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)

An increase of thymidine kinase [EC 2.7.1.21] activity and decrease of 5'-nucleotidase [EC 3.1.3.5] activity for dTMP were found during hormonal regeneration of the seminal vesicles by daily or single administration of testosterone propionate into mice castrated 2 weeks previously. Actinomycin D injected on day 0 of testosterone treatment completely inhibited both the increase of thymidine kinase and the decrease of 5'-nucleotidase. When injected on day 2, actinomycin D decreased thymidine kinase activity below the control level and 5'nucleotidase activity was not restored to the normal level. The activity of 5'-nucelotidase in a mixed sample, in which seminal vesicles of castrated mice and those of testosterone-treated mice were homogenized together, was intermediate between the activities determined separately. This indicates the absence of any inhibitor of 5'nucleotidase in the regenerating vesicles. Changes in total activity of 5'nucleotidase and total protein content in extracts during various treatments showed that the decrease in specific activity of 5'-nucleotidase in the first 2 days of testosterone treatment was not due to inhibition of enzyme activity but to dilution of the enzyme with other proteins which increased in content more rapidly than 5'-nucleotidase.
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PMID:Changes in enzyme activities of thymidine kinase and 5'-nucleotidase for dTMP during hormonal regeneration of seminal vesicles of mice. 7 66

1. Extracts of several plant species contained nucleoside-AMP phosphotransferase activity. The ratio of activity with thymidine to that with uridine as nucleoside substrate was essentially constant, both between species and throughout plant development. Evidence is presented that the total thymidine-AMP phosphotransferase activity of the leaves of Asplenium nidus (bird's-nest fern) and of Helianthus tuberosus (Jerusalem artichoke) increases during maturation. 2. Thymidine-AMP phosphotransferase was purified 22-fold from a very rich source of this activity, extracts of A. nidus. 3. A broad specificity towards both nucleoside and nucleoside 5'-monophosphate substrates is displayed by this preparation, and the evidence suggests that all could be due to a single enzyme. 4. Nucleosides that act as substrates will also inhibit phosphotransfer to other nucleosides, with Ki values close to the corresponding Km values found when utilized as substrates. 5. Ca2+-activated ATP phosphohydrolase was separated from the phosphotransferase by differential complexing to Blue Dextran in the presence of urea, whereas an AMP phosphohydrolase activity was closely associated with thymidine-AMP phosphotransferase through all separation techniques used. 6. Metal ions did not activate either of the latter two activities, and 1,10-phenanthroline was found to inhibit the phosphotransferase. 7. Km values for AMP for the respective activities were 0.11 mM (thymidine phosphotransferase) and 0.20 mM (AMP phosphohydrolase) and for thymidine (phosphotransferase only) 0.88 mM. 8. 3':5'-Cyclic AMP was found to inhibit both phosphotransferase and AMP phosphohydrolase activities, with Ki values of 0.056 mM and 0.15 mM respectively. It is suggested that this inhibitor would be of value in revealing the existence of thymidine kinase in plant extracts with high thymidine phosphotransferase activity.
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PMID:Thymidine phosphotransferase and nucleotide phosphohydrolase of the fern Asplenium nidus. General properties and inhibition by adenosine 3':5'-cyclic monophosphate. 18 31

