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)

A bovine calf lens epithelial cell line (CLE-1) that synthesizes crystallin has been established in culture and some of its transport properties have been characterized using both cells and membrane vesicles derived from them. The membrane vesicles fractionate with high recovery of plasma membrane markers, showing a 40-fold purification of 5'-AMPase and a 20-fold decrease in the specific activity of the mitochondrial marker enzyme succinic dehydrogenase relative to a cell homogenate. Transport sites demonstrated higher specific activity than has been seen in vesicles from cell lines studied previously. The uptake of alpha-amino isobutyric acid (AIB) (an alanine analog) by CLE-1 cells is stimulated four- to fivefold by Na+ and exhibits a Km of 5.4 mM with a Vmax of 50 pmoles/min.microgram of cell protein. The uptake of leucine was not Na+ stimulatable. The uptake of AIB by the cells was reduced by 43% at confluence. Thus, the cell density dependent behavior of the uptake of the alanine amino acid family in CLE-1 is similar to that of various fibroblast cells. The Na+ caused a threefold stimulation of AIB uptake in the membrane vesicles, while vesicular uptake of leucine was unaffected by Na+. The uptake of adenine, guanine, uridine, and guanosine was also tested in these vesicles. The substrates were rapidly accumulated, came to a steady state distribution within 1-2 minutes, and were recovered as the unaltered compounds after uptake.
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PMID:Nutrient transport in a bovine lens epithelial cell line. 725 81

Adult rat testis homogenates were fractionated by differential centrifugation followed by two discontinuous gradient centrifugation steps under identical conditions except for the absence of digitonin in the first gradient and the presence of 0.03% digitonin in the second gradient. The first gradient centrifugation yielded a membrane fraction enriched 28.8-fold in 5'-nucleotidase, 21.5-fold in UDP-Gal:GlcNAc galactosyltransferase and 18.6-fold in UDP-GlcNAc:alpha-D-mannoside N-acetylglucosaminyltransferase. Repeat centrifugation of this membrane fraction in the denser level of the gradient; this material was enriched 32.1-fold in 5'-nucleotidase but only 1.9-fold in galactosyltransferase and 8.4-fold in N-acetylglucosaminyltransferase. The plasma membrane fraction was shown to be free of glucose-6-phosphatase, succinate dehydrogenase, beta-N-acetylglucosaminidase, DNA, and RNA. The fraction therefore appears to be enriched in plasma membrane but relatively free of Golgi membrane contamination, as indicated by the relatively low levels of glycosyltransferases, and of contamination by other organelles. The testicular cells which contribute plasma membrane to this fraction have not yet been definitively identified; the contribution by Sertoli cells is particularly difficult to assess since these cells have been reported to be enriched in 5'-nucleotidase. However, sulfogalactosylalkylacylglycerol (SGG), a lipid previously shown to be present primarily in primary spermatocytes, spermatids, and spermatozoa, was enriched 33.1-fold in the plasma membrane fraction; this finding as well as experiments with [35S]sulfate-labeled sulfogalactosylalkylacylglycerol at various times after injection of radioactive label have indicated that both spermatocytes and spermatids were contributing SGG-rich membrane material to our plasma membrane preparation. This membrane material is most probably derived from the plasma membranes of the spermatocytes and spermatids.
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PMID:Enrichment of sulfogalactosylalkylacylglycerol in a plasma membrane fraction from adult rat testis. 745 82

The effect of carrot extract on carbon tetrachloride (CCl4)-induced acute liver damage was evaluated. The increased serum enzyme levels (viz., glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, lactate dehydrogenase, alkaline phosphatase, sorbitol and glutamate dehydrogenase) by CCl4-induction were significantly lowered due to pretreatment with the extract. The extract also decreased the elevated serum bilirubin and urea content due to CCl4 administration. Increased activities of hepatic 5'-nucleotidase, acid phosphatase, acid ribonuclease and decreased levels of succinic dehydrogenase, glucose-6-phosphatase and cytochrome P-450 produced by CCl4 were reversed by the extract in a dose-responsive way. Results of this study revealed that carrot could afford a significant protective action in the alleviation of CCl4-induced hepatocellular injury.
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PMID:Hepatoprotective activity of carrot (Daucus carota L.) against carbon tetrachloride intoxication in mouse liver. 750 Jun 38

