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)

1. To investigate mechanisms of extrarenal buffering in uraemic acidosis, we studied the effects of the carbonic anhydrase inhibitor, acetazolamide, in normal subjects and in patients with end-stage kidney disease on maintenance haemodialysis with virtually no urine output. 2. Acetazolamide (500 mg) was administered daily for 7 days, after pretreatment for 1 month with 1,25-dihydroxyvitamin D (n = 12) or placebo (n = 12); only placebo was administered to a third group (n = 12) of haemodialysis patients. In addition, acetazolamide was administered to normal control subjects (n = 12). 3. Treatment with acetazolamide resulted in a more marked metabolic acidosis in haemodialysis patients than in normal control subjects and the effect in haemodialysis patients was attenuated by prior treatment with 1,25-dihydroxyvitamin D. 4. The administration of acetazolamide to haemodialysis patients led to an increase in serum inorganic phosphorus, bone isoenzyme of alkaline phosphatase and parathyroid hormone, and a reduction in serum calcium, whereas acetazolamide had no effect on these variables in normal subjects. In contrast, in the haemodialysis patients previously treated with 1,25-dihydroxyvitamin D, acetazolamide increased serum inorganic phosphorus, bone isoenzyme of alkaline phosphatase, parathyroid hormone and serum calcium. 5. We hypothesize that the metabolic acidosis induced by acetazolamide in haemodialysis patients may result from interference with the mechanisms of extrarenal buffering. 6. As parathyroid hormone, 1,25-dihydroxyvitamin D and carbonic anhydrase are thought to be involved in bone buffering, we suggest that the marked acidosis seen in haemodialysis patients treated with acetazolamide may be due to impaired parathyroid hormone-mediated bone buffering.
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PMID:Severe metabolic acidosis and disturbances of calcium metabolism induced by acetazolamide in patients on haemodialysis. 215 49

The genetic structure of two Chukot Evens subpopulations (314 individuals) for electrophoretic protein systems and taste sensitivity to PTC was studied. 17 of the 39 loci were polymorphic (43.59%). The following systems were completely monomorphic: diaphorase NAD H (Dia); glucose-6-phosphate dehydrogenase (G-6-PD); glutamatoxalate transaminase (GOT); carbonic anhydrase (Ca-1); catalase (Ct), lactate dehydrogenase (loci LDH-A and LDH-B); leucine aminopeptidase (Lap); malate dehydrogenase (MDH); purine nucleoside phosphorylase (PNP); superoxide phosphorylase (PNP); superoxide dismutase (SOD); phosphoglucomutase-2 (PGM2); cholinesterase (locus E1); red cell esterase (4 loci); albumin (Alb); hemoglobin (Hb A and B); ceruloplasmin (Cp); and blood, gren, using the standard method. The following systems were polymorphic: red cell acid phosphatase (AcP); phosphoglucomutase-1 (PGM1); 6-phosphogluconate dehydrogenase (PGD); glutamatepyruvate transaminase (GPT); glyoxalase-1 (GLO-1); esterase (EsD); adenilatkinase (AK); alkaline phosphatase (Pp); cholinesterase (locus E2); haptoglobin (Hp); transferrin (Tf); group-specific component (Gc) and ABO, MN, Lewis, P blood groups and taste sensitivity to PTC. The following allele frequencies for polymorphic loci have been detected: AKI = 0.994; GLO = 1I = 0.082; GPT1 = 0.653; AcPA = 0.400; AcPB = 0.599; AcPC = 0.001; PGDA = 0.944; PGM1(1) = 0.906; EsD1 = 0.897; E2+ = 0.048; HpI = 0.394; GcI = 0,919; Tfc = 0.987; r(O) = 0.669; p(A) = 0.184; q(B) = 0.146; M = 0.711; Le = 0.411; P1+ = 0.521; t = 0.295. The genetic structure of Chukot Evens population is significantly nearer to that of the other ethnic groups of the North-East, in comparison with the genetic structure of Evenks of the Middle Siberia.
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PMID:[Genetic structure of the populations of native inhabitants in the northeastern USSR. V. The Chukot Evens]. 293 99

