Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The "biliary tract" enzymes (leucine aminopeptidase, gamma-glutamyltranspeptidase and 5'-nucleotidase) in serum reflect to varying degrees, obstruction, proliferation, inflammation and neoplasia involving the hepatobiliary duct system. Their use is directed towards two purposes: (1) as non-electrophoretic assays to evaluate the source of an elevated non-specific alkaline phosphatase and (2) to offer greater sensitivity and specificity for space-occuping lesions in the liver. In appropriate clinical states, any of the three enzymes offer these advantages and there is little to chose among them. Selection of the assay to use in the clinical laboratory then becomes based on non-clinical factors, i.e., technical ease, apparent substrate specifities, etc. With these additional factors and despite some shortcomings, our selection is leucine aminopeptidase.
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PMID:The enzymes of the hepatobiliary tract: a biochemical and clinical comparison. 415 29

Serum gamma-glutamyl transpeptidase (GGT) activity correlates closely with the activities of alkaline phosphatase (ALP) and 5'-nucleotidase (5NT) in various forms of liver disease. Maximum elevations of all three enzyme activities are observed in diseases which particularly affect the biliary tract. Compared with the other two enzymes GGT is generally increased to a greater extent and is thus the most sensitive indicator of biliary-tract disease, while estimations of serum GGT are more reproducible than those of 5NT. However, a group of patients who had been treated with phenytoin and barbiturates were found to have elevated serum GGT activities without any other evidence of liver disease. The apparent effect of certain drugs on serum GGT activity indicates the need for caution in interpreting the results of this test.
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PMID:Serum -glytamyl transpeptidase activity in liver disease. 440 86

The release of plasma-membrane-bound enzymes by phosphatidylinositol-specific phospholipase C obtained from Bacillus thuringiensis was investigated. Among the ectoenzymes of plasma membrane tested, alkaline phosphodiesterase I was released markedly from rat kidney cortex slices, in addition to alkaline phosphatase and 5'-nucleotidase. Other membrane-bound enzymes; alanine aminopeptidase, leucine aminopeptidase, dipeptidyl peptidase, leucine aminopeptidase, dipeptidyl peptidase IV, esterase and gamma-glutamyl transpeptidase could not be liberated from the treated slices. Alkaline phosphodiesterase I was released linearly from rat kidney slices with the concentration of phosphatidylinositol-specific phospholipase C, but little enzyme was released from rat liver slices. Alkaline phosphodiesterase I separated from kidney tissue with n-butanol still retained phosphatidylinositol and was transformed into a lower molecular weight form by phosphatidylinositol-specific phospholipase C. This suggests an important function for phosphatidylinositol in the binding of alkaline phosphodiesterase I to the plasma membrane of rat kidney cells. The alkaline phosphodiesterase I released from rat kidney had a molecular weight of about 240,000 and an isoelectric point (pI) of 5.4. The enzyme hydrolyzed the phosphodiester linkage of p-nitrophenyl-thymidine 5'-monophosphate at pH 8.9 and had a Km value of 0.3 mM. The enzyme was activated by Mg2+ and Ca2+, but was inhibited by EDTA. Strong inhibition took place on the addition of adenosine 5'-phosphosulfate or the nucleotide pyrophosphates, i.e., UDP-galactose and alpha, beta-methylene ATP.
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PMID:Release of alkaline phosphodiesterase I from rat kidney plasma membrane produced by the phosphatidylinositol-specific phospholipase C of Bacillus thuringiensis. 609 28

The subcellular distribution in brain capillaries of alkaline phosphatase and Na+, K+-ATPase was investigated by two methods. Cytochemical studies using whole brain perfusion and electron microscopic examination indicated that alkaline phosphatase activity was located in both the luminal and antiluminal cytoplasmic membranes of the brain capillary endothelial cells. By contrast, the K+-dependent phosphatase activity associated with Na+, K+-ATPase was located in only the antiluminal membrane. Biochemical studies using membranes prepared by homogenization of isolated brain capillaries and density gradient centrifugation resulted in identification of two plasma membrane fractions. The light fraction contained alkaline phosphatase but very little Na+, K+-ATPase while the heavier fraction contained both enzyme activities. In addition, gamma-glutamyl transpeptidase showed a distribution similar to alkaline phosphatase while 5'-nucleotidase activity was distributed with the Na+, K+-ATPase activity. We conclude that the luminal and antiluminal membranes of brain capillaries are biochemically and functionally different. This polarity should permit active solute transport across brain capillary endothelial cells which are the cells responsible for the blood-brain barrier.
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PMID:Polarity of the blood-brain barrier: distribution of enzymes between the luminal and antiluminal membranes of brain capillary endothelial cells. 610 38

The lung of adult man contains several times more 5'-nucleotidase (EC 3.1.3.5), alkaline phosphatase (EC 3.1.3.1) and gamma-glutamyl-transpeptidase (EC 2.3.2.2) per gram than does that of the 12- to 16-week fetus. In rat lung, too, there is a drastic developmental rise in these activities. Opposite changes in two of the enzymes occur during hepatic differentiation: alkaline phosphatase decreases in the rat, and gamma-glutamyl-transpeptidase is ten times higher in the fetal than in the adult liver of both species.
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PMID:Pulmonary and hepatic activities of membrane-bound enzymes in man and rat. 610 6

