bromocriptine, was studied with respect to its effects on PTH secretion and calcium homeostasis in Sprague-Dawley rats made azotemic by either total or subtotal nephrectomy. The oral or intraperitoneal administration of 0.25 mg of bromocriptine resulted in a significant increase in the serum calcium concentration when compared to animals given placebo. Bromocriptine produced no significant change in the BUN or the serum concentrations of creatinine, inorganic phosphate or PTH. The mechanism of the hypercalcemic effect of bromocriptine in azotemic rats is unknown. The hypercalcemia may, however, be due to stimulation of PTH secretion, since PTH levels in the serum were inappropriately high for the corresponding levels of calcium.
Gen Pharmacol 1985
PMID:Effect of bromocriptine on serum PTH, calcium and phosphate levels in azotemic rats. 397 99

Injection of about 1 ng/g body wt per day of either vitamin D3 or 1,25-(OH)2-vitamin D3 for 7 days induces hypercalcemia and hyperphosphatemia in fed American eels, Anguilla rostrata, but only hyperphosphatemia in unfed eels. These same analogs also stimulated the uptake of 45Ca from intestinal sacs in situ. The vitamin D3 appeared to be relatively more effective than the 1,25-(OH)2D3 metabolite and chlorpromazine inhibited the effect of vitamin D3 on intestinal calcium uptake. 7-Dehydrocholesterol, vitamin D2, and 24,25-(OH)2D3 did not stimulate hypercalcemia, hyperphosphatemia, or intestinal calcium uptake.
Gen Comp Endocrinol 1984 Sep
PMID:Effect of various vitamin D analogs on plasma calcium and phosphorus and intestinal calcium absorption in fed and unfed American eels, Anguilla rostrata. 608 57

In Sarotherodon mossambicus prolactin cell activity is related to ambient Ca2+ levels, and prolactin has hypercalcemic activity in this species. To study whether prolactin has a direct action on calcium metabolism, or whether prolactin's relationship with calcium is indirect and connected with control of gill permeability, the effects of external Ca2+ and Mg2+ on prolactin secretion and gill permeability were compared. It appeared that high external Mg2+ was associated with reduced prolactin secretion, even though high Mg2+ resulted in a marked hypocalcemia. Exposure of fish to high Ca2+ levels led to hypercalcemia. Both high Mg2+ and high Ca2+ concentrations in the ambient water reduced the osmotic water permeability of the gills. These results represent further evidence that prolactin secretion in S. mossambicus may be affected by any external factor that interferes with branchial permeability. It is concluded that prolactin's main function in this species is connected with control of branchial permeability rather than calcium metabolism, although internal calcium may be implicated in permeability control.
Gen Comp Endocrinol 1983 Nov
PMID:Effects of external Mg2+ and Ca2+ on branchial osmotic water permeability and prolactin secretion in the teleost fish Sarotherodon mossambicus. 665 34

We have used antiserum to human parathyroid hormone-related protein (PTHrP) (1-16) to examine tissues and plasma of the dogfish (Scyliorhinus canicula) for the presence of immunoreactive PTHrP (irPTHrP). The plasma contained high concentrations of irPTHrP (9.34 +/- 0.37 pM), comparable to levels in humans with hypercalcaemia of malignancy. Other tissues with irPTHrP included brain neurones; epithelial cells of the saccus vasculosus, kidney, rectal gland and choroid plexus; and cells of the pituitary pars distalis. PTHrP was not detected in gut, skin, oviduct, and gill epithelia, nor in branchial cartilage. The principal source(s) of plasma PTHrP is not known.
Gen Comp Endocrinol 1995 May
PMID:Immunodetection of parathyroid hormone-related protein in plasma and tissues of an elasmobranch (Scyliorhinus canicula). 763 75

