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

Various enzymes in the semen of men were examined to see if any could be related to measures of fertility. Fumarase activity was highly correlated with sperm number and percentage motility. Diamine oxidase activity was higher in samples with sperm counts of less than 20 X 10(6)/ml and aperm motility of less than 20%. Monoamine oxidase, adenine deaminase and prostaglandin dehydrogenase were undetectable in significant amounts in all samples, while peroxidase and adenosine deaminase were not correlated with sperm count and motility. It is suggested that the simple spectrophotometric assays for fumarase and diamine oxidase could form the basis of a routine assessment of human semen samples for estimation of male infertility.
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PMID:The development of a qualitative assay for male infertility from a study of enzymes in human semen. 41 Sep 26

The distribution of adenosine deaminase and adenosine deaminase complexing protein in rabbit heart has been compared using immunohistochemical staining procedures. Sections (4-5 microns) of tissue fixed in Clarke's solution or paraformaldehyde and embedded in paraffin were stained by the peroxidase anti-peroxidase method for adenosine deaminase or complexing protein, using affinity purified antibodies. Staining for adenosine deaminase and complexing protein was observed in the central myocardium of all heart chambers. Adenosine deaminase was detected in endothelial cells of blood vessels and adjacent pericytes. The nuclei of arteries stained heavily for adenosine deaminase, whereas those of venules and small veins, although positive, stained much more lightly. The cytoplasm of blood vessel endothelial cells and smooth muscle cells of the tunica media were also weakly positive for adenosine deaminase. Endothelial cells of the endocardium and epicardium did not stain. Randomly distributed mononuclear inflammatory cells and interstitial connective tissue fibroblasts were also negative for adenosine deaminase. These results raise the possibility that endothelial cells containing adenosine deaminase could serve as a metabolic barrier preventing the free exchange of plasma and interstitial adenosine. Positive staining for complexing protein was restricted to blood vessel endothelial cells, especially cytoplasmic processes. Colocalization experiments carried out with biotinylated primary antibodies indicate that some vessels are positive for both adenosine deaminase and complexing protein. This is the first experimental evidence of possible in situ association of adenosine deaminase and complexing protein.
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PMID:Localization of adenosine deaminase and adenosine deaminase complexing protein in rabbit heart. Implications for adenosine metabolism. 168 16

Acetylcholine and ATP are costored and coreleased during synaptic activity at the electric organ of Torpedo. It has been suggested that released ATP is converted to adenosine at the synaptic cleft, and in turn this nucleoside would depress the evoked release of acetylcholine. In the present communication we have used a chemiluminescent reaction that let us to monitor continuously the presence of adenosine in this preparation. The chemiluminescent reaction is based on the conversion of adenosine into uric acid and H2O2 by adenosine deaminase, nucleoside phosphorylase, and xanthine oxidase enzymes. The hydrogen peroxide has been detected by peroxidase-luminol mixture. The reaction has a sensitivity on the picomol range and discerned between Adenosine, AMP, ADP, and ATP. We have developed this technique in the hope of understanding whether adenosine is released during synaptic activity or it comes from the released ATP. We have studied the release or formation of adenosine in fragments of the electric organ and in isolated cholinergic nerve terminals obtained from it. In both conditions we have followed the effect of potassium stimulation upon the detection of adenosine. Potassium stimulation increased the extracellular adenosine either in slices or the synaptosomal fraction of Torpedo electric organ. The presence of alpha, beta-methylene ADP, an inhibitor of 5'-nucleotidase, inhibits the detection of adenosine, suggesting that extracellular adenosine is a consequence of ectocellular dephosphorylation of released ATP.
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PMID:The release of adenosine at the electric organ of Torpedo. A study using a continuous chemiluminescent method. 232 27

Specific sensitive rabbit antisera directed against the adenosine derivative laevulinic acid (O2',3'-adenosine acetal), which are capable of detecting as little as 1 pmol of adenosine by radioimmunoassay and which require more than 1000- to 40,000-fold greater concentrations of adenine nucleotides to displace adenosine binding to antisera, have been developed. These antisera were employed to localize adenosine immunoreactivity throughout the rat CNS using the peroxidase-antiperoxidase (PAP) complex and avidin-biotin-peroxidase complex (ABC) immunocytochemical techniques. Intense staining for adenosine immunoreactivity was localized to the cytoplasm of perikarya and fibers in neuronal cell groups of discrete rat brain regions. Areas containing highest levels of immunoreactivity included the pyramidal cells of the hippocampus, the granule cells of the dentate gyrus, subnuclei of the thalamus, amygdala, and hypothalamus, the primary olfactory cortex, and many motor and sensory nuclei of the brain stem and spinal cord. High levels also occurred in certain layers of the cerebral cortex, the caudate-putamen, the septal nuclei, and the Purkinje cell layer of the cerebellum. Varying the extent of tissue hypoxia altered only the levels of endogenous immunoreactive adenosine without changing the pattern of distribution of the immunoreactivity. Staining was abolished by immunoabsorption and by pretreatment of tissue sections with adenosine deaminase. The localization of adenosine to discrete neuronal groups in the brain supports the possibility of a neurotransmitter or neuromodulatory role for adenosine.
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PMID:Adenosine-containing neurons in the brain localized by immunocytochemistry. 242 24

