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 distribution of enzymes, viz., alkaline phosphatase, acid phosphatase, adenosine monophosphatase and adenosine triphosphatase was studied by histochemical methods in the accessory respiratory organs of two fresh-water fishes (Clarius batrachus and Heteropneustes fossilis). Enzymes have been used as markers to differentiate between functional and non-functional cells of the dendritic organ of Clarius and of the air chamber of Heteropneustes. The variations in the enzyme activities have been correlated with the functional capacity of each respiratory organ. It is attempted to understand the physiological role of these enzymes in the process of aerial breathing.
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PMID:Phosphatases in the accessory respiratory organs of two fresh-water fishes. 20 22

1. Cortisol treatment of rabbit foetuses in utero at 24 days gestation produced a significant decrease in the lung-weight to body-weight ratio compared with littermate controls by day 26. Histological examination revealed that the alveoli of the treated lungs were more open, the walls were thinner and the osmiophilic bodies were more numerous. 2. Cortisol treatment as described above produced significant increases (P<0.05) in the rates of incorporation of [(14)C]choline into phosphatidylcholine and of [(14)C]ethanolamine into phosphatidylethanolamine in vitro compared with littermate controls. This indicates that glucocorticoids produce an overall increase in phospholipid metabolism rather than a specific increase in phosphatidylcholine production. 3. The addition of 1,2-diacyl-sn-glycerols from egg phosphatidylcholine produced a 10-fold increase in the activity of choline phosphotransferase and a 3-fold increase in the activity of ethanolamine phosphotransferase in rabbit lung homogenates. The addition of 1,2-dipalmitoyl-sn-glycerol did not affect these activities. These results demonstrate that in the presence of exogenous 1,2-dipalmitoyl-sn-glycerol, the activities of these enzymes are dependent on the presence of endogenous 1,2-diacylglycerols. 4. Cortisol administration had no significant effect on the activity of choline phosphotransferase or ethanolamine phosphotransferase with endogenous or exogenously added diacylglycerols. The activities of other endoplasmic-reticulum enzymes (sn-glycerol 3-phosphate phosphatidyltransferase, sn-glycerol 3-phosphate acyltransferase and NADPH-cytochrome c reductase) were not significantly altered by the hormone administration. Oestrone sulphate sulphohydrolase activity was significantly decreased (P<0.05) by cortisol injection, but this effect varied with the foetuses from different does. 5. Cortisol administration had no effect on the activities of mitochondrial (monoamine oxidase, succinate dehydrogenase), plasma-membrane (5'-nucleotidase) or lysosomal (acid phosphatase, N-acetyl-beta-d-glucosaminidase) enzymes. The activity of membrane-associated phosphatidate phosphohydrolase, an enzyme associated with the osmiophilic granules of the type-II alveolar cells, was increased in the lungs of treated foetuses, but the difference was not significant (0.10>P>0.05).
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PMID:Cortisol induction of pulmonary maturation in the rabbit foetus. Its effects on enzymes related to phospholipid biosynthesis and on marker enzymes for subcellular organelles. 20 47

Although the preparation of rat liver Golgi apparatus isolated by our method contains appreciable activities of NADH- and NADPH-cytochrome c reductases and glucose-6-phosphatase, these enzymes as well as thiamine pyrophosphatase of the extensively fragmented Golgi fraction are partitioned in aqueous polymer two-phase systems quite differently from those associated with microsomes. Similarly, the partition patterns of acid phosphatase and 5'-nucleotidase of the Golgi fragments differ from those of homogenized lysosomes and plasma membrane, respectively. It is concluded that most, if not all, of these marker enzymes in the Golgi fraction cannot be ascribed to contamination by the non-Golgi organelles. In sucrose density gradient centrifugation the NADH- and NADPH-cytochrome c reductase activities of the Golgi fraction behave identically with galactosyltransferase but differently from the reductase activities of microsomes, again indicating that the reductases are inherently associated with the Golgi apparatus. NADPH-cytochrome c reductase of the Golgi preparation is immunologically identical with that of microsomes. The marker enzymes mentioned above and galactosyltransferase behave differently from one another when the Golgi fragments are subjected to partitioning in aqueous polymer two-phase systems, suggesting that these enzymes are not uniformly distributed in the Golgi apparatus structure.
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PMID:Biochemical studies on rat liver Golgi apparatus. II. Further characterization of isolated Golgi fraction. 20 81

