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

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Query: EC:3.1.3.1 (alkaline phosphatase)
47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have studied the immunohistochemical reactivity and ultrastructure of both neurofibrillary tangles (NFTs) occurring with severe neurofibrillary diseases, and Pick bodies (PBs) associated with Pick's disease. The NFTs and PBs did not react immunohistochemically with the anti-nonphosphorylated neurofilament monoclonal antibody irrespective of whether they were pretreated with alkaline phosphatase. In granular neurons of the dentate fascia of Ammon's horn in cases of dementia of the Alzheimer type (DAT), NFTs either resembled PB-like inclusion bodies (Horoupian's inclusion bodies) in form, or had a perinuclear structure. Immunohistochemically and ultrastructurally, the NFTs in the dentate fascia in cases of DAT, including Horoupian's inclusion bodies, were similar to the NFTs in the pyramidal neurons of Ammon's horn, which are found most frequently in association with severe neurofibrillary diseases. Under a light microscope, Horoupian's inclusion bodies and PBs could not be differentiated and appeared to be argyrophilic round cytoplasmic inclusions in granular neurons of the dentate fascia. There were, however, ultrastructural differences. Horoupian's inclusion bodies consisted of bundles made up of straight tubules (STs), each about 15 nm in diameter. These bundles were intermixed with a few paired helical filaments which occurred at intervals of about 80 nm. On the other hand, PBs were composed of randomly distributed 15-nm-wide STs, intermixed with a very few fibrillary structures. These fibrils had a periodicity of about 160 nm, and ranged in width from about 15 nm to 30 nm. Horoupian's inclusion bodies associated with DAT and PBs associated with Pick's disease are different in this neuropathological aspect.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Reappraisal of neurofibrillary tangles. Immunohistochemical, ultrastructural, and immunoelectron microscopical studies. 253 41

Cerebral cortical microvessels were prepared from control, dementia of Alzheimer type (AD/SDAT) and multi-infarct dementia (MID) autopsy cases. The microvessel yields were approx. 200 micrograms protein/g starting material, and did not differ significantly between control, MID and AD/SDAT groups. The purity of the preparations was confirmed both by light and electron microscopy and by measurement of enrichment of the endothelial markers gamma-glutamyltranspeptidase and alkaline phosphatase. Higher microvessel alkaline phosphatase activities and higher microvessel/homogenate ratios of activities of both enzymes in the MID and the AD/SDAT samples than in the control samples were found, which may be consistent with previous findings of structural abnormalities of the cerebral endothelial cells in AD/SDAT. The levels of [3H]prazosin binding did not differ significantly between control. MID and AD/SDAT samples at any [ligand] tested (0.05, 0.1, and 0.5 nM), suggesting conservation of microvessel alpha 1-adrenoceptors in MID and AD/SDAT.
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PMID:Alpha 1-adrenergic receptor binding sites in post-mortal human cerebral microvessel preparations: preservation in multi-infarct dementia and dementia of Alzheimer type. 255 46

A monoclonal antibody, NOAL 6.423 has been produced which unequivocally identifies a protein which is a constituent of the pronase resistant core of the Alzheimer PHF. Although the site recognised by this antibody is contained somewhere within the highly conserved triple repeat region of the tau molecule, no experiments have succeeded so far in demonstrating NOAL 6.423 reactivity in any brain proteins other than those derived from PHFs. A site which can be recognised by NOAL 6.423 cannot be generated in preparations of normal porcine tau by simple proteolytic cleavage with pronase. Likewise reactivity with the PHF peptide recognised by NOAL 6.423 is not altered by alkaline phosphatase. The unusual properties of NOAL 6.423 are consistent with the possibility that its recognition site is not determined solely by the primary structure of the conserved region of the tau molecule.
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PMID:Characterisation of the first monoclonal antibody against the pronase resistant core of the Alzheimer PHF. 260 35

An immunocytochemical study of alpha 1-antichymotrypsin (alpha 1ACT) was performed in order to demonstrate its localization and the relationship between alpha 1ACT and senescent cerebral amyloid. We examined 5 brains with dementia of the Alzheimer type (SDAT), a peripheral nerves of familial amyloidotic polyneuropathy (variant transthyretin type, FAP) and dorsal root ganglions of a primary amyloidosis with peripheral neuropathy (AL type, PA). Avidin-biotin-peroxidase complex method and double immunoenzymatic staining method (peroxidase-antiperoxidase method combined with avidin-biotin-alkaline phosphatase complex method) were used. Anti-beta protein serum was used as the marker of cerebral amyloid. About 98% of senile plaques had alpha 1ACT like-immunoreactivity (alpha 1ACTI). All types of plaques showed the immunoreactivity: Core and peripheral of typical plaques, primitive plaques, core plaques and amorphous cerebral amyloid deposits. Although, a part of a senile plaque showed beta protein like-immunoreactivity alone and the other part had alpha 1ACT, many remainder part of a senile plaque had both immunoreactivity. Of the other pathological changes of SDAT, eosinophilic tangles and cerebrovascular amyloid were positive, in contrast, intracellular tangles, granulovacuolar degeneration and Hirano body were negative. The amyloid from FAP had weak alpha 1ACTI and diffusely stained. alpha 1ACTI was seen in the peripheral margin of the amyloid from PA. These results indicate that alpha 1ACT is closely associated with senile plaques formation.
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PMID:[An immunocytochemical study of alpha 1-antichymotrypsin in the senescent cerebral amyloid]. 266 94

