Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Guinea-pigs kept on a diet deficient in vitamin C showed, after 3 weeks, a marked decrease of ascorbic acid in brain and blood leucocytes as well as of the activity of alkaline phosphatase in blood plasma. Pair-fed animals did not exhibit these changes. The alpha-methyl-p-tyrosine (alpha MpT)-induced diminution of noradrenaline in the hypothalamus and the rest of the brain was attenuated in pair-fed animals, but restored in guinea-pigs deficient in ascorbic acid. The cerebral noradrenaline content (without administration of alpha MpT) showed a decrease in both pair-fed and ascorbic acid deficient animals. The noradrenaline of the heart exhibited a similar tendency. The alpha MpT-induced dopamine decrease in the striatum of ascorbic acid deficient animals was attenuated and the dopamine content (without alpha MpT administration) decreased. Pair-fed animals showed a similar tendency. The striatal concentration of homovanillic acid (HVA) was diminished in both pair-fed and ascorbic acid deficient guinea-pigs. The cerebral content of 5-hydroxyindoleacetic acid showed a decrease in pair-fed as well as in ascorbic acid deficient animals. It is concluded that ascorbic acid deficiency enhances the turnover of brain noradrenaline, whereas under-nutrition without ascorbic acid deficiency (pair-feeding) diminishes the turnover of cerebral noradrenaline, 5-hydroxytryptamine and striatal dopamine.
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PMID:Cerebral monoamine metabolism in guinea-pigs with ascorbic acid deficiency. 0 59

Out of other functions performed by vitellaria in digenetic trematodes, their role in the formation of shell globules and shell membrane of the capsule, as well as in the excretion of iron with the help of vitamin C is very important. The present histochemical work shows the localization of certain enzymes in different parts of the reproductive system of ten species of trematodes viz.: Neopronocephalus triangularis Mehra, 1932; Glossimetra orientalis Mehra, 1937; Orientodiscus lobatus Srivastava, 1938; Eumegacetes artemii Mehra, 1935; Ganeo tigrinus mehra et Negi, 1928; Encyclometra caudata Dollfus, 1928; Thapariella udaipurensis Gupta and Sharma, 1970; Paradistomoides indicum Narain et Das, 1929; Patagifer wesleyi Verma, 1936; Proalarioides tropidonotus Vidyarthi, 1937 and indicates their functional significance. The hydrolytic enzymes (alkaline phosphatase, acid phosphatase, 5-nucleotidase and ATPase) are suggestive of their involvement in the uptake of certain nutrients, glycogen and lipoprotein being very significant among others. The four enzymes could also be detected in testes, ovary, uterus, cirrus sac and egg shell. The possible functional significance of each enzyme has been discussed.
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PMID:Histochemical studies on the distribution of alkaline phosphatase, acid phosphatase, 5-nucleotidase and ATPase in various reproductive tissues of certain digenetic trematodes. 18 33

The influence of high intake of vitamin C in the young growing rats under administration of nickel sulphate in toxic doses has been studied. Ingestion of nickel sulphate depresses the growth rates of rats, alters the vitamin C status in different tissues, inhibits certain enzymes of vitamin C metabolism and changes the activities of alkaline phosphatase and succinic dehydrogenase in the liver and kidney tissues. The acid phosphatase activity of liver, kidney and brain tissues of rats and glucose-6-phosphatase activity in liver, and serum GOT activity were stimulated, with reduction in the in the liver GOT activity. There is stimulation in the activities of rat brain inorganic pyrophosphatase and cholinesterase. Kidney tissues of rats were found to be more susceptible towards nickel toxicity as compared to the hepatic tissues in respect of morphological alterations. There is almost no alteration in the hepatic lipid composition. Administration of vitamin C in high doses to rats fed nickel salts in toxic doses can restore not only the growth rates but also certain enzyme activities to a significant extent.
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PMID:Biochemical studies on nickel toxicity in weanling rats -- influence of vitamin C supplementation. 23 Oct 18

Brush border sucrase and alkaline phosphatase activities are considerably enhanced in the intestine of ascorbic acid deficient guinea-pigs. Similar increase in the uptake of D-glucose and L-alanine also occurs in chronic vitamin C deficiency. However the permeability of D-glucose and L-alanine in the intestine of animals fed with large doses of vitamin C is severely depressed, with a reduction in the levels of sucrase and alkaline phosphatase activities.
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PMID:Effect of chronic hypo and hypervitaminosis C on the brush border enzymes and the intestinal uptake of glucose and alanine. 47 73