Damage to the lung may be caused by chemicals that gain access to the alveolar zone by inhalation or via the pulmonary circulation. Several agents toxic to the lung have recently been found to bind covalently to pulmonary macromolecules or to disrupt certain metabolic reactions. However, it has also been observed that extensive chemical lung injury is not necessarily preceded by a depression of pulmonary metabolic reactions. One possible explanation for this might be that biochemical changes due to cell death are often masked and/or compensated for by changes associated with lung tissue repair. Substantial cell proliferation as a response to toxic lung damage is a common phenomenon in lung pathology. This makes it necessary to develop models that permit analysis of the biochemical events triggering and accompanying cell growth in lung. We have recently examined some aspects of cell proliferation in mouse lung. Intraperitoneal injection of the antioxidant butylated hydroxytoluene (BHT) produces within 3-5 days extensive hypertrophy, hyperplasia, and general disorganization of the cellular components of the lung. Total lung weight and total DNA per lung almost double within this time and are accompanied by proportional increases in protein and lipids. RNA accumulates at a faster rate than DNA. The changes in lung composition are accompanied by dose-dependent increases in the in vivo incorporation of thymidine into DNA and of leucine into protein. The activities of several enzymes (thymidine kinase, DNA polymerase, uridine kinase, glucose-6-phosphate dehydrogenase, and 5'-nucleotidase) increase substantially after BHT. Administration of BHT to mice seems to offer a convenient tool to study cell growth in the lungs of mice.
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PMID:Biochemical pathology of lung damage produced by chemicals. 124 36

Male mice of 7 different strains were injected i.p. with 400 mg/kg of butylated hydroxytoluene (BHT). 2 and 4 days later, the incorporation of thymidine into pulmonary DNA was significantly increased in all treated animals and this was accompanied by an increase in lung weight and pulmonary DNA. Thymidine kinase activity and DNA polymerase activity were enhanced in the lungs of BHT-treated animals and maximum activity of these enzymes appeared to precede maximum thymidine incorporation by 24 h. 3 days after BHT a good correlation was found between administered dose and thymidine kinase activity. Measuring the activity of this enzyme might serve as a convenient biochemical marker to follow and to quantitate BHT-produced cell proliferation in lung. The concentrations of cyclic AMP and the activity of adenylate cyclase were not altered by BHT on days 1-9 after administration. BHT produced also some dose-dependent, time-dependent increases in the activities of pulmonary 5'-nucleotidase and glucose-6-phosphate dehydrogenase (G6PDH), but had little effect on isocitric dehydrogenase (ICDH), pyruvate kinase (PK) and lactic dehydrogenase (LDH).
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PMID:Biochemical paramters of BHT-induced cell growth in mouse lung. 124 55

Chronic exposure of H9 cells to 25 microM zidovudine (H9-AZT cells) causes a 2- to 3-fold increase in thymidine kinase (TK) activity (Agarwal RP, Int J Purines Pyrimidine Res, in press). The present study compared thymidine (TdR) and AZT anabolism in H9 and H9-AZT cells. After a 3.5-hr incubation with 10 microM TdR or AZT, the total intracellular accumulations of AZT (48.7 microM in H9 cells and 32.8 microM in H9-AZT cells) were 46.4% of TdR accumulation. Other major differences between TdR and AZT anabolism were: (i) the majority of TdR (84-87%) was incorporated into DNA compared to less than 1% of AZT; and (ii) whereas distribution of TdR in the nucleotides was TTP greater than TMP greater than TDP, zidovudine distributed was AZT-MP much greater than AZT-TP much greater than AZT-DP. Because of the poor substrate activity of AZT-MP for thymidylate kinase (TMP-kinase), most of the AZT (95-98%) remained as AZT-MP. TMP-kinase activities with TMP as substrate were 47.6 +/- 20.3 and 91.4 +/- 28.8 pmol/mg protein/min in H9 and H9-AZT cells, respectively. 5'-Nucleotidase activities with TMP as substrate were 428.9 +/- 37.8 and 255.9 +/- 28.7 pmol/mg protein/min in H9 and H9-AZT cells, respectively. Activities of these enzymes with AZT-MP as a substrate were very low. Despite an increase in TK and TMP-kinase, and a decrease in 5'-nucleotidase activities, the total intracellular accumulations of TdR and AZT were reduced significantly (P less than 0.05) to 67.5% in H9-AZT cells. Thymidine transport (0.66 to 0.68 pmol/sec/10(6) cells) was similar in both the cell lines. The severe reductions of TdR salvage caused by chronic exposure of cells to AZT, if it occurs in AIDS patients on AZT chemotherapy, may explain some of the long-term clinical toxicities of the drug.
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PMID:Thymidine and zidovudine metabolism in chronically zidovudine-exposed cells in vitro. 186 45

