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)

It had been reported by authors that salivary gland hormone, parotin, was composed with subunit (parotin-subunit) which showed molecular weight of 45,000, and that parotin-subunit had rabbit serum calcium decreasing activity and the cross reactivity with rabbit anti parotin serum. In the present report, in order to study physiological chemistry of parotin-subunit, the influence of parotin-subunit on serum Ca and 45Ca levels relating to calcium metabolism, the distribution of 131I-parotin-subunit, the effect of parotin-subunit, on adenyl cyclase-cyclicAMP system, the anabolic action, C-terminal amino acid sequence and sugar component of parotin-subunit were investigated. The results are summarized as follows: 1) The decrease of rabbit serum Ca after injection of parotin-subunit was related to change of Ca in stable bone, but not to inhibition of bone resorption. 2) A high concentrated localization of radioactivity of 131I-parotin-subunit was found in liver, kidney and spleen, and as much as 60% of administrated radioactivity was localized in liver at 5 min after the injection. The retention of radioactivity was found in testis, seminal vesicle, prostate, parotid gland and submaxillary gland. 3) Cyclic AMP level increased significantly in metaphysial bone, submaxillary gland and plasma after administration of parotin-subunit but in other organs with localized much radioactivities, the level did not changed. Parotin-subunit activated adenyl cyclase of particular fraction of metaphysial bone. 4) The C-terminal amino acid of parotin-subunit was Leu, and its C-terminal amino acid sequence was -Val-Ser-Ala-Thr- Leu-OH by digestion of carboxypeptidase A. 5) Parotin-subunit included 3.3% of sugar which consisted of amino sugar and uronic acid.
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PMID:[The study of physiological chemistry on a subunit of salivary gland hormone (2) (author's transl)]. 18 2

High m.w. [35S]heparin, labeled in vivo or in vitro, was released from purified rat mast cells by challenge with rabbit anti-rat F(ab')2, guinea pig anti-rat IgE, or calcium ionophore. The released and the residual heparin were isolated by Dowex 1 chromatography and were of comparable size by Sepharose 4B gel filtration. The majority of the released heparin was found by differential centrifugation to be granule-associated. Net percentage of mast cell heparin release, quantitated by metachromasia after isolation on Dowex 1 chromatography, correlated in a linear fashion with net percentage of histamine release, with heparin exhibiting a threshold requirement for onset of release. The correlation of histamine and high m.w. heparin release provides chemical support for the conclusion of others from ultrastructural studies that mast cell activation by immunologic means or by the calcium ionophore results in secretion of the whole granule.
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PMID:Immunologic release of heparin from purified rat peritoneal mast cells. 32 87

1. Isolated rat peritoneal mast cells incubated in Ca-free media for 2 h, with or without EDTA, and observed by phase-contact microscopy, became ;bubbled' in appearance when subsequently exposed to media rich in calcium (16-110 mM).2. Electron microscopy showed the response to be ;compound' exocytosis of the sort elicited by conventional mast cell secretagogues such as antigen (in sensitized cells) and 48/80.3. The response to Ca was inhibited by withdrawing glucose and adding dinitrophenol and was thus energy-dependent.4. Mg in similarly high concentration had no such stimulant effect on Ca-deprived cells, and excess Ca stimulated only after Ca deprivation.5. It is suggested that Ca deprivation may increase the permeability of the plasma membrane of the mast cell thereby allowing some Ca, when subsequently introduced in high concentration, to penetrate and activate exocytosis; and the results are considered further support for the postulated mediator function of Ca in stimulus-secretion coupling.6. Two inhibitory effects of calcium in high concentration were detected: (a) suppression of migration or expulsion of granules from the exocytotic pits within the cellular domain; and (b) diminished sensitivity to 48/80.
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PMID:Calcium and stimulus-secretion coupling in the mast cell: stimulant and inhibitory effects of calcium-rich media on exocytosis. 33 97

