Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.5.4.4 (adenosine deaminase)
 5,136 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The activity of guanine deaminase (GAH, E.C.3.5.4.3) was lower in rat cerebellum soluble and microsomal fractions than in rat brain subfractions. Adenosine deaminase (ADA, E.C.3.5.4.4) activity was released in higher proportion than guanine deaminase, purine nucleoside phosphorylase (PNP, E.C.2.1.2.4), 5'-nucleotidase (5'N, E.C.3.1.3.5), and lactate (LDH, E.C. 1.1.1.27) and malate (MDH, E.C. 1.1.1.37) dehydrogenase in press-juices of rat brain. Furthermore, nerve ending-derived fractions (synaptosomes and synaptic vesicles) showed an enrichment of adenosine deaminase and also of 5'-nucleotidase. The action of deoxycholate over the subfractions did not increase the activity of either enzyme. The contrary occurred with the remaining enzymes studied. Thus, it is possible that one set of enzymes are located on the surface of the particulate vesicles, whereas another set are located inside these vesicles, suggesting a compartmentation of purine catabolic enzymes in different areas of the central nervous system.
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PMID:Heterogeneous localization of some purine enzymes in subcellular fractions of rat brain and cerebellum. 301 Jan 50

A correlation between reactions of the sympathoadrenal system and the activity of adenosine transformation enzymes in lymphocytes is demonstrated in the dynamics of metastatic Lewis carcinoma development in C57Bl mice. In the period when metastases arise a decrease in the adenosine deaminase activity in lymphoid cells of the thymus and spleen is accompanied by drop in the content of DOPA, noradrenalin and adrenalin in adrenals. At the late stages of the tumour process a decrease in the amount of these compounds in adrenals is accompanied by the diminution of the adenosine deaminase activity and by an increase in the 5'-nucleotidase activity in the thymus. Contrary changes are observed in spleen lymphocytes. The revealed disturbances may stimulate to a considerable extent the appearance and growth of metastases.
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PMID:[Enzymes of adenosine metabolism in lymphocytes and the functional state of the sympatho-adrenal system in tumor processes]. 301 May 22

Differences in activities of the purine degradative enzymes, adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP), and 5'-nucleotidase (5'NT), have been observed among different classes of lymphoid malignancies. Recent studies have shown that hairy cell leukemia (HCL) may respond to treatment with the ADA inhibitor, 2-deoxycoformycin. This study demonstrates that the cells of HCL have significantly lower levels of ADA and 5'NT (P always less than 0.01) when compared to levels in normal B- or T-lymphocytes, but have higher levels of PNP (P less than 0.001 for both comparisons). Recent studies have shown that when treated with 12-O-tetradecanoyl-phorbol-13-acetate (TPA), cells of B-cell chronic lymphatic leukemia (B-CLL) acquire phenotypic characters of HCL. The authors have therefore also investigated the changes in enzyme pattern of B-CLL after incubation with TPA B-CLL cells are characterized by low levels of ADA, PNP, and 5'-NT, but TPA caused a marked increase in PNP activity (P less than 0.001, t test for paired samples), a pattern similar to HCL. The results from biochemical studies are thus in accordance with the hypothesis that HCL cells are more mature than B-CLL cells. The special enzyme profile of HCL suggests that a PNP inhibitor might also be effective in the treatment of this disease.
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PMID:Enzymes of purine metabolism in hairy cell leukemia. 301 Dec 39

Suspensions of rat brain microsomes, synaptosomes, and synaptic vesicles were able to convert adenosine to inosine by means of adenosine deaminase. Isosbestic points of this transformation, at 222, 250 and 281 nm, remained unchanged with time-course. This fact suggests that adenosine deaminase (ADA, E.C. 3.5.4.4) is located on the surface of the vesicles whereas purine nucleoside phosphorylase (PNP, E.C. 2.1.2.4) is located inside the vesicles. Kinetic parameters of the particulate 5'-nucleotidase (5'N, E.C. 3.1.3.5) and adenosine deaminase were analogous to those of the cytosolic enzymes. These results suggest that soluble and particulate enzymes represent different pools of the same molecular species.
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PMID:Kinetics of the 5'-nucleotidase and the adenosine deaminase in subcellular fractions of rat brain. 301 60

The antimetastatic action of bacterial endotoxins (BET), E. coli 0111:B4, B in particular, as well as their influence on the adenosine deaminase and 5'-nucleotidase activity were studied in peritoneal macrophages of mice bearing lung Lewis carcinoma. BET inhibition of lung metastasis growth was found to be due to such changes in macrophage adenosine metabolism, that testifies to the rise of their functional activity. The change in the level of macrophage purine metabolism can be considered as an important evidence of the effectiveness of the drugs capable to inhibit the metastasis growth.
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PMID:[Antimetastatic action of bacterial endotoxins and changes in the activity of the enzymes of purine metabolism in macrophages]. 301 30

