Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.6.1.3 (ATPase)
65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A case of glomus tumor was studied by light and electron microscopic enzyme histochemistry. Histologically, this case was classified as glomangioma or vascular form of glomus tumor. The tumor cells had ultrastructural characteristics of smooth muscle cells such as large amount of thin filaments with dense bodies, basal lamina and numerous pinocytotic vesicles. Among the 3 membrane associated enzymes, namely alkaline phosphatase, adenosine triphosphatase (ATPase) and 5'nucleotidase, only ATPase was detectable in the cell membrane and pinocytotic vesicles. It is suggested that the ATPase activity of the tumor cells shows additional evidence of smooth muscle character of glomus tumor.
...
PMID:Histochemical evidence of adenosine triphosphatase activity in glomus tumor--report of a case. 609 31

The study deals with the histoenzymological architecture of the rhomencephalon and mesencephalon of a fresh water turtle. Attempt has been made to see the location of phosphatases (acid and alkaline phosphatases, 5-nucleotidase, adenosine triphosphatase) in the different constituents of these brain areas. The distribution of acid phosphatase is similar to Nissl staining, hence the enzyme has been used as a marker to differentiate various nuclei in the different brain areas. Moreover, the concentration of acid phosphatase is higher in large neurons like that of Nissl substance and, therefore, all such cells are quite distinct. Alkaline phosphatase predominates in blood vessels. Neuropil and neuronal activity of this enzyme is restricted to limited nuclei, only. 5-nucleotidase is localized in all the cells as well as in the neuropil. Adenosine triphosphatase activity is quite strong in all the brain areas irrespective of their sensory and motor nature. In turtle brain it has not been possible to distinguish sensory and motor areas on the basis of phosphatases distribution as calimed in fishes and mammals by several workers. Significance of the enzymes at various locales has been brought out in the contribution.
...
PMID:A comparative study of phosphatases in the rhombencephalon and mesencephalon of fresh water turtle (Lissemys punctata granosa). 609 5

Using electron microscope cytochemistry and cells separated on Ficoll-Hypaque, Mg2+-dependent ATPase, ADPase and 5'-nucleotidase were predominantly localized as ectoenzymes on normal human granulocytes. Large deposits of ATPase final reaction product and more finely granular deposits of 5'-nucleotidase final reaction product were firmly attached to the outer surface of cell plasma membranes. The final reaction product from ecto-ADPase was, however, only loosely associated with the plasma membrane. In addition, finer deposits of ADPase final reaction product were seen in specific granules and in background cytoplasm. No nucleotidase phosphatase activity was localized to the alkaline phosphatase-containing granules (phosphasomes) recently described by Rustin et al. In granulocytes from patients with chronic granulocytic leukaemia, ecto-ATPase had a patchy distribution on the plasma membranes. There was considerable heterogeneity between cells with regard to ADPase and 5'-nucleotidase localization. In some cells, ADPase was seen only at both site, while in some cells no activity was detected. 5'-Nucleotidase localization was normal in some cells but lacking from many. No correlation was found between enzyme heterogeneity and the degree of morphological cell maturity.
...
PMID:Electron microscopic cytochemical localization of nucleoside phosphatases in normal and chronic granulocytic leukaemic human neutrophils. 611 13

Several enzymes associated with the hepatocyte cell surface, alkaline phosphatase (AP), 5'-nucleotidase (5'N), Mg++- and total Na+K+Mg++-ATpase, were assayed and localized cytochemically in order to gain insight into alterations of the plasma membrane components during reassociation of hepatocytes in primary monolayer culture. During a period of 4 days the activities of 5'nucleotidase and alkaline phosphatase increased spontaneously up to three- and four-fold, respectively. Dexamethasone reinforce the rise of alkaline phosphatase activity but retarded the increase of that of 5'nucleotidase. However, after the third day the level of 5'nucleotidase activity converged with the untreated controls. The activities of Mg++- and Na+K+Mg++-ATPase, which closely paralleled each other, remained essentially unchanged throughout cultivation and were not affected by dexamethasone. Cytochemical demonstration of alkaline phosphatase, 5'nucleotidase and Mg++-ATPase, using the lead salt method, revealed the potential presence of reaction product on the whole cell surface. However, the cells did not react uniformly, particularly on bile canalicular membranes. This heterogeneity seems to be due to different stages of canalicular development and to different functional states of the cultured hepatocytes.
...
PMID:Alterations in activity and ultrastructural localization of several phosphatases on the surface of adult rat hepatocytes in primary monolayer culture. 612 58