Metastases in rat liver were generated experimentally by intraportal injection of colon cancer cells to investigate the effects of cancerous growth on the metabolism of surrounding liver tissue. Maximum activities (capacity) of glucose-6-phosphate dehydrogenase, phosphogluconate dehydrogenase, lactate dehydrogenase, succinate dehydrogenase, alkaline phosphatase, 5'-nucleotidase, xanthine oxidoreductase, purine nucleoside phosphorylase and adenosine triphosphatase have been determined. Two types of metastases were found, a small type surrounded by stroma and a larger type in direct contact with hepatocytes. Both types affected the adjacent tissue in a similar way suggesting that the interactions were not mediated by stroma. High capacity of the degradation pathway of extracellular purines released from dead cells of either tumours or host tissue was found in stroma and sinusoidal cells. Metastases induced both an increase in the number of Kupffer cells and proliferation of hepatocytes. The distribution pattern in the liver lobulus of most enzymes investigated did not change distinctly. However, activity of alkaline phosphatase, succinate dehydrogenase and phosphogluconate dehydrogenase was increased in hepatocytes directly surrounding metastases. These data imply that the overall metabolic zonation in liver lobuli is not dramatically disturbed by the presence of cancer cells despite the fact that various metabolic processes in liver cells are affected.
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PMID:Experimentally induced colon cancer metastases in rat liver increase the proliferation rate and capacity for purine catabolism in liver cells. 822 8

1. The subcellular distribution of the porcine adipocyte beta-adrenergic receptor was studied in fractionated adipocytes. 2. The 30,000 g pellet obtained from hypotonically lysed cells contained membrane vesicles and mitochondria; it yielded approx 200-300 fmol dihydroalprenolol-bound receptors/mg protein. 3. Activity was increased to about 1000 fmol/mg protein after isolation of a plasma membrane fraction on a Percoll gradient. 4. The 5'-nucleotidase, succinate dehydrogenase and lactate dehydrogenase activities were usually enriched in compartments different from the ligand-binding activity. 5. Activity of porcine adipocyte 5'-nucleotidase, a purported plasma membrane marker enzyme, was not distributed in the same manner as the beta-adrenergic receptor.
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PMID:Distribution of beta-adrenergic binding in fractionated porcine adipocytes. 840 53

The effect of storage of unfixed cryostat sections from rat liver for 4 h, 24 h, 3 days and 7 days at -25 degrees C was studied on the activities of lactate dehydrogenase, glucose-6-phosphate dehydrogenase, xanthine oxidoreductase, glutamate dehydrogenase, succinate dehydrogenase (all demonstrated with tetrazolium salt procedures), glucose-6-phosphatase (cerium-diaminobenzidine method), 5'-nucleotidase (lead salt method), dipeptidyl peptidase II, acid phosphatase (both simultaneous azo coupling methods), D-amino acid oxidase (cerium-diaminobenzidine-cobalt-hydrogen peroxide procedure) and catalase (diaminobenzidine method). The effect of drying of the cryostat sections at room temperature for 5 and 60 min was investigated as well. The enzyme activities were quantified by cytophotometric measurements of test and control reactions. The test minus control reaction was taken as a measure for specific enzyme activity. It was found that the activities of all the enzymes investigated, with one exception, were affected neither by storage of the cryostat sections at -25 degrees C for up to 7 days, nor by drying of the sections at room temperature for up to 60 min. The exception was xanthine oxidoreductase, whose activity was reduced by 20% after 5 min drying of sections or after 4 h storage. Therefore, only incubations for xanthine oxidoreductase activity have to be performed immediately after cutting cryostat sections, whereas for the other enzymes a considerable margin appears to exist.
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PMID:The effects of storage on the retention of enzyme activity in cryostat sections. A quantitative histochemical study on rat liver. 846 85

In the present study we have investigated whether enzyme histochemical parameters can be applied to detect early ischemic damage in rat heart after ischemia without restoration of the blood flow. Ischemia was induced by incubating heart fragments for 0, 10, 20, 30, 60, 120 and 240 min at 37 degrees C. The activity and localization of the following enzymes was studied in unfixed cryostat sections using quantitative histochemical methods: lactate dehydrogenase, creatine kinase, succinate dehydrogenase, phosphofructokinase, acid phosphatase, 5'-nucleotidase and glycogen phosphorylase. Moreover, the ultrastructure of the tissue was studied with special attention to the appearance of flocculent densities in mitochondria, which can be seen as a sign of irreversible cell damage. It was shown that glycogen phosphorylase activity in rat heart decreased after short periods (30 min) of in vitro ischemia, whereas all other enzymes studied were not decreased up to 240 min, with the exception of lactate dehydrogenase and phosphofructokinase activities which were diminished only at 240 and 120 min of ischemia, respectively. Some reaction product was found after incubating for 5'-nucleotidase activity in the absence of substrate, indicating the presence of endogenous substrate(s). This endogenous substrate disappeared from the myocytes after 20 min of ischemia. It is assumed that AMP and/or other phosphate-containing compounds play an essential role in the activation of glycogen phosphorylase. Significant reduction of glycogen phosphorylase activity is correlated with the irreversible stage of damage of myocytes as judged from the ultrastructure.
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PMID:Histochemical detection of glycogen phosphorylase activity as parameter for early ischemic damage in rat heart. 850 31

