Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.6.1.3 (ATPase)
 65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Chylomicron remnants are catabolized by the liver, and their uptake within this organ is mediated by the presence of apolipoprotein (apo) E on the surface of these particles. In addition to a receptor for low density lipoproteins (LDL), several lines of evidence suggest that a unique receptor, referred to as the chylomicron remnant or apo E receptor, may be involved in the uptake of these lipoproteins. A possible candidate for the apo E receptor was previously isolated by affinity chromatography and was shown to possess high-affinity binding to apo E-containing lipoproteins, including chylomicron remnants, but not to possess high-affinity binding to apo B-containing LDL. However, it is now known that this fraction contains at least three proteins, all of which bind apo E with high affinity. An Mr congruent to 56,000 fraction contains two proteins that have been identified as the alpha- and beta-subunits of mitochondrial F1-adenosine 5'-triphosphatase (F1-ATPase). Furthermore, purified F1-ATPase binds apo E-containing lipoproteins with high affinity. It is very unlikely that these proteins, presumably isolated from mitochondrial membranes, are involved in chylomicron remnant metabolism. An Mr congruent to 59,000 fraction contains a unique apo E-binding protein that is not an ATPase. This protein appears to be localized to the endoplasmic reticulum of liver cells, but it is unclear whether this protein plays a role in chylomicron remnant catabolism. Furthermore, a cDNA clone coding for a protein that is apparently distinct from the ATPase and the Mr congruent to 59,000 protein has been obtained from a lambda gt11 library.(ABSTRACT TRUNCATED AT 250 WORDS)
Arteriosclerosis
PMID:Chylomicron remnant metabolism. Role of hepatic lipoprotein receptors in mediating uptake. 253 72

48 patients with cerebral arteriosclerosis were found to have a manifest release of adenylate kinase (AK) into cerebrospinal fluid (CSF). This release was most probably due to an increased leak in the brain cells subsequent to a lowered adenylate charge potential followed by a diminished electrochemical potential in these cells suffering from disturbed oxygen supply. A further increase of AK release into CSF was noted for the 22 patients receiving cardiac glycosides compared to the 26 patients not treated with these drugs. The mean AK value of the former group was 0.119 +/- 0.028 U/l compared to that of the latter group, being 0.089 +/- 0.025 U/l, and this difference was significant (p less than 0.001). The effect of cardiac glycosides is most probably explained by an additional lowering of the membrane electrochemical potential in brain cells of these patients due to the direct action of cardiac glycosides on the Na+- and K+-dependent ATPase system in these cells, resulting in an increased leak in the plasma membrane.
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PMID:Effect of cardiac glycosides on the release of adenylate kinase into cerebrospinal fluid of patients with cerebral arteriosclerosis. 628 88

Enzyme activity changes in reagent and neoplastic glia are examined. In the case of reagent glia, considerably increased ADPase, ATPase and AMPase values have been observed in experimental elective parenchymal necrosis in the rat, in hypertrophic astrocytes from recent plaques in multiple necrosis, in demyelinisation associated with cyanide encephalopathy, and in reagent astrocytes surrounding tumours and arteriosclerosis sites. Depressed ATPase values have been observed in experimental oedema, as compared with increased TPPase in human oedema. BuChE and ChE activity disappears in both oligodendro- and astroglia near old cerebral infarct sites, whereas there is marked BuChE activity peripherally to multiple sclerosis plaques and in areas of phenylpyruvic oligophrenia demyelinisation. In neoplastic glia, ADPase is clearly evident in malignant gliomas, ATPase is related to the extent of the cell body, AMPase is positive in medulloblastoma cell cytoplasm and beta-glucuronidase increases in anaplasia. Above-normal ChE activity has been observed in astrocyte tumors, while BuChE is greater than that of AChE. Phosphorylase reaction is intense in astrocytoma and in glioblastoma giant cells. Phosphoglucomutase values are below-normal in tumours, except in the case of ependymoma, while both phosphohexoisomerase and hexokinase display increased activity in atypical forms.
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PMID:[Histochemical demonstration of glial enzyme activity. II. Reagent and neoplastic glia]. 1734 Aug 8