We investigated the subcellular location of adenosine deaminase-complexing protein in the proximal renal tubules of rabbit kidney and its interaction with intravenously infused monomeric calf adenosine deaminase. Cortical tissue from non-infused animals, stained in suspension by the peroxidase-antiperoxidase method for complexing protein and embedded in resin, was examined by transmission electron microscopy. Positive staining indicated the presence of complexing protein on the surface of microvilli in the proximal tubules. Sections (1 micron) of resin-embedded cortex from infused rabbits, stained first for complexing protein and then for adenosine deaminase, were examined by light microscopy. After staining for complexing protein by indirect immunofluorescence, the sections were photographed and then immersed in buffer containing 6 M guanidine hydrochloride plus 2-mercaptoethanol for 3 hr at 60 degrees C to remove bound antibodies. The sections were then stained by the peroxidase-antiperoxidase method for infused enzyme. Vesicle-like apical structures, the basal membrane area and, as previously reported, the brush border of proximal tubule cells were positive for complexing protein. Vesicle-like structures and brush borders positive for complexing protein were also stained for adenosine deaminase. The basal membrane area did not stain. These results support the hypothesis that complexing protein can act as a receptor for adenosine deaminase.
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PMID:Evidence for receptor-mediated uptake of adenosine deaminase in rabbit kidney. 246 11

The distribution and morphology of adenosine deaminase, substance P, leucine-enkephalin, corticotropin-releasing factor, and calcitonin gene-related peptidelike immunoreactive cells and fibers throughout the superior colliculus of the rat were examined by means of the unlabelled-antibody peroxidase-antiperoxidase method. Adenosine deaminase immunoreactive cells were found in the stratum opticum and lower stratum griseum superficiale; substance P immunoreactive cells were localized to the upper stratum griseum superficiale, and calcitonin gene-related peptide immunolabelled neurons were situated in deeper strata. Substance P, leucine-enkephalin, and calcitonin gene-related peptide immunoreactive fibers were distributed similarly in their lamination and in their patchlike organization. Corticotropin-releasing factor immunoreactive fibers were observed evenly throughout all the strata and were fewer in the stratum griseum superficiale. These findings suggest that, as in afferent modules and segregated efferents of the mammalian superior colliculus, the cells and fibers containing neuroactive substances and neuroactive substance-related enzymes also show a segregated and laminar distribution.
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PMID:Laminar and segregated distribution of immunoreactivities for some neuropeptides and adenosine deaminase in the superior colliculus of the rat. 246 26

Myocardial ischemia is characterized by the liberation of adenosine and by complement-mediated inflammation. We have reported that amidated C3, formed when ammonia (NH3) disrupts the thiolester bond of C3, serves as an alternative pathway convertase, generates C5b-9, and stimulates phagocytic oxidative metabolism. We investigated whether the deamination of adenosine by adenosine deaminase in hematopoietic cells might liberate sufficient ammonia to form amidated C3 and thereby trigger complement-mediated inflammation at ischemic sites. In the presence of 4 mM adenosine, NH3 production per erythrocyte (RBC) was equal to that per neutrophil (PMN) (3.3 X 10(-15) mol/cell per h). Because RBC outnumber PMN in normal blood by a thousandfold, RBC are the major source of NH3 production in the presence of adenosine. NH3 production derived only from the deamination of adenosine by the enzyme adenosine deaminase and was abolished by 0.4 microM 2'-deoxycoformycin, a specific inhibitor of adenosine deaminase. When purified human C3 was incubated with 5 X 10(8) human RBC in the presence of adenosine, disruption of the C3 thiolester increased more than twofold over that measured in C3 incubated with buffer, or in C3 incubated with RBC (P less than 0.05). The formation of amidated C3 was abolished by the preincubation of RBC with 2'-deoxycoformycin (P less than 0.001). Amidated C3 elicited statistically significant release of superoxide, myeloperoxidase, and lactoferrin from PMN. Thus, the formation of amidated C3 by RBC deamination of adenosine triggers a cascade of complement-mediated inflammatory reactions.
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PMID:The erythrocyte as instigator of inflammation. Generation of amidated C3 by erythrocyte adenosine deaminase. 278 75