Naked mole-rats have no access to obvious sources of vitamin D and therefore have an impoverished vitamin D status. In an investigation into the effects of vitamin D supplementation, inadvertently supraphysiological doses of 130,000 times the normal dose of vitamin D were administered. Within 5 days animals appeared lethargic, with reduced food intake. All but one of the seven animals were killed and blood was collected. Plasma vitamin D metabolites 25(OH)D and 1,25(OH)2D and calcium were determined. Both vitamin D metabolite concentrations exceeded the upper limits of sensitivity of the assays (> 100 ng/ml 25(OH)D and > 210 pg/ml 1,25(OH)2D). Active calcium uptake in the intestine was evident along with concomitant increases in calcium concentration in plasma, bone, and teeth. The remaining animal survived, but showed scab-like formations in the skin around the lower jaw and along the nipple line. X-ray analyses revealed calcium deposition in these cornified regions, although there was no evidence of metastatic calcification in other tissues. Deposition of excess calcium in skin that is regularly sloughed off and in teeth that are continuously worn down and replaced may reduce the vitamin D-induced hypercalcaemia and thus alleviate the effects of vitamin D intoxication.
Gen Comp Endocrinol 1995 Jul
PMID:Vitamin D3 intoxication in naked mole-rats (Heterocephalus glaber) leads to hypercalcaemia and increased calcium deposition in teeth with evidence of abnormal skin calcification. 765 55

Salmon calcitonin was administered intraperitoneally (0.1, 10, 1000 ng/100 g of fish) to freshwater-adapted, immature, female brown trout, Salmo trutta, and changes in serum calcium levels were determined. The lowest dose (0.1 ng) had an effect similar to injection of saline (control), but the higher doses produced hypercalcemia. These latter effects were associated with increased serum levels of calcitonin. Maintaining immature brown trout in waters containing 20 and 50 mM calcium chloride resulted in a significant lowering of serum calcitonin with time although serum calcium levels remained stable. The extent of the decrease in serum calcitonin increased with the higher levels of environmental calcium.
Gen Comp Endocrinol 1995 Jan
PMID:The effects of calcitonin on serum calcium levels in immature brown trout, Salmo trutta. 771 82

The present data reveal that (a) the Stannius corpuscles (CS) of Ompok bimaculatus are active even in their natural freshwater environment (0.4 mM Ca2+/liter) and produce hypocalcemic hormone or stanniocalcin, which lowers the Ca level in normal freshwater fish injected with 0.2 ml of CS extract (1 mg of CS) per fish, (b) this hypocalcemic activity is enhanced in fish that are adapted to a calcium-rich environment (0.6% CaCl2 solution), and (c) adaptation to this calcium-rich environment leads to hypercalcemia in fish. Administration of the extract (from fish previously reared in 0.6% CaCl2 medium) to hypercalcemic fish leads to severe hypocalcemic conditions. It is suggested that the CS of O. bimaculatus produce a general hypocalcemic hormone which is active in the natural freshwater environment (with 0.4 mM Ca2+/liter) and whose activity is enhanced under hypercalcemic conditions after adaptation to a calcium-rich habitat.
Gen Comp Endocrinol 1994 May
PMID:Evidence for general hypocalcemic hormone from the stannius corpuscles of the freshwater catfish Ompok bimaculatus (Bl). 792 28

An in vivo whole animal 45Ca influx bioassay was used to study the cholinergic control of the release of stanniocalcin (STC) in the rainbow trout (Oncorhynchus mykiss) and the American eel (Anguilla rostrata). In both species calcium influx (JinCa2+) was lowered in response to hypercalcemia induced by intravascular (trout) or intraperitoneal (eel) injections of CaCl2. In trout, this response was blocked by the cholinergic antagonist atropine (0.25 mumol kg-1) and mimicked by the cholinoceptor agonist carbachol (0.25 mumol kg-1). These observations are consistent with a cholinergic stimulation of STC release in response to hypercalcemia in trout. In eels, pretreatment with atropine did not block the lowering of JinCa2+ in response to hypercalcemia. This suggests that cholinergic stimulation is not obligatory for stanniocalcin release in eels. However, carbachol treatment did elicit STC release as revealed by the lowering of JinCa2+. This response to carbachol was not observed in stanniectomized eels. Thus, in the American eel it appears that there is a potential for cholinergic control of STC release but that other factors such as the local plasma calcium concentration may also be involved, at least in response to severe acute hypercalcemia.
Gen Comp Endocrinol 1994 Apr
PMID:Cholinergic control of stanniocalcin release in the rainbow trout, Oncorhynchus mykiss, and the American eel, Anguilla rostrata. 804 58


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