Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20020 (adenosine triphosphatase)
 3,299 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Localization of phosphatases in the parathyroid of laying hens was examined by electron microscopy. Activities of both alkaline phosphatase and adenosine triphosphatase were intensive on the apposed plasma membranes between contiguous chief cells, but weak or almost lacking on those facing the interstitial connective tissue, and this finding differed from previous data in mammals. This difference seemed to be associated with the fact that in the parenchymal cells of the hens there was found a narrow, delicate filament-rich zone in the peripheral cytoplasm along the basal lamina. Activities of both thiamine pyrophosphatase and inosine diphosphatase were seen in most of the Golgi cisternae having serpentine tubular profiles, and this indicated that the latter cisterna belong to the Golgi apparatus. Acid phosphatase activities were mainly demonstrated in lysosomal dense bodies, including autophagic vacuoles, as well as in most of the lipofuscin granules, and only occasionally encountered in the Golgi apparatus, including the thick membranous cisternae, in contrast with findings in mammals. The reason for this weak activity in this organelle was discussed in relation to calcium metabolism, secretory products, and lysosomes in the laying hen.
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PMID:Electron microscopic studies on localization of phosphatases in the laying hen parathyroid. 626 87

In op/op mice, immunohistochemical and electron microscopic techniques were used to examine the effects of the OP mutation on dendritic cell populations in lymphoid tissues and skin. In the thymic medulla, T cell zone of lymph nodes, and splenic white pulp of op/op mice, numbers of NLDC-145-positive dendritic cells were not decreased. Compared to the normal littermates, numbers of BM8-positive macrophages were reduced in various tissues of the mutant mice, including the lymphoid tissues. These dendritic cells of op/op mice expressed Ia antigens but not F4/80 and BM8 antigens. Ultrastructurally, the dendritic cells developed a tubulovesicular system typical of interdigitating cells, but they were abnormal in that interdigitation of their cytoplasmic processes was not prominent. In the epidermis of the op/op mice, dendritic cells expressed NLDC-145, F4/80, Ia antigens, and adenosine diphosphatase or adenosine triphosphatase activity, and numbers of NLDC-145-, Ia-, or ADPase-positive dendritic cells were reduced slightly, but these reductions were not significant statistically. Birbeck granules were detected in most of them electron microscopically. These results indicate that nonlymphoid dendritic cells develop in the lymphoid tissues and skin of op/op mouse, suggesting that they are differentiated from granulocyte-macrophage colony-forming cells or earlier hematopoietic cell precursors.
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PMID:Differentiation of dendritic cell populations in macrophage colony-stimulating factor-deficient mice homozygous for the osteopetrosis (op) mutation. 842 88

Although the submandibular gland of ferret is useful for studying salivary secretory processes which are regulated by nerves and involve myoepithelial activity, little attention has been paid to its parenchymal innervation and myoepithelial arrangements. Therefore, glands obtained postmortem from mature ferrets of both sexes were here examined with the use of light-microscopic histochemical techniques for cholinesterases, phosphatases and phosphorylase, histofluorescence for catecholamines, and milling dyes. Acetylcholinesterase staining was associated with nerve trunks in the interlobular stroma and an extensive intralobular network of nerve fibres, presumably of a cholinergic type, embracing acini and ducts. There were fewer fibres containing fluorescing catecholamines, presumably adrenergic. They were largely associated with acini. Numerous stellate cells with fine branching processes embracing acini, presumably myoepithelial cells, and a few spindle-shaped basal cells, investing striated ducts, were demonstrated on frozen tissue by alkaline phosphatase, but not by adenosine triphosphatase, inosine diphosphatase and phosphorylase. Cells of similar shape and distribution were also demonstrated by staining with milling dyes on fixed tissues, indicating possibly a filamentous constituent conferring mechanical stability and/or contractile ability. Together, these results suggest, firstly, that a cholinergic-type parenchymal innervation is prominent in the submandibular gland of ferret, although many adrenergic nerves are also present, and, secondly that the gland has a very extensive myoepithelial network which is possibly involved in membrane transport, and the support and or contraction of the secretory parenchyma.
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PMID:Innervation and myoepithelial arrangements in the submandibular salivary gland of ferret investigated by enzyme, catecholamine and filament histochemistry. 1066 82

Tissue fractionation was used as an analytical tool to study the subcellular distribution of an adenosine triphosphatase activated by Mg2+ in adrenal medullae of the pig and ox and in whole adrenals of the rat. By measuring adenosine triphosphatase and various enzymes in the fractions obtained by differential centrifugation, the distribution pattern of adenosine triphosphatase was found to differ markedly from that of markers like catecholamines, dopamine beta-hydroxylase or cytochrome oxidase. In the pig and ox the distribution of inosine diphosphatase paralleled that of adenosine triphosphatase. After equilibration through sucrose density gradients, no adenosine triphosphatase activity was detected in the chromaffin granules in the rat. However, in bovine adrenal medullae, a large part of the adenosine triphosphatase activity equilibrated in that area of the gradient in which the chromaffin granules were found. This adenosine triphosphatase distribution pattern was an artefact produced by applying a too concentrated sample to the gradient. When a more diluted sample of bovine tissue was used no adenosine triphosphatase activity was found to be associated with the chromaffin granules. The present results lead to a reconsideration of the role of the adenosine triphosphatase in some processes in which the chromaffin granules are involved. Moreover, the degree of purity of many chromaffin granule preparations is again questioned.
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PMID:Tissue fractionation and catecholamines--IV. Adenosine triphosphatase in chromaffin granules: a distribution artefact. 1137 Feb 33