A monoclonal antibody to the microtubule-associated protein tau (tau) labeled some neurofibrillary tangles and plaque neurites, the two major locations of paired-helical filaments (PHF), in Alzheimer disease brain. The antibody also labeled isolated PHF that had been repeatedly washed with NaDodSO4. Dephosphorylation of the tissue sections with alkaline phosphatase prior to immunolabeling dramatically increased the number of tangles and plaques recognized by the antibody. The plaque core amyloid was not stained in either dephosphorylated or nondephosphorylated tissue sections. On immunoblots PHF polypeptides were labeled readily only when dephosphorylated. In contrast, a commercially available monoclonal antibody to a phosphorylated epitope of neurofilaments that labeled the tangles and the plaque neurites in tissue did not label any PHF polypeptides on immunoblots. The PHF polypeptides, labeled with the monoclonal antibody to tau, electrophoresed with those polypeptides recognized by antibodies to isolated PHF. The antibody to tau-labeled microtubules from normal human brains assembled in vitro but identically treated Alzheimer brain preparations had to be dephosphorylated to be completely recognized by this antibody. These findings suggest that tau in Alzheimer brain is an abnormally phosphorylated protein component of PHF.
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PMID:Abnormal phosphorylation of the microtubule-associated protein tau (tau) in Alzheimer cytoskeletal pathology. 308 67

Microtubule-associated protein tau was characterized in 5 Alzheimer and 5 control brains using two monoclonal antibodies, Alz 50 and Tau-1. Quantitative analysis of immunoblots with the antibodies showed that both homogenate and supernatant fractions (12,000 x g) from Alzheimer brains contained 38-65% less tau immunoreactivity compared to normal brains. The reduction was found in all brain regions studied (frontal and temporal lobes and thalamus) and in both gray and white matter. In partially purified tau preparations, the yield of protein was lower in Alzheimer (by 35%) than in control brain. Incubation of brain proteins, transferred onto nitrocellulose paper, with alkaline phosphatase had either no effect or slightly increased the antibody binding to tau proteins from both brain tissues. Immunoblots of tau-enriched preparations subjected to two-dimensional gel electrophoresis showed no major changes in the staining pattern of tau isoforms in Alzheimer samples except for a weaker reactivity of the basic isovariants as compared to non-Alzheimer samples. The elution volume of tau from Alzheimer brain supernatant on a Sepharose CL-6B column was similar to that from non-Alzheimer brain and equal to that of aldolase (Mr = 158,000). Our data suggest that most of tau proteins from both types of brain have similar biochemical properties. The reduction in tau reactivity in Alzheimer tissue may be due to a reduction in neuronal cell population or incorporation of soluble tau into stable structures such as neurofibrillary tangles, since the tangles have been shown to react with anti-tau antibodies.
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PMID:Immunochemical and biochemical characterization of tau proteins in normal and Alzheimer's disease brains with Alz 50 and Tau-1. 313 34

Antisera were raised in rabbits to purified bovine tau and to isolated Alzheimer paired helical filaments (PHF) washed with sodium dodecyl sulfate (SDS). Both anti-tau and anti-PHF sera labeled at electron microscopic level PHF which had been isolated either by extraction with SDS or treatment with crude collagenase. On immunoblots all anti-tau and anti-PHF sera labeled bovine brain tau as well as the major 45- to 62-kDa PHF polypeptides which had been previously shown to co-migrate on SDS gels with normal human tau (J. Biol. Chem., 261 (1986) 6084-6089). All antisera labeled Alzheimer neurofibrillary tangles on tissue sections and the PHF polypeptides on immunoblots. Pretreatment with alkaline phosphatase had no effect on the immunostaining. The antisera did not react with ubiquitin, neurofilament triplet polypeptides and with the exception of one antiserum with tubulin and high-molecular weight microtubule-associated proteins. Absorption of tau antisera with tau and PHF and of PHF antisera with PHF resulted in complete removal of the tangles-staining antibodies. In case of the anti-PHF sera when adsorbed with tau, only the staining of a certain tangles population, the dense type, was eliminated and that too at more than 20 times the amount needed for the anti-tau sera; the staining of the loosely packed type of tangles, presumably the final stage, gradually decreased but was not completely abolished. On immunoblots the tau-like major PHF bands remained labeled by the tau-absorbed anti-PHF sera.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Microtubule-associated polypeptides tau are altered in Alzheimer paired helical filaments. 314 Oct 8