The adrenals of rabbits on a cholesterol-rich diet for 35 days show histopathological changes, a marked increase in weight and a lowering in the ascorbate content. A focal increase in the neutral lipid and cholesterol content was noted mostly in the inner cortical zones; and a characteristic acid phosphatase-positive pattern in areas of infiltrating cells, and an alkaline phosphatase-positive reaction in heterophils in the infiltrated areas. Electron microscopy confirmed that the zona glomerulosa cells were relatively normal in hypercholesterolaemic rabbits, while necrosis and fibrosis were very obvious in the inner two zones. The cellular infiltrate was shown to consist of large, granular mononuclear cells, heterophils, eosinophils, stromal phagocytes, lymphocytes and plasma cells. The possibility that the reaction was of an immunological nature is considered. The morphology of the adrenals of rabbits which were on a cholesterol-rich diet for 35 days and on a normal diet for 6 weeks afterwards, was indistinguishable from that of those rabbits killed after 35 days on a cholesterol-rich diet.
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PMID:The adrenal cortex in hypercholesterolaemic rabbits: histochemical and electron microscopical changes. 65 31

Intramuscular injections of testosterone propionate (Perandren, CIBA) at a dose level of 2.5 mg per day for 10 days into adult female parakeet caused an increment of differentiated follicles in the ovary. The histological study of the testosterone treated oviduct of the bird showed well developed villi with a significant number of tubular glands particularly in the middle and distal parts of the oviduct. The high level of alkaline phosphatase activity and ascorbic acid concentration in the distal part of the oviduct in treated birds probably increase the power of hatchable eggs which has a close relationship with the enzyme and vitamin C concentration in the uterus. The testosterone treatment causes a marked depletion of granulosal vitamins from ovary but augments the ascorbate mobilization in the thecal region to a very great extent probably due to more LH secretion from the pituitary.
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PMID:Histological and histochemical studies on the female reproductive system of rose-ringed parakeet (Psittacula krameri) after testosterone propionate treatment. 81 Oct 44

The case is reported of a 29-year-old previously healthy female patient who developed the typical clinical picture of scurvy eight months after changing to a diet exclusively containing cooked cereals. Serum levels of B12, folic acid, and calcium were lowered and the alkaline phosphatase was slightly raised due to the dietary lack of vitamins A, D, B12 and folic acid. No clinical signs of these deficiencies could be observed. Addition of vitamin C to this diet resulted in complete cure in a matter of days. Signs and symptoms of scurvy are discussed in the light of the recent literature. This rare disease is particularly worth considering if one of the following situations is encountered: hemorrhages in the skin, muscles, joints or mucous membranes without apparent cause; therapy-resistant ulcers of mucous membranes in elderly patients; Sicca syndrome and/or wounds exhibiting poor healing.
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PMID:[Scurvy in an adult]. 91 80

Fragments of cancellous and cortical bone from human maxilla and mandible were cultured by the explant technique. Cells isolated by trypsinization of primary cultures were characterized as osteoblasts on the basis of intracellular alkaline phosphatase activity, the constituents of the extracellular matrix, and response to human parathormone (PTH). In culture, the osteoblasts often gave rise to superposed clumps of large cells whose cytoplasm contained endoplasmic reticulum, numerous mitochondria, vacuoles, and a dense network of intermediate filaments, often at the level of the plasma membrane. In the presence of vitamin C and 1,25-dihydroxyvitamin D3, the osteoblasts produced an extracellular matrix composed of collagen type I and various non-collagenous proteins, including osteocalcin. Biochemical test results were comparable to those reported for osteoblasts of other origins (rat calvaria, human iliac crest), and namely elevated intracellular alkaline phosphatase activity and cAMP accumulation in response to stimulation by human PTH (1-34). Osteoblasts isolated in this manner were cultured in the presence of pure titanium disks to determine the effects of exposure to this metal. Electron microscopy revealed few significant differences in cell growth and specific enzyme activity compared to control osteoblasts grown on plastic dishes, reflecting the excellent biologic and biochemical relationship between the osteoblasts and pure titanium. This experimental system thus appears suitable for biocompatibility studies, and in particular, evaluation of dental implants.
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PMID:Characterization of endosteal osteoblasts isolated from human maxilla and mandible: an experimental system for biocompatibility tests. 136 48