Ubiquitin, a unique protein with esterase and carbonic anhydrase activity, has been found to have also a p-nitrophenyl phosphatase activity. This phosphomonoesterase activity of ubiquitin has an acidic pH optimum; its true substrate appears to be the phosphomonoanion, with a Km of 1.8 X 10(-3) M. It is competitively inhibited by the typical acid phosphatase inhibitors, arsenate (Ki = 1.3 X 10(-3) M), molybdate (Ki = 1.2 X 10(-6) M), and phosphate (Ki = 1.4 X 10(-3) M). These inhibitors have no effect on the CO2 hydration and p-nitrophenyl acetate esterase activities of the ubiquitin. Acetazolamide slightly inhibited the p-nitrophenyl phosphatase activity.
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PMID:The p-nitrophenyl phosphatase activity of ubiquitin from bovine erythrocytes. 299 74

The relationships among phosphorus phase feeding, egg shell quality, and the activities and concentrations of several enzymes and minerals in the uterine and isthmus mucosae of hens at the time of oviposition were investigated. During the first 8 months of production (Phase 1), layer diets contained .3, .5, or .7% available phosphorus. Between 9 and 12 months of production (Phase 2), dietary available phosphorus was either increased or decreased by .2% phosphorus, or was left unchanged. No significant differences due to Phase 1 diets were demonstrated for hard-shelled (HS), soft-shelled (SS), or shell-less (SL) egg production, livability, egg weight, or specific gravity. Phase 2 diets had no significant effect on SS or SL egg production, livability, or egg specific gravity; however, decreasing dietary phosphorus reduced egg weight. Levels as high as .9% had no effect on specific gravity or HS egg production, while .1% dietary phosphorus was detrimental to HS egg production and feed consumption. No significant differences due to dietary available phosphorus or egg type (SS vs. HS) were demonstrated for uterine or isthmus mucosal enzyme activities or mineral contents, with one exception. Higher inorganic phosphorus concentrations were found in the uterus of HS egg layers when compared to levels in the uterus of SS egg layers and the isthmus of HS and SS egg layers. Acid phosphatase and carbonic anhydrase activities, and total calcium levels were significantly higher in the isthmus than the uterus, while alkaline phosphatase and pyrophosphatase activities, and inorganic phosphorus levels were significantly higher in the uterus than the isthmus.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Phosphorus phase feeding and uterine and isthmus mucosal enzymes and minerals in relation to soft-shelled and shell-less egg production. 299 45

The role of cyclic adenosine 3',5'-monophosphate (cAMP) in inducing bone resorption was studied in neonatal mouse calvaria in vitro. Forskolin, a stimulator of adenylate cyclase, increased the medium calcium concentration at 96 hr of incubation, indicating enhanced bone resorption. Bone resorption was observed between 1 X 10(-4) and 1 X 10(-6) M forskolin; the maximal effect was at 1 X 10(-5) M and there was no effect at 1 X 10(-7) M. Lactic acid release was increased during the 96 hr of incubation in proportion to the calcium release in the media. The bone acid phosphatase activity was increased and the alkaline phosphatase activity was decreased. Bone carbonic anhydrase activity was increased more than twofold. Forskolin-induced bone resorption was significantly but incompletely inhibited by 10(-4) M acetazolamide, a carbonic acid anhydrase inhibitor. These findings support the concept that carbonic anhydrase plays a significant role in bone resorption.
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PMID:Forskolin-induced bone resorption in neonatal mouse calvaria in vitro. 300 59

The role of carbonic anhydrase in bone resorption induced by parathyroid hormone (PTH) and dibutyryl cyclic AMP (DBcAMP) was studied using an in vitro neonatal mouse half-calvarial culture system. Both PTH (16.7 nM) and DBcAMP (0.3 mM) were effective in stimulating bone resorption, as assessed by measuring changes in media calcium concentrations. Bones treated with PTH or DBcAMP for 96 hr contained significantly greater carbonic anhydrase activity than control bones [PTH Treated/Control (T/C) = 2.44; DBcAMP T/C = 2.34]. Both PTH and DBcAMP significantly enhanced calvarial acid phosphatase activity relative to control values [PTH T/C = 1.48; DBcAMP T/C = 1.30]. Neither PTH nor DBcAMP significantly altered calvarial alkaline phosphatase activity. Bone resorption induced by PTH and DBcAMP was inhibited by the carbonic anhydrase inhibitor acetazolamide, but not by the acetazolamide analog CL 13,850 (N-t-butylacetazolamide), which does not inhibit carbonic anhydrase. These results support the concepts that PTH-induced bone resorption requires the action of osteoclastic carbonic anhydrase and that the action of PTH on bone is mediated, in part, by the action of cyclic AMP.
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PMID:Bone resorption induced by parathyroid hormone and dibutyryl cyclic AMP: role of carbonic anhydrase. 301 20