Activities of key enzymes of purine metabolism [adenosine deaminase (AD); purine nucleoside phosphorylase (PNP); 5'-nucleotidase] were studied; changes in DNA content, nucleus ploidity in thymocytes, T- and B-lymphocytes in the C3HA mouse spleen during solid 22 hepatoma growth and after the immunization were monitored. Immunological properties of lymphocytes were also investigated measuring antibody formation and the reaction of blasttransformation in response to phytohemagglutinin, concanavalin A and lipopolysaccharide. Within the first 48 hrs after the tumor implantation and immunization certain nonspecific biochemical mechanisms of lymphocytes activation (elevated AD activity, decreased activity of 5'-nucleotidase, augmented intracellular DNA levels, polyploidity) were revealed. As the solid 22 hepatoma reached the maximum growth rate specific alterations in the activities of the purine metabolism key enzymes were observed reflecting the response of thymus and spleen lymphocytes to the presence of the malignant tumor.
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PMID:[Biochemical and functional characteristics of thymus and spleen lymphocytes in C3HA mice during the growth of hepatoma 22 and after immunization with sheep erythrocytes]. 302 Jul 91

The 5'-nucleotidase and adenosine deaminase activities were determined for tissue extracts of up to 10 defined regions of the normal dog heart. The specific activity of 5'-nucleotidase was very significantly higher in atrial than in ventricular myocardium (4 X) and was also higher in right than in left sites of the heart (2 X). The reason for the markedly higher specific activity in atrial muscle is not clear and appears paradoxical relative to adenine nucleotide content and pattern of ATP decay during oxygen deprivation. In contrast to 5'-nucleotidase activity the total adenosine deaminase activity was found to be similar in all sampling sites examined.
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PMID:Relative activities of 5'-nucleotidase and adenosine deaminase in atrial and ventricular myocardium--the enzyme paradox. 302 11

Three catabolic enzymes, 5'-nucleotidase (5'NT), adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP) and one anabolic enzyme, myokinase (MK) involved in adenine nucleotide (AN) metabolism were studied in myocardium from 4 to 105 day old rats. The specific enzyme activities (nmoles/min/mg protein) at day 4 were 35.3 for 5'NT, 28.4 for ADA, 43.3 for PNP, and 5 X 10(3) for MK. At day 7, 5'NT, activities rose to 450%; PNP and ADA 150%; and MK 120%; of the day 4 level. The activities of the three catabolic enzymes were elevated for one or two weeks then declined rapidly. By day 34, they were slightly above the adult values. MK activity displayed a different time course. It continued to increase slowly with age after the initial surge. Compared to the adult heart, the total activities of these catabolic enzymes in the one- to three-week-old heart were 30% to 220% higher. This transient elevation in AN catabolic enzyme activities may be related to active DNA synthesis and cell proliferation occurred in the rat myocardium during the same period.
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PMID:Postnatal changes in enzyme activities of rat myocardial adenine nucleotide catabolic pathway. 302 44

Surgical operation of metastatic Lewis carcinoma, carried out in male mice of C57B1 strain, which stimulated distinctly the metastases spreading, was accompanied by phase impairments in activities of adenosine deaminase and 5'-nucleotidase in immunocompetent cells correlating with neurochemical stressory reactions. Thus, excessive stressory alterations in activity of symptoadrenal and hypothalamic mediatory systems appear to be among the factors responsible for inhibition of metabolism in lymphoid cells and for stimulation of metastatic spreading.
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PMID:[Adenosine metabolism in lymphocytes and neurochemical stressor reactions in mice with metastatic Lewis carcinoma after surgical removal of the tumor]. 302 90

Activities of adenylate-degrading enzymes in muscles of vertebrates and invertebrates were determined. Mammalian and fish muscles showed a markedly higher activity of AMP deaminase with a lower level of adenosine deaminase and 5'-nucleotidase. Cephalopods showed an active adenosine deaminase and a 5'-nucleotidase which preferred AMP as the substrate. Negligible deamination of AMP and adenosine and little phosphohydrolase activity toward AMP and IMP were observed in the shellfish muscles. Adenine nucleotides can be degraded to form IMP via the AMP deaminase reaction in vertebrate muscles, while dephosphorylation of AMP to adenosine, which is then converted to inosine, appears to proceed in cephalopods. Adenylates can be hardly degraded in shellfish muscles.
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PMID:Activities of adenylate-degrading enzymes in muscles from vertebrates and invertebrates. 303 Jun 25


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