A preparation, similar to the light mitochondrial fraction of rat liver (L fraction of de Duve et al, (1955, Biochem. J. 60: 604-617), was subfractionated by isopycnic centrifugation in a metrizamide gradient and the distribution of several marker enzymes was established. The granules were layered at the top or bottom of the gradient. In both cases, as ascertained by the enzyme distributions, the lysosomes are well separated from the peroxisomes. A good separation from mitochondria is obtained only when the L fraction if set down underneath the gradient. Taking into account the analytical centrifugation results, a procedure was devised to purify lysosomes from several grams of liver by centrifugation of an L fraction in a discontinuous metrizamide gradient. By this method, a fraction containing 10--12% of the whole liver lysosomes can be prepared. As inferred from the relative specific activity of marker enzymes, it can be estimated that lysosomes are purified between 66 and 80 times in this fraction. As ascertained by plasma membrane marker enzyme activity, the main contaminant could be the plasma membrane components. However, cytochemical tests for 5'AMPase and for acid phosphatase suggest that a large part of the plasma membrane marker enzyme activity present in the purified lysosome preparation could be associated with the lysosomal membrane. The procedure for the isolation of rat liver lysosomes described in this paper is compared with the already existing methods.
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PMID:Isolation of rat liver lysosomes by isopycnic centrifugation in a metrizamide gradient. 21 Nov 39

The intestinal epithelium of Ascardia galli has been studied with various cytological and cytochemical techniques. It consists of large epithelial cells resting on a thick collagenous basal lamina. Their luminal surface is provided with microvilli. The intestinal cells store considerable amounts of glycogen and neutral lipids. Some intracellular granular inclusions, which stain for proteins, phospholipids and lipoproteins, are distributed throughout the cytoplasm. The brush border is composed of microvilli whereas the outer surface coat consists of saliva resistant PAS-positive material. The detailed histochemical analysis of surface material has revealed that it is composed of nonacetylated acid mucopolysaccharides rich in hyaluronic acid with carboxylate polyanions. The brush border shows intense activities of acid phosphatase and glucose-6-phosphatase, moderate of ATPase, and lipase, weak of 5'-nucleotidase. Acid phosphatase-positive intracellular structures are seen in the intestinal epithelium which form distinct aggregations.
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PMID:Morphological and histochemical observations on the intestinal epithelium of Ascardia galli (Nematoda: Ascaridida). 21 46

A study has been made on the structure and chemical composition of the gut of Haemonchus contortus (Rud., 1803). The oesophagus has typically a triradiate, cuticle-lined lumen. The intestinal epithelium is provided with a well-developed brush border which contains periodic acid-Schiff-positive mucoproteins. The intestinal epithelium stores glycogen and lipids. It stains diffusely for phospholipids and general proteins and also for terminal-NH2 group. The presence of Fe2+ and Fe3+ containing pigments and activities of acid and alkaline phosphatases, glucose-6-phosphatase, and 5'-nucleotidase have been observed in the intestinal epithelium. Biochemically pH optimum for intestinal acid phosphatase has been found to be 4.8. The brush border shows positive reactions for acid phosphatase and glucose-6-phosphatase, and negative reactions for alkaline phosphatase and 5'-nucleotidase, and negative reactions for alkaline phosphatase and 5'-nucleotidase. The presence of enzymes in the brush border is related to extracellular digestion and absorption of nutrients.
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PMID:Morphological, histochemical, and biochemical studies on the gut of Haemonchus contortus Rud., 1803). 21 48

Vascular smooth muscle (VSM) cells from hypertensive and normotensive rat aortae and caudal arteries were isolated by enzymatic techniques, homogenized, and fractionated by differential pelleting. By these techniques, only mitochondria could be enriched more than fivefold in any one fraction. The other organelles were distributed heterogeneously in almost all fractions. Hypertensive smooth muscle enzyme distribution patterns were different from the normotensive, suggesting that changes in sedimentation characteristics had occurred. Activity of the enzyme 5'-nucleotidase increased in whole tissue homogenates and in the 'microsomal' fraction of aortic and caudal artery of hypertensive VSM. The lysosomal protease, cathepsin D, of hypertensive animals decreased in activity for both vascular smooth muscles while N-acetyl-beta-glucosaminidase and pNPPase (acid phosphatase) increased. The possibility of a functional deficiency in protein degradation causing lysosomal overloading is discussed.
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PMID:Alterations in lysosomes, catalase-containing organelles, mitochondria and plasma membrane fragments from hypertensive rat aorta and caudal artery. 21 41