Equine muscle carbonic anhydrase (CA-III) behaves like ubiquitin in undergoing extensive acylation of N epsilon-lysine residues upon reacting with p-nitrophenyl esters. The enzyme undergoes extensive carbamoylation of lysine residues when reacted with carbamoyl phosphate. The modification of from 6 to 7 lysine residues results in the production of a series of more anodic electrophoretic components. The derivatization of the lysine residues leads to a marked decrease in the enzyme's ability to hydrate CO2. The equine CA-III possesses both acid and alkaline phosphatase activities in contrast to the rabbit which possesses only the former type.
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PMID:Acylation and carbamylation of equine muscle carbonic anhydrase (CA-III) upon reaction with p-nitrophenyl esters and carbamoyl phosphate. 308 46

The calcium absorption and duodenal and uterine vitamin D-dependent calcium-binding protein (CaBP-28K) levels were decreased in hens when eggshell calcification was suppressed by premature expulsion of the egg. Nevertheless, these levels remained higher than those of immature pullets or pullets treated with estrogen. The resumption of shell formation by hens which had previously laid soft-shell eggs was associated during calcification of the first egg with increases in intestinal Ca absorption. CaBP concentration, and alkaline phosphatase activity. The increase in uterine CaBP concentration preceded the stage of rapid calcium deposition. Uterine carbonic anhydrase activity was increased by sexual maturity but not consistently by shell formation. Ablation of the parathyroids just before the resumption of shell formation suppressed the increases in duodenal calcium absorption and CaBP concentration elicited by egg calcification. In contrast, the increase in CaBP level was maintained in the uterus of parathyroidectomized hens, in spite of the decreased shell deposition. Previous studies indicated that increased uterine CaBP associated with eggshell calcification is not elicited by vitamin D. The present study confirms this observation and also shows that these changes are not elicited by either PTH or sex steroid hormones.
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PMID:Effects of suppression and resumption of shell formation and parathyroid hormone on uterine calcium-binding protein, carbonic anhydrase activity, and intestinal calcium absorption in hens. 310 32

To examine the effects on protein and electrolyte reabsorption of reducing the energy supply to the proximal tubules, an inhibitor of the citric acid cycle, maleate (600 mg.kg-1), was administered to anesthetized dogs during continuous ethacrynic acid infusion. One hour after infusion, maleate reduced renal oxygen consumption from 128 +/- 3 to 48 +/- 6 mumol.min-1. Comparisons at similar GFR showed that maleate reduced bicarbonate reabsorption by 65%, chloride reabsorption by 60% and phosphate reabsorption by 90%. Tubular reabsorption of lysozyme, determined by the 'trapped-label' method, was reduced by 97%. Total protein excretion in urine increased from 0.12 to 1.0 mg.min-1 and was not associated with a significant increase in brush border and lysosome marker enzymes. However, by superimposing a carbonic anhydrase inhibitor, acetazolamide (100 mg.kg-1), electrolyte reabsorption was slightly further reduced but protein excretion increased to 2.7 mg.min-1, coincidentally with a dramatic increase in enzyme excretion: approximately 20-fold in the brush border enzymes, alanine aminopeptidase and alkaline phosphatase, and 10-fold in the lysosomal enzymes, acid phosphatase and N-acetyl-beta-glucosaminidase. Our data indicate that maleate stops protein reabsorption without signs of acute tubular damage, whereas subsequent administration of acetazolamide results in tubular desquamation and albumin leakage.
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PMID:Effect of maleate on tubular protein reabsorption in dog kidneys. 323 92

The influence of alimentary zinc deficiency on duration of skin allograft functioning was studied in experiments on guinea pigs. Feeding the animals with a ration deprived of zinc results in significant prolongation of the skin graft functioning period. Thus, in the test group animals that received the ration deprived of zinc the mean time of the graft functioning comprised 24.0 +/- 1.4 days, while in the guinea pigs of the control group that were fed with full value ration, this parameter was 9.9 +/- 0.42 days. At the same time the number of circulating lymphocytes was decreased and their capacity for spontaneous rosette-formation was suppressed in the peripheral blood of the test group animals, as well as manifest inhibition of zinc-dependent enzymes (lactate dehydrogenase, alkaline phosphatase, carbonic anhydrase) in the blood was recorded. Zinc deficiency in the ration induces significant diminution of this trace element content in the muscles, bones, liver, skin and blood, under conditions of its daily negative balance in the body.
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PMID:[Effect of exogenous zinc deficiency on the duration of skin graft functioning]. 329 91


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