Blood serum activities of thymidine kinase, thymidine phosphorylase, adenosine deaminase, and 5'-nucleotidase were measured in normal women, women suffering from mastopathies and mammary carcinomas, aged 36 to 70. Blood serum activities of the studied enzymes in mammary carcinoma patients differed from these values in healthy women and those suffering from mastopathies; these differences were age-associated. Measurements of the time course of enzymic activities before and in the course of chemotherapy may be employed as a biochemical test to monitor therapy efficacy.
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PMID:[Use of the study of DNA metabolism enzyme activities as a test system in the treatment of breast cancer]. 205 30

Age-related changes in the activity of thymidine- and adenosine-metabolizing enzymes were studied in healthy females and those with breast cancer aged 46-70 years. A significant increase in activity of thymidine kinase, adenosine deaminase and 5'-nucleotidase and a decrease in that of thymidine phosphorylase were registered in blood serum of breast cancer patients of all age brackets. Adenosine deaminase activity in blood serum and lymphocytes of breast cancer patients was found to significantly change after surgery. A direct correlation was established between pretreatment thymidine phosphorylase activity and histological type of tumor, on the one hand and results of chemotherapy, on the other. The applicability of enzyme level assay for evaluating response to pre- and postoperative medication was studied.
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PMID:[Activity of the enzymes of DNA metabolism in the blood of patients with breast cancer]. 215 96

Activities of thymidine kinase, thymidine phosphorylase, adenosine deaminase and 5'-nucleotidase of AMP were studied in blood serum and lymphocytes of healthy women, patients with mastopathy and with mammary gland cancer of 23-70 years old. Age-dependent alterations in the enzymatic activity were detected in blood serum of healthy women. Activity of thymidine kinase was increased simultaneously with a decrease in thymidine phosphorylase activity in 36-70 years old oncological patients, while adenosine deaminase activity was increased in patients with mastopathy and with mammary gland cancer of all the age groups. Dynamics of the enzymatic activity studied before and during chemotherapeutic treatment may be used as one of biochemical tests for evaluation of the therapy efficiency in oncological patients.
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PMID:[Age-dependent characteristics of metabolism of DNA precursors in healthy women, patients with mastopathy and breast cancer]. 225 96

The activity of thymidine kinase, thymidine phosphorylase, adenosine deaminase, AMP 5'-nucleotidase was assessed in the serum of healthy females, patients with mastopathia cystica and those with stage IIIB breast cancer. The females age ranged from 23 to 70 years. The activity of the enzymes had significant differences in cancer patients. Minimal thymidine phosphorylase activity was found to suggest fibrous cancer. Changes in the enzymes levels in cancer patients on combined treatment may serve a biochemical test indicating the efficacy of the chemotherapy conducted.
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PMID:[Use of enzyme test in chemotherapy of patients with cancer of the breast]. 228 21

The activity of metabolic enzymes, adenosine and thymidine, has been studied in the blood serum and lymphocytes of healthy people and oncological patients aged 23-80. An increase in the activity of thymidine kinase (EC 2.7.1.2), an enzyme of thymidine biosynthesis, was observed in the blood serum of oncological patients against a background of a sharp decrease in the activity of thymidine phosphorylase (EC 2.4.2.4), a catabolic enzyme. The revealed enzymic shifts have been observed in breast cancer patients after 36, in patients with the stomach cancer--after 46. It is found that an increase in the activity of adenosine deaminase (EC 3.5.4.4) and 5-nucleotidase of AMP (EC 3.1.3.5) in the blood serum of oncological patients is accompanied by a sharp decrease in the activity of these enzymes in lymphocytes.
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PMID:[Activity of adenosine and thymidine metabolism enzymes in the blood of cancer patients of various ages]. 233 24


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