Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The ability of thapsigargin and thapsigargicin to activate mast cells and leukocytes has been investigated. The thapsigargin-induced histamine release from rat peritoneal mast cells was found to be dependent on the concentration of thapsigargin, the purity of the mast cell preparations, and the number of mast cells in suspension. Thapsigargin induced histamine release from human basophil leukocytes. Thapsigargin induced beta-glucuronidase and lysozyme release from human neutrophil leukocytes. Thapsigargin caused a release of histamine from mesentery, lung, and heart mast cells of the rat, but only to a minor extent from the corresponding guinea-pig cells. Thapsigargicin induced histamine release from mesentery, lung, and heart mast cells of the rat at concentrations from 0.1 microM but provoked only a release from the corresponding guinea-pig cells in the concentration-range 0.16 to 1.6 microM. Thapsigargin increased the cytoplasmic free calcium level in intact human blood platelets at concentrations from 3.0 nM.
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PMID:The ability of thapsigargin and thapsigargicin to activate cells involved in the inflammatory response. 241 28

The demonstration of a specific receptor for IgE on non-mast cell or basophil leucocytes, such as mononuclear phagocytes, eosinophils and platelets, suggests that these cells may participate directly in immunological disorders of allergy. In this study, inhibition by nedocromil sodium of IgE-dependent activation of human alveolar macrophages, blood monocytes and platelets was investigated. Nedocromil sodium produced an inhibition of IgE-mediated generation of cytotoxic molecules from monocytes and platelets together with a concomitant inhibition of their oxidative metabolism, measured by chemiluminescence. In addition, nedocromil sodium reduced the ability of alveolar macrophages to synthesise and release mediators, estimated by beta-glucuronidase activity. Furthermore, nedocromil sodium inhibited the abnormal response to aspirin of platelets from aspirin-sensitive asthmatics at therapeutic concentrations. These studies confirm that nedocromil sodium acts on a cell compartment other than the classical mast cell population in IgE-dependent allergy and asthma.
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PMID:Nedocromil sodium inhibition of IgE-mediated activation of human mononuclear phagocytes and platelets from asthmatics. 254 66

The demonstration of a specific receptor for IgE on nonmast cell or basophil leukocytes, such as mononuclear phagocytes, eosinophils, and platelets, suggests that these cells may participate directly in immunological disorders of allergy. Thus, a full understanding of the mode of action of antiallergic or antiasthma drugs must take into account their activity on these nonmast cell leukocytes. Consequently, inhibition by nedocromil sodium of IgE-dependent activation of human alveolar macrophages, blood monocytes and platelets, was investigated. This compound induced an inhibition of the IgE-mediated generation of cytotoxic molecules from monocytes and platelets, together with a concomitant inhibition of their oxidative metabolism, measured by chemiluminescence, and a reduction of the potential ability of alveolar macrophages to synthesize and release mediators, estimated by lysosomal beta-glucuronidase activity. These observations confirm the hypothesis that nedocromil sodium acts on a cell compartment other than the classical mast cell population, in IgE-dependent allergy and, more particularly, in asthma.
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PMID:Inhibition by nedocromil sodium of IgE-mediated activation of human mononuclear phagocytes and platelets in allergy. 282 42

The effects of zinc acexamate on stress and reserpine ulcers as well as on gastric mast cells degranulation and membrane stability were evaluated in the rat. Zinc acexamate (100 mg/kg) has demonstrated an inhibitory effect on cold-restraint stress and reserpine-induced ulcer in a dose-dependent manner. Pretreatment of rats, prior to cold restraint stress, reduced gastric mast cell degranulation. Zinc acexamate (10(-4) M) inhibits Triton X-100 release of beta-glucuronidase in isolated hepatic lysosomes. These observations suggest that ulcer protective actions of zinc acexamate may be exerted in part through enhancing gastric mucosal resistance by stabilizing biological membrane integrity.
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PMID:Anti-ulcer and membrane stabilizing actions of zinc acexamate. 357 22

The mast cell, located at mucosal surfaces and surrounding venules, is uniquely positioned to respond rapidly to insults to the host by mediating the development of a wide-ranging inflammatory response. Activaton of the mast cell releases preformed granule-associated chemical mediators and generates de novo biologically active materials. The properties of the mast cell mediators permit development of both acute and prolonged inflammatory responses. the immediate response is characterized by edema and the delayed response by leukocyte infiltration and vascular damage. the mast cell mediators responsible for these inflammatory events are characterized functionally. The vasoactive/smooth muscle reactive mediators include preformed histamine and serotonin and newly-generated platelet activating factor, slow reacting substance of anaphylaxis and prostaglandins. Chemotactic mediators include eosinophil-selective ECF-A and ECF-oligopeptides, neutrophil-selective NCF, and lipid chemotactic mediators with broad specificity. These factors induce directed migration and localization of leukocytes. The mast cell releases the structural proteoglycan, heparin, which is anticoagulant and inhibits complement. Released mast cell enzymes include chymotryptic and tryptic proteases, arylsulfatase, beta-glucuronidase, and hexosaminidase. The proteolytic enzymes may activate inflammatory pathways while the others degrade ground substance. The capacity of the mast cell to enhance vascular permeability, to cause the influx of regulatory or inflammatory leukocytes, and to provide a variety of active enzymes permits regulation of inflammatory events at the site of tissue injury.
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PMID:The lung mast cell: its physiology and potential relevance to defense of the lung. 610 56