The gamma-glutamyltransferase (gamma-GT) activity decreased by 50% following adrenalectomy of female rats, in homogenate as well as in a purified plasma membrane preparation from liver. In contrast, such a variation was not found in the kidney. None of 3 other enzyme activities of the plasma membrane, namely 5'-nucleotidase, alkaline phosphatase, and alkaline phosphodiesterase I, was decreased by adrenalectomy. Administration of hydrocortisone (5 mg/100 g body weight) resulted in a 2.6-fold increase in hepatic gamma-GT activity from adrenalectomized rats. The hydrocortisone-mediated stimulation of gamma-GT activity was dose- and time-dependent. The 5'-nucleotidase and leucine aminopeptidase activities were not modified by the hydrocortisone treatment. The activity of gamma-GT was mainly associated with nuclear fractions (nuclei and plasma membranes) obtained from liver homogenates of either control, adrenalectomized or adrenalectomized hydrocortisone-treated animals, and this activity was purified 18-fold in a plasma-membrane preparation as compared to homogenate. These data suggest that adrenalectomy and conversely hydrocortisone treatment modulate specifically the hepatic plasma-membrane gamma-GT activity. This represents one of the first demonstrations of a specific modulation by glucocorticoids of an enzyme activity typical of the plasma membrane.
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PMID:In vivo modulation of rat hepatic gamma-glutamyltransferase activity by glucocorticoids. 610 52

1. Proteins of fat-globule membrane from bovine milk were solubilized with the non-ionic detergent Triton X-100 in the presence of protease inhibitors. Approximately 25% of the total membrane protein was solubilized and the extracts were shown to contain a sample of most of the major membrane proteins and glycoproteins. 2. The solubilized proteins were separated in flat-beds of Ultrodex by electrofocusing and the pI values for the major proteins, glycoproteins and certain enzymes determined. Several of the proteins displayed marked heterogeneity indicating the existence of protein variants and isoenzymes. Principal pI values for the enzymes assayed were as follows: xanthine oxidase, 7.35--7.55; NADH2: iodonitrotetrazolium reductase, less than 4.5; 5'-nucleotidase, 7.15--7.4; alkaline phosphatase, 5.4--5.7; phosphodiesterase, 4.6--4.8; gamma-glutamyl transpeptidase, 4.4--4.55. 3. Fractions after electrofocusing were analyzed by 'fused rocket' immunoelectrophoresis and crossed immunoelectrophoresis after separation in polyacrylamide gels containing sodium dodecyl sulphate. Major antigens of the membrane include xanthine oxidase and glycoproteins of apparent molecular weights 67 000, 49 500 and 46 000. The latter two components share common antigenic determinants and could not be separated by gel filtration, ion-exchange chromatography, lectin-affinity chromatography or preparative electrofocusing.
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PMID:Separation of the proteins of bovine milk-fat-globule membrane by electrofocusing with retention of enzymatic and immunological activity. 610 13

Microvessels were isolated from rat brain using a double collagenase treatment which removed the endothelial basement membranes. The isolate was characterized by intact luminal and abluminal membranes and an absence of pericytes and astrocyte membranes. Minimal contamination by 5'-nucleotidase, an enzyme believed exclusively localized within the plasma membranes of neuroglia, established the purity of the isolated microvessels. Enrichment of alkaline phosphatase and gamma-glutamyl transpeptidase activity in microvessel preparations supports the endothelial localization of these enzymes.
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PMID:Isolation and characterization of brain endothelial cells: morphology and enzyme activity. 610 94

Investigations were made on 253 patients. In 44 patients with peritoneal carcinosis, cell imprints and histological investigations of tissues from the changes in the peritoneum, taken during laparoscopy have been performed. In 122 out of 151 patients with neoplastically stipulated ascites (80.8 per cent) tumour cells have been found in the ascitic fluid. The false negative results represented 19.8 per cent and the false positive results--2.0 per cent. In all cell imprints from peritoneal tissues tumour cells have been detected even when these were absent in the ascitic fluid. In 2 out of 49 patients (4 per cent) the histological investigation of bioptic material from the peritoneum showed no neoplastic changes. The activity of gamma-glutamyltransferase and alkaline phosphatase in the ascitic fluid of patients with carcinosis was higher than in the remaining patients, whilst the 5'-nucleotidase did not show particular deviations. The cytologic method was well tolerated by the patients and showed higher specificity, sensitiveness, simplicity and realization and in 80.8 per cent solved the diagnostic problems and made useless the application of other labour-consuming, burdensome and more expensive methods of investigation.
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PMID:[Advantages of cytodiagnostics in ascites (author's transl)]. 612 Jun 88

To study the effect of chronic alcohol administration on the activities of liver plasma membrane enzymes such as gamma-glutamyltransferase, alkaline phosphatase and 5'-nucleotidase, female rats were pair-fed for 6 weeks nutritionally adequate liquid diets containing either ethanol or isocaloric carbohydrates as controls. Compared to the control diet, chronic alcohol administration resulted in a significant enhancement of serum activities of gamma-glutamyltransferase, alkaline phosphatase and 5'-nucleotidase by 91% (P less than 0.005), 80% (P less than 0.001) and 65% (P less than 0.01), respectively. Concomitantly, chronic alcohol intake led to a striking increase of gamma-glutamyltransferase activities in liver homogenates by 68% (P less than 0.001), in liver plasma membranes rich in bile canaliculi by 80% (P less than 0.025), and in liver plasma membranes free of bile canaliculi by 24% (P less than 0.02). However, chronic ethanol consumption had no effect on alkaline phosphatase activities in liver homogenates and liver plasma membranes but significantly suppressed 5'-nucleotidase activities. These results therefore show that chronic intake of ethanol increases serum activities of enzymes originating from liver plasma membranes but has different effects on the enzyme activity in liver plasma membranes itself, suggesting that the alcohol-mediated increase of serum activities of various enzymes originating from liver plasma membranes might be due to different mechanisms.
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PMID:Effect of chronic alcohol consumption on the activities of liver plasma membrane enzymes: gamma-glutamyltransferase, alkaline phosphatase and 5'-nucleotidase. 612 53


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