Lipid A-associated protein (LAP) isolated from preparations of bacterial lipopolysaccharides (LPS, endotoxins) has been demonstrated to initiate the release of amines from rat peritoneal mast cells. The release at low concentrations of LAP requires both cellular energy and calcium, and thus appears to be a true secretory response. At higher concentrations the release is independent of these variables. The time required for maximal response is approximately 10 to 15 min at 37 degrees C. The response appears to be a general property of Escherichia coli LAP preparations since LAP isolated from three serotypes of these organisms all have similar activity. On the basis of heat lability at 100 degrees C, the ability of LAP to initiate mast cell secretion appears to be independent of its ability mitogenically to stimulate murine B lymphocytes.
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PMID:Chemical and biological properties of a protein-rich fraction of bacterial lipopolysaccharides. II. The in vitro rat peritoneal mast cell response. 33 70

"Immunopharmacology" evolved as a field of research in its own right when it was appreciated that pharmacological methods can contribute to the understanding of immune mechanisms on the one hand or can be used to influence or even control immune reactions at all stages and levels. The best studied subjects of immunopharmacology are release and effects of the chemical mediator substances which are responsible for the reactions of effector cells thus causing the clinical symptoms in allergic or inflammatory diseases. In the type I allergic (anaphylactic) reactions the primary target cells are tissue mast cells or basophil granulocytes which discharge their granular contents upon interaction of immunoglobulin E fixed to their surface with the specific antigen or--in the anaphylactoid reaction--upon stimulation with an appropriate chemical substance (so-called histamine-liberator). In both cases the stimulus leads to an influx or intracellular shift from one compartment to another of calcium ions, which in turn trigger membrane fusion and degranulation. This process can vary from a physiological secretion (in the case of IgE-antigen-interaction) to a pathological cytolysis (in the case of high concentrations of activated complement components or other chemical histamine releasers). As long as it is secretory it is subject to vegetative and hormonal modulation and regulation, mainly by catecholamines and other substances which increase cellular cAMP levels or inhibit calcium fluxes. Although cholinergic stimuli under certain circumstances induce mast cell degranulation and histamine release no definite role has yet been established for cholinergic mechanisms in type I allergies. Type II (Cytotoxic) and type III (immune complex mediated) allergies share the complement requirement. As far as mast cells and basophils are involved in such reactions their sensitivity towards pharmacological modulators is comparable to reactions induced by chemical histamine releasers. Otherwise these types of allergic reactions are dominated by phenomena of general inflammation. In those mainly cytotoxic effects of lipases and hydrolases are involved. cAMP active agents have, therefore, only limited modulating effects and steroid hormones are more effective in inhibiting the acute lesions in type II and III allergies. Only during the last decade the involvement of chemical mediators in type IV (cellular immunity) allergic reactions has been appreciated. 26 different factors called lymphokines have been discovered and classified as mediators of cellular immune reactions. However, rather little is yet known about their chemical nature and about the influence of drugs on their production or action.
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PMID:Pharmacological aspects of immune reactions. 36 29

1 Cinnarizine, an inhibitor of calcium ion transport across smooth muscle cell membrane, has been shown to exert an anti-asthmatic effect in patients with chronic asthma. 2 It is postulated that antagonism to calcium ion transport across the mast cell membrane may cause the compound to have a pharmacological effect similar to sodium cromoglycate. 3 Cinnarizine is orally active and its therapeutic effect is demonstrated in a double-blind, cross-over, placebo controlled study. 4 Patient benefit was shown by a significant improvement in peak flow rate. A non-significant trend towards a reduction in symptomatic bronchodilator usage and a decrease in asthma symptom score was also shown. 5 It is concluded that cinnarizine could well prove to be the first of a new family of anti-asthmatic drugs offering a protective effect when taken systemically.
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PMID:Cinnarizine in the treatment of chronic asthma. 36 14