A 5'-nucleotidase with unique specificity has been identified in the soluble fraction of normal human erythrocytes. It mediates the hydrolytic dephosphorylation of pyrimidine 5'-ribosemonophosphates but is catalytically ineffective with purine nucleotides or with the 2'-, 3'-, or cyclic isomers of pyrimidine nucleotides. Activities at 37 degrees in dialyzed hemolysates of nromal human erythrocytes averaged 7.3 and 6.2 mumol of Pi liberated per hour per g of hemoglobin for the substrates UMP and CMP, respectively. Activity with TMP as substrate was approximately one-half as much as with UMP or CMP. Apparent Michaelis constants were 0.33 mM UMP, 0.15 mM CMP, and 1.0 mM TMP. Magnesium was required for optimal activity, and this cation could not be replaced by Mn2+. Maximum activity was obtained between pH 7.0 and 7.5 with rapid decreases in more alkaline media and moderate decreases with acidification. The enzyme was quite sensitive to heat and was strongly inhibited by AMP, by some purine bases, and by both purine and pyrimidine nucleosides. Divalent cations of heavy metals were also strongly inhibitory, as were agents active against sulfhydryl groups. The presence of substrates and/or 2-mercaptoethanol provided considerable protection against some of these deleterious agents and conditions. Pyrimidine 5'-nucleotidase activity in hemolysates was clearly distinguishable from erythrocyte acid phosphatase and from leukocyte and serum alkaline phosphatases and nucleotidases.
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PMID:Characteristics of a pyrimidine-specific 5'-nucleotidase in human erythrocytes. 24 Aug 46

The regenerating forelimb of the adult newt, Notophthalmus viridescens was investigated for 5'-nucleotidase (5' ribonucleotide phosphohydrolase, 3.1.3.5) acitivity. The newt's humeri were surgically removed, and after a twenty-one-day recovery period, the forelimbs amputated above the elbows. Regenerates were sampled at predetermined times for specific phases in the progress of regeneration, frozen, sectioned in a cryostat, and the sections fixed in 10% cold formol calcium. The Wachstein and Meisel [25] lead procedure at neutral pH was used predominately in these experiments, although tests were also conducted with Gomori's [14] calcium, Allen's [21] highly alkaline procedures. The substrates used to obtain specific enzyme reactions were adenine, cytosine, guanine, uracil and inosine 5'-monophosphate nucleotides. Sodium beta-glycerophosphate served as a non-specific phosphomonoesterase substrate, distilled water replaced substrate, and inhibitors such as zinc and cyanide ions were used as control measures to assist in increasing the precision in interpreting the results obtained. The most reactive 5'-nucleotidase (5'-Nase) loci were in the walls of the blood vascular system, mysial and neural sheaths, dermis, and periosteum: the principal cells involved were macrophages, endothelium of blood vessels, and fibrocytes of connective tissues. A moderate enzyme response was elicited from secretory cells of some of the subcutaneous glands, hypertrophied chondrocytes and osteogenic centers, chondrocytes in the articular regions and within red blood cells and leucocytes. Normal, injured and degenerating, or regenerating striated muscle and nerve fibers were judged unreactive for 5'-Nase. The epidermis and wound epithelium displayed negative responses for 5'-Nase. Cells forming the regeneration blastema were 5'-Nase reactive during the early formative phase, but with growth and development of the blastema into bulb and conic forms, these cells did not respond for this enzyme-activity. One suggestion offered is that the absence of 5'-Nase in cells of the blastema may be related to the lack of an adequate blood-vascular supply. Several functions of 5'-Nase in normal and regenerating tissues are discussed. A basic conclusion reached is that 5'-nucleotidase hydrolyses may be more involved in fundamental anabolic than in catabolic metabolism.
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PMID:Localization of 5'-ribonucleotide phosphohydrolase in regenerating (and normal) limb tissues of the adult newt Notophthalmus viridescens. 24 77

Variations on the distribution of acid phosphatase and 5'-nucleotidase were observed among the cerebral nuclei of the Uromastix hardwickii. Most of the nuclei revealed more intensely positive reaction for 5'-nucleotidase than the acid phosphatase. However, an identical enzymatic pattern, demonstrating intense activity for the two enzymes, was observed in the cortical centers excepting the primordial hippocampus. The possible causes of the intensity and the functions of the enzymes were established in relation to the nuclei and fiber bundles.
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PMID:Chemoarchitectonics in a reptilian cerebral hemisphere--acid phosphatase and 5'-nucleotidase. 31 35


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