Tissue sections of lymph nodes, appendices and tonsils, together with smears of immunologically separated peripheral lymphoid cells from a B-CLL and lymphomatous cells from an immunocytoma were submitted to combined enzyme cytochemical investigations with acid alpha-naphthyl acetate esterase (ANAE), beta-glucuronidase (B-G), acid phosphatase (AcPh), adenosine triphosphatase (ATPase), a,d 5'nucleotidase (5'N). T-cells were Acph+, ATPase- and 5'N-. The vast majority of T- and B-cells displayed ANAE and B-G activities with two distinct staining patterns (T-like and B-like pattern). A high proportion of lymphoid cells in the germinal centre (G.C.) and the vast majority of lymphoid cells in the mantle-zone (M.Z.) were shown to belong to B-cell system because of the expression of ATPase and 5'N in their membranes. Some lymphoid cells positive for ANAE and B-G with a B-like pattern and for AcPh were recognizable in the G.C. In the M.Z. only a few lymphoid cells being ANAE+, with a T-like pattern, and AcPh+ were shown to belong to the T-cell system. In contrast, in this zone a high proportion of small lymphoid cells (64% +/- 10%) showed ANAE activity, mostly with B-like pattern. Therefore, these findings indicate that in the M.Z. a high proportion of B-cells ATPase+ and 5'N+ also display ANAE activity. By comparison of the results obtained from lymphoid tissue sections, B-CLL and immunocytoma cell suspensions and normal circulating lymphocytes we can conclude that B-ANAE-positive cells of the M.Z. do not usually appear in the peripheral blood. They circulate in large numbers only in some pathological conditions (like our reported B-CLL). Therefore, B-ANAE-positive lymphoid cells of the mantle, with a B-like staining pattern, include a wide range of subsets which exclude large lymphoid cells and plasma cells.
...
PMID:Histochemical study on human germinal centre, mantle-zone and extra-follicular area lymphoid cell subpopulations. Immunological and cytochemical correlations with lymphomatous cells, peripheral normal and leukemic lymphocytes. 613 70

Synaptosomes isolated from the electric organ of Torpedo marmorata contain activity of an ATPase which is located at the extracellular face of the plasma membrane. Ecto-ATPase activity can be stimulated independently and to a similar extent by either Ca-2+ or Mg-2+. Apparent Km-values for ATP are 79 microM and 53 microM for Ca-2+ and Mg-2+ respectively. Apparent Km-values for Ca-2+ and Mg-2+ at 1 mM ATP are 0.71 mM and 0.61 mM respectively. The enzyme is also activated by Mn-2+ and GTP can replace ATP as a substrate. Presence of 5'- nucleotidase activity suggests that adenosine is the final hydrolysis product. Thus hydrolysis of nucleotides released during exocytosis of synaptic vesicle contents and purine salvage must be a major role of this ecto-enzyme. We furthermore suggest that the ecto-ATPase may provide the key to understanding the storage of the high energy compound ATP in cholinergic synaptic vesicles. On depolarization of the nerve terminal and exocytosis, ATP represents the signal for activating the ATPase whereby concentrations of Ca-2+ and Mg-2+ are already saturating. Following depolarization induced Ca-2+ influx, a possible function of the ATPase may be the outward transport of Ca-2+ from the nerve terminal.
...
PMID:Ecto-adenosine triphosphatase activity at the cholinergic nerve endings of the Torpedo electric organ. 614 82

