Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Male Swiss OF1 mice received a single oral dose of either 80 mg/kg hexachloro-1,3-butadiene (HCBD) or 40 mg/kg methyl mercury (MeHg). Examination of cryostat kidney sections stained for alkaline phosphatase (APP) revealed damage to about 50% of the proximal tubules after 8 h. Treatment with the organic anion transport inhibitor probenecid (i.p., 3 x 0.75 mmol/kg) did not have any renal effect in normal mice but reduced the number of damaged tubules by 80 and 90% in mice treated with HCBD and MeHg respectively. The results support the conclusion that the toxicity of HCBD and MeHg to the mouse kidney is related to a probenecid-sensitive transport process. It cannot be stated from the present investigation whether the inhibition nephrotoxicity data are related to classic organic anion secretion by the kidney.
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PMID:Probenecid-induced protection against acute hexachloro-1,3-butadiene and methyl mercury toxicity to the mouse kidney. 334 Oct 50

The protective effect of selenite, seleno-dl-methionine and biological selenium against the renotoxicity of mercury was tested in rats. As the source of biological selenium, the liver soluble fraction of rats given 60 mumoles/kg selenite 3 days before sacrifice was used. The aim of the experiments was to test whether protective efficiency follows the reported order of ability to form HgSe. Mercury was given subcutaneously in doses of 2.5, 5.0 and 7.5 mumoles/kg HgCl2 and selenium was given in equimolar doses at the same time as Hg2+. Liver soluble fraction, biological selenium or liver soluble fraction supplemented with selenite or seleno-dl-methionine were given orally, while in experiments without liver soluble fraction the two selenium compounds were given subcutaneously. Biological selenium was tested only at the two lower dose levels. Both biological selenium and seleno-dl-methionine decreased the urinary excretion of mercury in the first 48 h, but less so than selenite and only selenite decreased the renal content of mercury at the end of this period. Urinary alkaline phosphatase activity and plasma urea nitrogen at the 2.5 and 5.0 mumoles/kg dose levels decreased in the order of no selenium greater than biological selenium greater than seleno-dl-methionine greater than selenite. As the reported HgSe formation increases in the same order, the experiments support the role of HgSe formation in the protective effect. The degree of necrotic damage in the P2 and P3 regions of the proximal tubular cells increased in the same order as the biochemical indicators at the 5.0 and 7.5 mumoles/kg dose levels.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Comparison of the protection given by selenite, selenomethionine and biological selenium against the renotoxicity of mercury. 366 17

Interaction of purified human liver and placental alkaline phosphatases (orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1) with sulfhydryl groups, sulfhydryl reagents, and Mg2+ were studied. L-Cysteine (0.1 mmol/l) or Mg2+ activated the liver enzyme 4-5-fold and the placental enzyme 2-3-fold, with optimal pH 7.5-8.0; these activations were not additive. L-Cysteine (2 mmol/l) inhibited both enzymes maximally at pH greater than 9.0; phosphate protected the enzymes. S-Methylcysteine had little effect, with or without Mg2+. Inhibition by sulfur-containing compounds paralleled their ability to bind Zn2+. Fluoresceine mercury acetate (specific for sulfhydryl groups) inhibited the isoenzymes, whereas iodoacetic acid, iodoacetamide, dithionitrobenzoic acid, and p-chloromercuribenzoate had little effect. The inhibition was reversed by L-cysteine and only slightly protected by inorganic phosphate. Thus, there are two sites on human liver and placental alkaline phosphatase that interact with L-cysteine; a Mg2+-binding site, which results in activation, and a site that involves one or both of the bound Zn2+ ions and results in inactivation. Both enzymes have a protected essential thiol group.
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PMID:Modulation of activity of human alkaline phosphatases by Mg2+ and thiol compounds. 394 54

The acute renotoxicity of HgCl2 and phenylmercuric acetate (PhHgAc) was compared at two intraperitoneal dose levels: 0.5 and 1.0 mg Hg/kg. There was no difference in the type of proximal tubular damage caused by the two mercurials, but 1.0 mg Hg/kg as PhHgAc produced approximately the same degree of damage as 0.5 mg Hg/kg as HgCl2. At the selected dose levels only HgCl2, but not PhHgAc increased the urinary excretion of alkaline phosphatase. At 12 and 24 h after PhHgAc the content of mercury was higher in blood and lower in the kidneys and urine than after the administration of equimolar doses of HgCl2. As the difference in the rectal mercury contents of HgCl2 and PhHgAc treated groups declined with time, difference in renotoxicity seems to relate only to renal mercury taken up within 24 h of administration. It is suggested that the slower renal extraction of mercury - as in regenerating kidneys (Tandon and Magos 1980) - was responsible for the lower degree of renotoxicity in phenylmercury treated rats.
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PMID:The comparative renotoxicology of phenylmercury and mercuric chloride. 621 15

Chronic mercuric chloride intoxication in an aged horse given 0.8 mg Hg/kg/day for 14 weeks was manifest by signs of progressive respiratory difficulty and renal disease. The effects were not self-limiting after mercury was withdrawn, and the animal was destroyed six weeks later. Renal function changes included heavy glycosuria, modest proteinuria, phosphaturia, reduced urine osmolality, gradually increasing urine production, reduced glomerular filtration rate, and terminally, azotemia. The condition bore similarities to the Fanconi syndrome in man. Urinary gamma-glutamyl transpeptidase, alkaline phosphatase and amino-aspartate transferase activities were inconsistent indicators of tubular damage in random samples at this dose rate. The pathologic response was characterized by extensive granulomatous infiltration throughout the lungs, in particular, and to a lesser extent in the kidneys, liver and bone marrow. The renal changes included this marked interstitial reaction and proximal tubular degeneration. Mercury levels were negligible in the lungs and highest in the renal cortex. The granulomatous reaction was not encountered in previous mercury toxicity studies in horses and may indicate an individual sensitivity to the agent.
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PMID:Some effects of chronic mercuric chloride intoxication on renal function in a horse. 621 26