Purified mature rat peritoneal mast cells, on exposure to zymosan or latex beads, phagocytize these particles, although less efficiently than macrophages. During phagocytosis, histamine, beta-glucuronidase, and eosinophil chemotactic factor are released from mast cells in a time-, temperature- and dose-dependent fashion. Complement components, cytochalasin B (5 microgram/ml), and indomethacin (10-6M), enhanced mediator release, whereas compound BW 755C (20 microgram/ml), a cyclooxygenase and lipoxygenase inhibitor of arachidonate metabolism, totally abolished this process. Phagocytosis of mast cell thus activates intracellular mechanisms that closely resemble those observed with other phagocytic cells. These observations add a new perspective to the role of mast cells in inflammatory events.
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PMID:Release of mediators from purified rat mast cells during phagocytosis. 618 56

N-Formylmethionyl-leucyl-phenylalanine (FMLP) is a synthetic chemotactic peptide which induced beta-glucuronidase and lysozyme release from human neutrophils treated with cytochalasin B. FMLP-releasing effects were rapid and dose dependent. Unlike other secretagogues of neutrophils (e.g., zymosan and immune complexes), FMLP secretory activity was not modulated by acetylcholine, which by itself did not release lysosomal enzymes from human neutrophils. Isolated rat mast cells did not respond to FMLP, which has been demonstrated to release histamine from human neutrophils. Two markers of rat mast cell secretory granules, histamine and beta-glucuronidase, were assayed, but the results were negative for both. In the same experimental conditions, 48/80 released histamine and the enzyme: the ratio of the net percentage release of beta-glucuronidase to the net percentage release of histamine was congruent 0.4.
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PMID:N-Formylmethionyl-leucyl-phenylalanine: Different releasing effects on human neutrophils and rat mast cells. 619 52

The recovery of mast cells in adult rats after depletion induced by polymyxin-B has been studied. At days 17-18 after depletion the number of identifiable mast cells in the peritoneal fluid reached 3 X 10(6) cells/rat. Mast cell granule constituents such as histamine, heparin, mast cell protease and beta-glucuronidase increased steadily during the observation period, whereas the amount of N-acetyl-beta-glucosaminidase decreased during the first 2 weeks and was thereafter constant. At 2 weeks after depletion the peritoneal mast cells were biochemically restored. From 14 to 34 days (end of experimental period) cell growth occurred with a simultaneous accumulation of the various mast cell granule constituents.
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PMID:Mast cell restoration. A study of the rat peritoneal mast cells after depletion with polymyxin B. 626 1

Mast-cell-depleted rat peritoneal exudate cells have been shown to differentiate into pure mast cell cultures when placed in a special medium containing 15% horse serum and 20% L-cell supernatants. In the present communication, the changes that occur within the cells during culture are examined by several parameters. Prior to culture, the cells resemble mononuclear phagocytes morphologically. During culture, their total cell volume and cytoplasmic mass increase, and they develop metachromatic, alcian blue and later on safranin-positive cytoplasmic granules. Proliferation of the cells, as shown by 3H-thymidine incorporation, is optimal between days 3 to 11, and is decreased by changing the composition of the medium or by adding high concentrations of histamine (greater than 10-6M) and heparin (greater than 50 millimicron/ml). By cytochemical staining and by analysis of subfractionated cellular components, eosinophil chemotactic factor (ECF), histamine, beta-glucuronidase, alpha-naphthyl acetate esterase and myeloperoxidase are demonstrated, mostly within the granules. The findings suggest a close morphological and functional relationship between peritoneal mast cell precursors and mononuclear phagocytes.
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PMID:Studies on the in vitro development of rat peritoneal mast cells. 626 48

Rat mast cell granules contain a spectrum of enzymes as established by histochemical techniques and subcellular fractionation. However, 35% of the beta-glucuronidase, 30% of the beta-D-galactosidase, 14% of the beta-hexosaminidase and all of the acid phosphatase is not available for immunologic release from purified rat serosal mast cells, suggesting the presence of nonsecretory lysosomes containing these acid hydrolases. On the other hand, immunologic release of the majority of chymase, beta-hexosaminidase, beta-glucuronidase, beta-D-galactosidase, and arylsulfatase A occurs in parallel with histamine and thereby localizes these substances to the rat mast cell secretory granule. A molecular model of the secretory granule in the resting mast cell can now be constructed in which heparin proteoglycan is the granule matrix to which chymase and probably other proteins are ionically bound. Inhibition of chymase by serotonin stored in its active site and of chymase and acid hydrolases by their interaction with heparin probably occurs. Histamine is stored by ionic linkage to carboxyl groups of protein and heparin. Micromolar amounts of heparin glycosaminoglycans, histamine, serotonin, chymase, beta-D-hexosaminidase, beta-glucuronidase, and arylsulfatase A in secretory granules of 10(6) mast cells are 0.7--1.3 x 10(-3), 70--220 x 10(-3), 0.9--28 x 10(-3), 0.2--0.5 x 10(-3), 0.9--2.7 x 10(-6), 0.1--0.3 x 10(-6) and less than 8 x 10(-6), respectively. In addition, the total protein available for calcium ionophore-induced release from 10(6) rat mast cells is about 60 microgram, indicating that less than 50% of the granule protein can be accounted for. Recognition that mast cell secretory granules contain acid hydrolases indicates that they are modified lysosomes; their special intracellular and extracellular functions are dictated by the associated novel constituents and the stimulus for activation.
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PMID:Enzymes of the mast cell granule. 677 34


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