The MC3T3-E1 mouse calvaria-derived cell line has been used to study the role of collagen synthesis in osteoblast differentiation. MC3T3-E1 cells, like several previously characterized osteoblast culture systems, expressed osteoblast markers and formed a mineralized extracellular matrix only after exposure to ascorbic acid. Mineralization was stimulated further by beta-glycerol phosphate. Ultrastructural observations indicated that the extracellular matrix produced by ascorbic acid-treated cells was highly organized and contained well-banded collagen fibrils. Expression of osteoblast markers followed a clear temporal sequence. The earliest effects of ascorbic acid were to stimulate type I procollagen mRNA and collagen synthesis (24 h after ascorbate addition), followed by induction of alkaline phosphatase (48-72 h) and osteocalcin (96-144 h) mRNAs. Procollagen mRNA, which was expressed constitutively in the absence of ascorbate, increased only twofold after vitamin C addition. In contrast, alkaline phosphatase and osteocalcin mRNAs were undetectable in untreated cultures. Actions of ascorbic acid on osteoblast marker gene expression are mediated by increases in collagen synthesis and/or accumulation because (1) parallel dose-response relationships were obtained for ascorbic acid stimulation of collagen accumulation and alkaline phosphatase activity, and (2) the specific collagen synthesis inhibitors, 3,4-dehydroproline and cis-4-hydroxyproline, reversibly blocked ascorbic acid-dependent collagen synthesis and osteoblast marker gene expression.
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PMID:Relationship between collagen synthesis and expression of the osteoblast phenotype in MC3T3-E1 cells. 137 31

We examine clonal murine calvarial MC3T3-E1 cells to determine if they exhibit a developmental sequence similar to osteoblasts in bone tissue, namely, proliferation of undifferentiated osteoblast precursors followed by postmitotic expression of differentiated osteoblast phenotype. During the initial phase of developmental (days 1-9 of culture), MC3T3-E1 cells actively replicate, as evidenced by the high rates of DNA synthesis and progressive increase in cell number, but maintain a fusiform appearance, fail to express alkaline phosphatase, and do not accumulate mineralized extracellular collagenous matrix, consistent with immature osteoblasts. By day 9 the cultures display cuboidal morphology, attain confluence, and undergo growth arrest. Downregulation of replication is associated with expression of osteoblast functions, including production of alkaline phosphatase, processing of procollagens to collagens, and incremental deposition of a collagenous extracellular matrix. Mineralization of extracellular matrix, which begins approximately 16 days after culture, marks the final phase of osteoblast phenotypic development. Expression of alkaline phosphatase and mineralization is time but not density dependent. Type I collagen synthesis and collagen accumulation are uncoupled in the developing osteoblast. Although collagen synthesis and message expression peaks at day 3 in immature cells, extracellular matrix accumulation is minimal. Instead, matrix accumulates maximally after 7 days of culture as collagen biosynthesis is diminishing. Thus, extracellular matrix formation is a function of mature osteoblasts. Ascorbate and beta-glycerol phosphate are both essential for the expression of osteoblast phenotype as assessed by alkaline phosphatase and mineralization of extracellular matrix. Ascorbate does not stimulate type I collagen gene expression in MC3T3-E1 cells, but it is absolutely required for deposition of collagen in the extracellular matrix. Ascorbate also induces alkaline phosphatase activity in mature cells but not in immature cells. beta-glycerol phosphate displays synergistic actions with ascorbate to further stimulate collagen accumulation and alkaline phosphatase activity in postmitotic, differentiated osteoblast-like cells. Mineralization of mature cultures requires the presence of beta-glycerol phosphate. Thus, MC3T3-E1 cells display a time-dependent and sequential expression of osteoblast characteristics analogous to in vivo bone formation. The developmental sequence associated with MC3T3-E1 differentiation should provide a useful model to study the signals that mediate the switch between proliferation and differentiation in bone cells, as well as provide a renewable culture system to examine the molecular mechanism of osteoblast maturation and the formation of bone-like extracellular matrix.
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PMID:Distinct proliferative and differentiated stages of murine MC3T3-E1 cells in culture: an in vitro model of osteoblast development. 141 87


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