Weanling rats were given a low Ca (0.003%)/high P (0.64%) diet with and without vitamin D for periods up to 5 weeks. This was associated with hypocalcaemia, rachitic bone changes and increased bone resorption. These changes preceded the accumulation of large numbers of mast cells in long bone metaphyses. Mast cells did not increase in the epiphyses of long bones or in caudal vertebrae, tooth pulp, skin and other organs. A light and electron microscopic study showed that most mast cells had raised secretory activity, as evidenced by variability in the structure of granules and loss of granule contents, particularly in animals with the lowest serum calcium levels. It was not possible to relate the position of a mast cell to an area of active bone formation or resorption. The increase in mast cells might be related more to the maintenance of connective tissue integrity in areas of rapid bone remodelling.
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PMID:Low-calcium/high phosphorus rickets in rats. I. Mast cell changes. 53 Jul 54

Concanavalin A (Con A) covalently linked to Sepharose 4B beads induced localized degranulation of sensitized rat peritoneal mast cells in regions of contact between beads and cells. This degranulation was Ca2+ dependent and was not seen when sensitized mast cells bound to beads conjugated with a nonstimulating lectin, wheat germ agglutinin, or when unsensitized mast cells bound to Con A-Sepharose. The finding that sensitized mast cells which had adhered to Con A-Sepharose beads degranulated in regions of the cell away from the area of bead contact if exposed to soluble Con A excluded the possibility that the localized release was due to a redistribution of the IgE receptors or putative Ca2+ channels to the region of bead contact. The results suggest that, if an influx of Ca2+ is the mechanism for initiating mast cell degranulation, then the opening of Ca2+ channels in the plasma membrane of activated mast cells is a localized event and that Ca2+ acts locally within the cell to initiate exocytosis.
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PMID:Localized mast cell degranulation induced by concanavalin A-sepharose beads. Implications for the Ca2+ hypothesis of stimulus-secretion coupling. 56 56

In the presence of Ca2+ and Mg2+, the chemotactic fragment of C5, the synthetic chemotactic oligopeptide formyl-methionyl-leucyl-phenyl-alanine, and the ionophore A23187 aggregated human neutrophils. Aggregation induced by the two chemotactic factors was transient and reversed within 2 to 4 minutes after exposure; aggregation induced by A23187 was sustained and continued to increase over 15 minutes. In the absence of the bivalent cations, none of these three agents aggregated the cells. If bivalent cations were added after cell contact with a chemotactic factor, aggregation was detected after, but not before, addition of the cations. Under these conditions, the magnitude of the aggregation response was sharply reduced: cells preincubated with a chemotactic factor for longer than 2 to 4 minutes aggregated minimally after addition of bivalent cations. Moreover, cells preincubated with a chemotactic factor for 4 minutes, exposed to bivalent cations, and then rechallenged with the same chemotactic factor also showed a minimal aggregation response, ie, the cells were "desensitized" to the original stimulus. However, cells desensitized to one of the chemotactic factors still aggregated prominently when exposed to the other chemotactic factor or to A23187. Cells could not be desensitized to the ionophore A23187. Desensitization of the neutrophil aggregation response closely resembles desensitization of mast cell and leukocyte degranulation. Degranulation and aggregation appear to be closely related cellular responses to immunologic stimuli. Both responses may reflect alterations in surface membrane permeability to bivalent cations and/or changes in surface membrane adhesiveness to other biologic membranes.
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PMID:Desensitization of the neutrophil aggregation response to chemotactic factors. 71 43

Eosinophil chemotactic factor (ECF), previously thought to be primarily associated with human basophils and mast cells, could be released from human neutrophils (PMN) and eosinophils but not lymphocytes by the calcium ionophore A23187. Release of ECF from PMN was time and dose-dependent. Like antigen-induced, basophil-derived ECF, PMN-derived ECF had a high selectivity for eosinophils as determined by differential counts of migrating cells and by deactivation studies. Chromatographic analysis of PMN-derived ECF on Sephadex G-25 showed an elution pattern very similar to that of basophil-derived ECF. With rat peritoneal cells, it was possible to show that mast cells as well as mast cell-depleted cell preparations could be induced to release an ECF that appears to be similar or identical to human ECF. These findings suggest that ECF may play a role in inflammatory processes involving cells other than basophils and mast cells.
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PMID:Eosinophil chemotactic factor (ECF). I. Release from polymorphonuclear leukocytes by the calcium ionophore A23187. 77 63


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