A rapid enzymatic assay method for ammonia was developed by using glutamine synthetase from glutamate-producing bacteria together with pyruvate kinase, lactate dehydrogenase, and NADH. The time required for determination of 25 nmol of ammonia was 5 min with 1 unit of glutamine synthetase, as opposed to 14-30 min with 1 unit of glutamate dehydrogenases from various sources. The present method was used to determine ammonia in serum, microbiol-culture broth, and waste water. The method can be modified for spectrophotometry in the visible region by substituting pyruvate oxidase, peroxidase, and appropriate chromogens for lactate dehydrogenase and NADH. With 4-aminoantipyrine (4AA) and phenol, and with 4AA and N-ethyl-N-2-hydroxyethyl-m-toluidine as chromogens, the sensitivity of ammonia determination was 0.65 and 1.7 times that with glutamate dehydrogenase, respectively. The present method was also applicable to the continuous detection of the activity of some ammonia-forming enzymes such as guanase, adenosine deaminase, and urease and to the determination of 0.5-30 microM ATP-ADP after some modification of the mixture.
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PMID:A rapid assay method for ammonia using glutamine synthetase from glutamate-producing bacteria. 288 29

Presence of a projection containing adenosine deaminase (ADA)-like immunoreactivity from the stratum opticum (SO) to the dorsomedial portion of the lateral posterior nucleus of the thalamus (LPN) of the rat was demonstrated using a method combining retrograde tracing by horseradish peroxidase (HRP) and immunohistochemistry for ADA. In the caudal two thirds of the LPN, a clearly delimited ADA-like immunoreactive fiber plexus was located. Injection of HRP into the lateral posterior nucleus labeled many neurons in the medial portion of the SO where medium-sized neurons with ADA immunoreactivity were concentrated. Simultaneous immunostaining showed that some of the HRP-labeled neurons are ADA-positive.
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PMID:Adenosine deaminase containing fiber pathway from the superior colliculus to the lateral posterior nucleus of the rat. 291 14

The somas of primary afferent neurons in the mesencephalic nucleus of the trigeminal nerve in rat have a dense investment of axons immunoreactive for the enzyme adenosine deaminase. We previously suggested that these axons may originate from adenosine deaminase-immunoreactive neurons located in the tuberomammillary nucleus of the hypothalamus [Nagy et al. (1986) Neuroscience 17, 141-156]. Anterograde tracing and immunohistochemical techniques were used to investigate this possibility further. In addition, the appearance of adenosine-immunoreactive axons and the nature of their interactions with mesencephalic neurons was examined ultrastructurally. After injections of either Phaseolus vulgaris-leucoagglutinin or wheat germ agglutinin-horseradish peroxidase into the region of the tuberomammillary nucleus, punctate deposits of anterogradely transported tracer, detected by immunoperoxidase methods, were seen surrounding mesencephalic neurons. In sections immunostained for tracer and adenosine deaminase by double immunofluorescence, some fibres in the periaqueductal gray matter and around Mes V somas were found to be labelled for both the lectin and the enzyme. Ultrastructurally, only a single morphological class of adenosine deaminase-immunoreactive axons adjacent to, or indenting the cytoplasmic membranes of, large somas in the mesencephalic nucleus could be recognized; they were varicose and contained relatively large immunoreactive vesicles ranging in diameter from 45 to 70 nm. Occasionally, thin processes of these axons could be traced back to small adenosine deaminase-positive neuronal cell bodies located not within the tuberomammillary nucleus, but rather, within the periaqueductal gray matter. In serial ultrathin sections, membrane specializations resembling synaptic junctions were sometimes seen at points where mesencephalic somas were in contact with adenosine deaminase-immunoreactive terminals. Somas within the mesencephalic nucleus also formed such junctions with non-immunoreactive boutons which were morphologically different from, and often seen in close proximity to, those containing adenosine deaminase. These results indicate that in addition to possible afferents from the tuberomammillary nucleus, primary sensory somas within the mesencephalic nucleus are also associated with axonal processes originating from adenosine deaminase-positive neurons located within the periaqueductal gray matter. The infrequent synaptic contacts between these somas and adenosine deaminase-positive axons, despite their close anatomical arrangement, is suggestive of a diffuse endocrine or neurocrine type of axonal relationship with mesencephalic somas or with the n
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PMID:Further observations on the relationship between adenosine deaminase-containing axons and trigeminal mesencephalic neurons: an electron microscopic, immunohistochemical and anterograde tracing study. 317 93


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