Administration of N-hydroxy-2-acetylaminofluorene (90 mumol/kg, iv) to rats results in damage to periportal hepatocytes. The most prominent ultrastructural changes are the appearance of numerous unusual vesicles of about 200 nm diameter and the proliferation of the endoplasmic reticulum to form fingerprint-like structures. In order to characterize these vesicles and to investigate their possible origin, their enzymatic activity was studied by ultrastructural enzyme histochemistry. The vesicles as well as the fingerprint-like structures exhibited glucose-6-phosphatase activity. Continuities between the vesicles and the membranes of both the RER and the SER were frequently seen. The vesicles lacked ATPase, 5'nucleotidase and catalase activity. From these results we conclude that the vesicles may be an unusual proliferation of the endoplasmic reticulum.
...
PMID:Genesis of unusual vesicles in rat periportal hepatocytes after administration of N-hydroxy-2-acetylaminofluorene. 614 30

The effects of ethanol on the activities of five membrane bound enzymes were determined using a crude membrane preparation obtained from cortex of long-sleep (LS) and short-sleep (SS) mice. These two mouse lines were selectively bred for differences in duration of ethanol-induced sleep time. The enzymes studied were two forms of NaK-ATPase, Mg-ATPase, 5'nucleotidase, and acetylcholinesterase. Arrhenius plots of the ethanol-temperature-enzyme activity studies indicate specificity in ethanol's actions. NaK-ATPase activity consists of two enzymes which were distinguished by sensitivity to ouabain. The Arrhenius plot of the high ouabain sensitivity enzyme (low Ki) exhibited a transition temperature which was reduced twice as much by ethanol in LS membranes as in SS membranes. Ethanol did not affect the transition temperature of the high Ki NaK-ATPase but the control (no ethanol) transition temperature was 2.7 degrees higher in SS membranes. Arrhenius plots of Mg-ATPase activity did not exhibit a transition temperature and ethanol did not alter enzyme activity. Ethanol did not alter the transition temperatures of 5'nucleotidase or acetylcholinesterase but the control transition temperature for acetylcholinesterase was 2.3 degrees higher in SS membranes. These results indicate specificity in ethanol's actions on membranes and that inhibition of the lipid-enzyme interactions for the low Ki NaK-ATPase is correlated with the difference in sensitivity to ethanol seen between the LS and SS mice.
...
PMID:Ethanol and temperature effects on five membrane bound enzymes. 615 1

It has been concluded from the studies on the activity and location of ATPase and 5-nucleotidase in mammary and gastric tumours that some neoplasms of the mammary gland and stomach showing a high ATPase activity are histochemically related, in the former case, to the lobular myoepithelium and in the latter case, to non-differentiated cells of gastric glands which acquired a capacity for intestinal metaplasia and preserved it in the course of malignant transformation. No essential changes have been recorded in the activity of 5-nucleotidase, depending on the tumour histologic structure and degree of its maturity.
...
PMID:[ATPase and 5-nucleotidase in human breast and stomach tumors]. 624 2

The lipid composition and fluidity of plasma membranes have been studied at different stages of liver regeneration (4, 15 and 24 h after surgery). The phospholipid and fatty acid composition is not modified, whereas the cholesterol/phospholipid ratio is lower with respect to control membranes. The modification of the physical properties of the membranes has been studied directly by EPR analysis and indirectly by temperature dependence and cooperativity of some membrane-bound enzymes (Mg2+-ATPase, (Na+ + K+)-ATPase and 5'nucleotidase). Surgical operation or anaesthesia alone causes an early increase in fluidity; such an effect appears to be markedly reduced at a later stage. There seems to be a marked effect of regeneration on plasma membrane fluidity 15 h after partial hepatectomy when several parameters--surface fluidity, cholesterol/phospholipid ratio, and 5'-nucleotidase activity in the presence of concanavalin A -- are modified and indicate an increase in membrane fluidity. It is suggested that this modification of membrane properties could be related to the proliferative process.
...
PMID:Plasma membrane changes associated with rat liver regeneration. 624 90


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---