We examined the possibility that neurofibrillary tangles (NFTs) were heterogeneous in postmortem hippocampus from 22 patients with or without senile dementia of the Alzheimer type. Intraneuronal NFTs and extracellular, or "ghost," NFTs were recognized in situ by only one or the other of two monoclonal antibodies. The first monoclonal antibody, RMO87, stained only intraneuronal NFTs and is specific for phosphate-dependent epitopes in tau and the two high molecular weight neurofilament proteins. The second monoclonal antibody, 2.2B10, is specific for glial fibrillary acidic protein, and it stained only the RMO87-negative extracellular NFTs. Treatment of sections with alkaline phosphatase or sodium dodecyl sulfate, and the isolation of NFTs from hippocampus, did not expose RMO87 binding sites in extracellular NFTs. These observations indicate that neurofilament-like and tau-like epitopes can be lost from NFTs in situ, and that at least two populations of morphologically and immunochemically distinct NFTs exist.
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PMID:Intraneuronal and extracellular neurofibrillary tangles exhibit mutually exclusive cytoskeletal antigens. 337 39

Cholinergic neurons are unique among cells since they alone utilize choline not only as a component of major membrane phospholipids, such as phosphatidylcholine (Ptd-Cho), but also as a precursor of their neurotransmitter acetylcholine (AcCho). It has been hypothesized that choline-phospholipids might serve as a storage pool of choline for AcCho synthesis. The selective vulnerability of cholinergic neurons in certain neurodegenerative diseases (e.g., Alzheimer disease, motor neuron disorders) might result from the abnormally accelerated liberation of choline (to be used as precursor of AcCho) from membrane phospholipids, resulting in altered membrane composition and function and compromised neuronal viability. However, the proposed metabolic link between membrane turnover and AcCho synthesis has been difficult to demonstrate because of the heterogeneity of the preparations used. Here we used a population of purely cholinergic cells (human neuroblastoma, LA-N-2), incubated in the presence of [methyl-3H]methionine to selectively label PtdCho synthesized by methylation of phosphatidylethanolamine, the only pathway of de novo choline synthesis. PtdCho, purified by thin-layer chromatography, contained 90% of the label incorporated into lipids, demonstrating that LA-N-2 cells contained phosphatidylethanolamine N-methyltransferase. Three peaks of radioactive material that cochromatographed with authentic Ac-Cho, choline, and phosphocholine were observed when the water-soluble metabolites of the [3H]PtdCho were purified by high-performance liquid chromatography. Their identities were ascertained by subjecting them to enzymatic modifications with acetylcholinesterase, choline oxidase, and alkaline phosphatase, respectively. The results demonstrate that AcCho can be synthesized from choline derived from the degradation of endogenous PtdCho formed de novo by methylation of phosphatidylethanolamine.
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PMID:Synthesis of acetylcholine from choline derived from phosphatidylcholine in a human neuronal cell line. 347 63

Eight foals, 2 to 5 days of age, with similar clinical signs and laboratory and pathologic findings, died from hepatic failure. The predominant clinical signs were depression and icterus. Abnormally high values were found for plasma ammonia content, aromatic-to-branch-chain amino acid ratio, total serum bilirubin content, gamma glutamyl transferase activity, alkaline phosphatase activity, and PCV; partial thromboplastin time and prothrombin time were prolonged. Some foals had high sorbitol dehydrogenase activity. These laboratory findings were suggestive of subacute hepatic disease and failure. Predominant pathologic findings were limited to the liver and brain. The livers were less than half the expected size for 2- to 5-day-old foals, had prominent bile ductule proliferation, hepatic cell necrosis, and mild periportal fibrosis. These findings suggested both prenatal and postnatal diseases caused by exposure to a hepatoxin. The predominant lesion in the brain was the presence of Alzheimer type II astrocytes, which are characteristic of hepatoencephalopathy. Although the periportal fibrosis was suggestive of in utero exposure to a toxin, epidemiologic information suggested that the hepatic failure more likely resulted from oral inoculation of a microorganism culture product at birth. The same disease was reproduced in 2 newborn foals by feeding this product.
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PMID:Toxic hepatic failure in newborn foals. 665 19


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