In vitro effects of four sublethal concentrations (0.10, 0.40, 0.80 and 1.20 micrograms) of mercury (hg) on acid, alkaline and glucose-6-phosphatases of liver, kidney and gills of Notopterus notopterus were studied. The maximum (80.76%) significant (P less than 0.001) inhibition in acid phosphatase of gills and minimum (36.66%) significant (P less than 0.05%) inhibition in alkaline phosphatase of kidney was observed at 1.20 microgram and 0.10 microgram Hg concentrations, respectively. EDTA and ascorbic acid (AA) restored the phosphatase activity to the greatest extent when administered with the Hg.
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PMID:In vitro effect of mercury on tissue phosphatases of Notopterus notopterus and the role of EDTA and AA in their restoration. 628 44

The effects of 1.5 ppm of mercuric chloride (LC50/48 hr) on some enzymes and organic substances of liver tissue of Sarotherodon mossambicus were studied. Significant decreases in the activities of succinate dehydrogenases, lactate dehydrogenases, glucose-6-phosphate dehydrogenase, alkaline phosphatase, and acid phosphatase and in the levels of organic substances like total anthrone-positive substances, glycogen, and total ninhydrin-positive substances were observed. The results indicate impaired oxidative and transphosphorylative activities and utilization of carbohydrates during acute mercury toxicosis in fish.
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PMID:Acute effect of mercury toxicity on some enzymes in liver of teleost Sarotherodon mossambicus. 632 40

Male Porton-Wistar rats, 32 weeks old, were given i.p. one of the following doses of HgCl2; 0.5, 1.0 or 1.5 mg Hg/kg. In the preceding 4-week period and throughout the experiment the animals had free access to either tap water or 1.0% saline. The urinary excretion of alkaline phosphatase measured in urine samples, collected during the first 24 h after treatment with mercury, indicated that chronic saline loading significantly attenuated tubular damage caused by 0.5 mg or 1.0 mg Hg/kg, but not by 1.5 mg Hg/kg. Tubular necrosis 12 and 24 h after mercury was also less severe and extensive in saline than in tap water-drinking rats. This difference was still noticeable 4 days after mercury treatment in rats dosed with 0.5 mg Hg/kg, but death in the two higher dose groups prevented further pair-to-pair histological comparison. At the selected dose levels chronic saline loading did not decrease renal mercury content at 12 or 24 h and therefore protection was not associated with decrease in renal mercury uptake. The experiment indicates that chronic saline drinking, which at higher doses attenuates HgCl2-induced acute renal failure but not tubular necrosis, is able to moderate the severity of tubular necrosis when the dose of HgCl2 is as low as 0.5 mg Hg/kg. This protective effect diminishes as the dose is increased.
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PMID:Effect of prolonged saline loading on HgCl2-induced renal tubular damage. 648 35

In this study the problems encountered in staining immunoglobulin (Ig) in sections of paraffin-embedded human lymphoma samples have been investigated. It was found that the "masking' of cytoplasmic Ig, which occurs when tissues are fixed in formol saline (the fixative employed in most previous studies), can be avoided by the use of mercury-based fixatives. When non-Hodgkin's lymphoma samples fixed in this way were studied it was found that cytoplasmic Ig labelling of both lymphoid and histiocytic cells is often attributable to non-specific uptake of serum proteins. This phenomenon probably accounts for a number of published anomalous immunoperoxidase staining results in human lymphoma (e.g. the presence of both kappa and lambda chains in the same neoplastic cell). Double immunoenzymatic labelling (using alkaline phosphatase and peroxidase) proved valuable in the elucidation of this phenomenon. When staining due to absorbed Ig was discounted it was possible to demonstrate monoclonal Ig labelling in seven out of sixteen cases of non-Hodgkin's lymphoma. In each case IgM was found in association with a single light chain type and these results were in agreement with those obtained by direct immunofluorescent labelling of cryostat sections. In a further case u chains without associated light chains were demonstrated by immunoperoxidase staining. Seven cases of Hodgkin's disease were studied by immunoenzymatic techniques. Although IgG was frequently found in Reed-Sternberg and Hodgkin's cells its presence was not attributable to non-specific uptake of serum protein since albumin was absent or only present in small amounts. These findings are in support of the macrophage origin of these cells.
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PMID:An immunohistological study of human lymphoma. 700 85

Mercury is known to modify enzyme activity through oxidation of thiol groups and respective reverse reactions in vitro and in vivo. However, variations in the activity of carbohydrates, and the significance of this variation after mercury poisoning in different species, has not been established. In the present report, the effects of inorganic mercury on selected hepatic enzymes was studied in the freshwater fish Channa punctatus. Quantitative data clearly showed a dose-response relationship between the amount of mercury retained in the liver and inhibition of enzymes (i.e. alkaline phosphatase, glucose-6-phosphatase, amylase, maltase, lactase, lipase and dehydrogenases). Mechanisms and significance of their modification have also been discussed.
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PMID:Co-enzyme effects of inorganic mercury in the liver of a freshwater fish Channa punctatus. 718 6


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