Members of the ecto-nucleoside triphosphate diphosphohydrolase (eNTPDase) family exhibit distinctive substrate specificities, but how such specificities are achieved by enzymes with identical putative catalytic domains is unknown. Previously we showed that H59G substitution changes CD39 from an apyrase to an adenosine diphosphatase (ADPase) in a manner that depends on intact associations of both transmembrane domains with the membrane. Here we show that the extracellular domain of CD39L1 ecto-adenosine triphosphatase (ecto-ATPase) has the same 3:1 ATP:ADP hydrolysis ratio as the extracellular domain of CD39, suggesting that the transmembrane domains are required to confer the native substrate specificities on each enzyme. As in CD39, H50G substitution has little effect on the activity of the CD39L1 extracellular domain or solubilized monomers. However, H50G substitution diminishes both ATPase and ADPase activities of native CD39L1, in contrast to its selective effect on ATPase activity in CD39, suggesting that the transmembrane domains confer different ADP hydrolysis mechanisms on CD39 and CD39L1. We then show that the transmembrane domains of CD39L1 can substitute for those of CD39 in conferring native CD39 substrate specificity and regulation of H59 but that the transmembrane domains of CD39 confer neither CD39 nor CD39L1 properties on the CD39L1 extracellular domain. These results suggest that non-apyrase conserved region residues in the extracellular domain contain the information specifying CD39 native properties but have a nonspecific requirement for two transmembrane domains to manifest the information.
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PMID:Transmembrane domains confer different substrate specificities and adenosine diphosphate hydrolysis mechanisms on CD39, CD39L1, and chimeras. 1182 41

Schistosomiasis is one of the most important human parasitic diseases. One of the possible methods for the control is through the molluscan intermediate host of the parasite. Biomphalaria arabica, molluscan hosts to Schistosoma mansoni in Saudi Arabia were treated with sublethal concentrations (LC25) of dry powdered leaves Solanum nigrum. Effect of plant on ectonucleotidases (NTPdases) (ADPase & ATPase), sodium/potassium adenosine triphosphatase (Na+/K+ ATPase) and creatine kinase (CK) was traced. The plant molluscicide was potent in inhibiting the four investigated enzymes giving a percentage inhibition range between 45-55%. The effect of the inhibited enzymes on the compatibility of the snail hosts to schistosome parasite was discussed. In conclusion, the use of sublethal concentration of S. nigrum to disturb the biochemical profile of the snail hosts could be a promising and safe strategy to control the disease.
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PMID:Effect of plant molluscicides on selected enzymes related to energy metabolism in Biomphalaria arabica snails molluscan hosts to Schistosoma mansoni in Saudi Arabia. 2050 97

Cardiovascular disease, including atherosclerosis, is the leading cause of death in patients with diabetes worldwide; thus, it is a major medical concern. The endothelium contributes to the control of many vascular functions, and clinical observations show that it is a primary target for diabetic syndrome. To get better insight into the mechanisms underlying atherosclerosis, we studied the interspecific differences in the arterial metabolisms of two, Psammomys obesus and Gerbillus gerbillus, as well as Rattus norvegicus (Wistar rat), well known for its atheroresistance. Twenty-two enzymatic activities and six macromolecular substances were histochemically compared in the two desert species and in Wistar aortas (abdominal and thoracic) and arteries (femoral and caudal) embedded in a common block. In the healthy adult rodents, enzyme activities were very intense. They demonstrated that aortic myocytes are capable of various synthesis and catabolism processes. However, considering the frequency of atherosclerosis and its phenotypes, significant differences appeared between the species studied. Our comparative study shows that aortic atherosensitive animals have several common metabolic characteristics, which are found in Psammomys rich in metachromatic glycosaminoglycans (involved in the inhibition of lipolysis and in calcification of the organic matrix), reduced activity in enzymes related to the Krebs cycle (weakening energetic power), and low lipolytic enzyme, adenosine triphosphatase, and adenosine diphosphatase activities. However, the most fundamental pathophysiological difference is the low lipolytic power of the aorta of Psammomys when compared to Wistar rats. This characteristic determines its atherosensitivity and makes this animal model more applicable to the experimental development of atherosclerosis.
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PMID:Atherosclerosis and atherosensitivity in two southwest Algerian desert rodents, Psammomys obesus and Gerbillus gerbillus, and in Rattus norvegicus. 2305 58

In homogenates of stem sections from etiolated pea (Pisum sativum L.) seedlings, secretory vesicles can be separated from Golgi-apparatus cisternae by rate-zonal centrifugation in renografin gradients. Optically, two bands of turbidity are observed, the uppermost containing the secretory vesicles and the lower one the Golgi-apparatus cisternae. The absence of glutaraldehyde in the homogenizing medium has allowed the effective characterization of marker-enzyme activities. Golgi-apparatus cisternae have been recognized by the presence of inosine-diphosphatase and glucan-synthase I activities as well as by electron microscopy. In contrast, although secretory vesicles also bear inosine diphosphatase they do not appear to possess glucan-synthase activity. Three plasma-membrane markers, NPA-binding, glucan synthase II, and KCl,Mg(2+)-adenosine triphosphatase (pH 6.5), were not detected in secretory vesicles. Pulse-chase experiments with [(3)H]glucose support our designation of secretory vesicles and Golgi-cisternal fractions.
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PMID:Identification of secretory vesicles in homogenates of pea stem segments. 2426 26


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