The activities of Na+, K(+)-ATPase and 5'-nucleotidase of the plasma membranes, Ca++, Mg(++)-ATPase of the sarcoplasmic reticulum, mitochondrial cytochrome C-oxidase and succinate dehydrogenase were investigated in the brain, liver and gastrocnemius muscle of Wistar rats at various terms of adaptation to hypoxic hypobaric intermittent hypoxia. An increase in the activity of Na+, K(+)-ATPase and mitochondrial enzymes (mostly in the liver) as well as in the activity of Ca++, Mg(++)-ATPase in the skeletal muscle beginning from 14 days of adaptation have been shown. Starting with the same term the authors have registered the less marked changes of the enzymic markers of cell membranes in adapted rats under additional acute and severe hypoxic test when compared to unadapted animals. Possible changes in the regulation of membrane-bound enzyme activity during the process of adaptation to hypoxic hypoxia have been discussed.
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PMID:[Enzymatic markers of cell membranes in rats during adaptation to hypoxic hypoxia]. 946 44

The mechanisms and myocardial alterations associated with NO-deficient hypertension are still far from clear. The aim of the present study was to focus on the enzyme histochemical and subcellular changes in the heart of L-NAME treated rats, as well as to examine the influence of captopril treatment. Wistar rats were administered either L-NAME (40 mg/kg/day) alone or together with captopril (100 mg/kg/day) for a period of 4 weeks. A significant increase of blood pressure confirmed the reliability of the model. The results showed that long-lasting L-NAME administration was accompanied by a decrease of endothelial NO-synthase activity and by a significant local decrease of the following enzyme activities: capillary-related alkaline phosphatase, 5'-nucleotidase and ATPase (but not dipeptidyl peptidase IV) and cardiomyocyte-related glycogen phosphorylase, succinic dehydrogenase, beta-hydroxybutyrate dehydrogenase and ATPases. No activity of these enzymes was found in the scar, whereas a marked increase of alkaline phosphatase and dipeptidyl peptidase IV activities was found in the foci of fibrotization. Histochemical changes correlated with subcellular changes, which were characterized by 1) apparent fibroblast activation associated with interstitial/perivascular fibrosis, 2) heterogeneous population of the normal, hypertrophic and injured cardiomyocytes, 3) enhancement of the atrial granules and their translocation into the sarcolemma, and 4) impairment of capillaries as well as by induction of angiogenesis. Similar alterations were also found in the heart of captopril co-treated rats, despite of the significant suppression of blood pressure. The results indicate that NO-deficient hypertension is accompanied by metabolic disturbances and ultrastructural alterations of the heart and these changes are probably not induced by the renin-angiotension system only.
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PMID:Chronic disturbances in NO production results in histochemical and subcellular alterations of the rat heart. 1080 8

Administration of aflatoxin B1 to rats (2 mg/kg intraperitoneally) caused significant increase in the activities of gamma-glutamyl transpeptidase, 5'-nucleotidase, acid phosphatase, acid ribonuclease as well as content of lipid peroxides in liver after six weeks. However, the activities of succinate dehydrogenase, glucose-6-phosphatase, catalase, superoxide dismutase, glutathione-S-transferase, glutathione peroxidase and glutathione reductase in liver were decreased. The levels of glycogen and reduced glutathione were also decreased. There were significant elevations in the levels of serum transaminases, phosphatases (acid and alkaline), dehydrogenases (sorbitol, lactate and glutamate) and bilirubin following aflatoxin B1 administration. Picroliv (25 mg/kg/day orally for six weeks), an iridoid glycoside isolated from the roots and rhizomes of Picrorhiza kurroa, significantly prevented the biochemical changes induced by aflatoxin B1.
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PMID:Biochemical changes induced in liver and serum of aflatoxin B1-treated male wistar rats: preventive effect of picroliv. 1116 62


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