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 'binding' of IgE to particulate preparations derived from sonicated purified rat mast cells was measured by the blocking of PCA titrations of the supernatant solutions from incubations with such preparations. It was found that the PCA blocking reaction was inhibited by the addition of calcium ion to the incubations. The blocking reaction was strongly dependent on the pH of the incubations, being maximal at pH values lower than 5-0. The blocking reaction proceeded in a linear manner for at least 3 h provided that no more than 70 percent of the amount of IgE initially supplied had been removed by the particulate fraction. Only mast cell-derived preparations were capable of effecting PCA blocking.
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PMID:On the nature of the presumed receptor for IgE on mast cells. III. Kinetics of the blocking of the PCA reaction by cell-free particulate preparations from rat peritoneal mast cells and effect of pH and calcium concentration on the reaction. 0 50

This paper reports that the ionophore-induced slow-reacting substance (SRS) from mast cell tumor leukocytes is a member of a group of compounds called leukotrienes. Briefly, murine mastocytoma cells treated with calcium ionophore produced a SRS that caused guinea pig ileum to contract. This response could be reversed by an SRS antagonist, FPL 55712. Based on osotope incorporation experiments, spectrophotometry, and chemical degradation analyses, the SRS was identified. It is a cysteine-containing derivative of 5-hydroxy-7,9,11,14-icosatetraenoic acid, which was attached in a thioether linkage at C-6. The SRS was structurally related to previously identified epoxy and dihydroxy metabolites of arachidonic acid in leukocytes. The leukotrienes have the common feature of the presence of a conjugated triene. Leukotriene A is an intermediate in the formation of leukotriene B, and is proposed to be the precursor also of leukotriene C, the SRS chemically identified in this paper.
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PMID:Leukotriene C: a slow-reacting substance from murine mastocytoma cells. 4 Dec 40

The cyclic adenosine 3', 5'-monophosphate (cAMP) content of isolated unstimulated mast cells and the changes induced by a variety of pharmacologic, metabolic, and physical stimuli were studied. A modified bovine serum albumin density gradient purification method consistently provided mast cell preparations which were 95% or more pure, without apparent damage, and a 73% recovery of the mast cells applied to the gradients. The measured cAMP in unstimulated mast cells was high, a mean of 16 picomoles per million cells. Moderate agitation or contact with glass increased cAMP content about 2-fold. When calcium was omitted from the medium mast cell cAMP was markedly elevated; incremental increases in added calcium ion concentration from 1 muM to 1 mM caused a linear decrease in cAMP content. Theophylline (3 to 20 mM) caused a dose-related increase in mast cell cAMP content, approximately 2-fold at 20 mM theophylline. Epinephrine (0.01 to 1 mM) caused a modest, dose-related increase in cAMP. In the presence of theophylline, epinephrine increased cAMP levels equal to or greater than the sum of the effects of the agents used individually. The increase in cAMP induced by epinephrine was completely inhibited by 100 muM propranolol and partially inhibited by 10 muM propranolol, thus suggesting that a beta adrenergic receptor is involved. Prostaglandin E1 (PGE1) and histamine (in the presence of theophylline) also raised cAMP. Carbamylcholine (1 nM) lowered cAMP 38%; Atropine (0.1 mM) inhibited the decrease in cAMP induced by 1 nM carbamylcholine by 83% indicating that a muscarinic receptor is involved. In these homogeneous single cell suspensions, therefore, cholinergic and beta adrenergic agents have opposing effects on cAMP levels. Diazoxide (10 muM) and adenine (1 muM) caused 37 and 32% decreases in cAMP, respectively. The availability of highly purified mast cells and the identification of agents which either decrease or increase cAMP content allows a direct examination of the role of cAMP in histamine release.
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PMID:Modulation of cyclic AMP in purified rat mast cells. I. Responses to pharmacologic, metabolic, and physical stimuli. 4 63

Suspensions of rat mast cells were used to study the histamine-releasing actions of anaphylatoxins C3A and C5a in vitro. The peptides, derived from human or porcine complement proteins C3 and C5, were less potent than 48/80 but more potent than bradykinin in stimulating release of histamine from mast cells. The pattern of release resembled that of the anaphylactic release action, e.g. release was limited to less than 30 per cent of the cell histamine, the reaction was calcium-dependent and was potentiated by phosphatidyl serine. When C3a and C5a were added together to mast cell suspensions, the amount of histamine released was additive. Similarly, release by either peptide combined with bradykinin was additive. Histamine-releasing activity (as well as smooth muscle-stimulating activity) was abolished when the peptides were treated with pancreatic carboxy-peptidase B. Active or inactive peptides were bound by mast cells and addition of active C3a in combination with the inactive, des-arginine derivative, C3ai, resulted in partial inhibition of histamine release.
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PMID:Release of histamine from rat mast cells by the complement peptides C3a and C5a. 4 5

We have used ferritin-conjugated divalent and monovalent anti-Ig antibodies to study simultaneously, histamine secretion and the ultrastructural distribution and redistribution of Ig receptors on rat peritoneal mast cells. We conclude that (a) divalent anti-Ig is required for both receptor redistribution and for calcium-dependent degranulation and histamine release, (b) divalent anti-Ig induces patching and pinocytosis but not capping of Ig molecules, (c) neither capping nor pinocytosis are required for triggering and if clustering is necessary, then less than 10 Ig molecules are required per cluster, and (d) degranulation (and histamine release) is not an all or none response of the mast cell.
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PMID:Anti-immunoglobulin-induced histamine secretion by rat peritoneal mast cells studied by immunoferritin electron microscopy. 4 87

Inhibitors of mast cell membrane activation reduced histamine release from rat mast cells induced by dextran and phosphatidyl serine but not that induced by the calcium ionophore A23187. Such inhibitors included cromoglycate, an orally-active anti-allergic agent 3-(5-tetrazolyl)thioxanthone 10,10-dioxide, dibutyryl cyclic 3':5'-AMP, theophylline and dicumarol. Inhibitors of mast cell metabolism reduced both types of release and these included oligomycin, papevevime, and the two uncouplers of oxidative phosphorylation-alpha2,4-dinitrophenol and CCCP. Inhibition of histamine release from rat isolated peritoneal mast cells by either a mixture of dextran and phosphatidyl serine or the ionophore A23187 thus allows inhibitors of mast cell membrane activation to be distinguished from those affecting cell metabolism or the later stages of the secretory process.
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PMID:Differential histamine release by dextran and the ionophore A23187: the actions of inhibitors. 5 25

In the presence of L-cysteine, a selective and marked enhancement of the in vitro, immunologic release of slow reacting substance of anaphylaxis (SRS-A) from human peripheral leukocytes, sensitized monkey lung fragments, and sensitized guinea pig lung fragments was observed. In the rat, cysteine, but not sodium sulfide, enhanced the calcium ionophore (A23187)- induced release of SRS-A in vitro from mixed rat peritoneal cells and in vivo from the rat peritoneal cavity. Pretreatment of rats with cysteine also enhanced the IgGa-and anti-rat IgE-mediated release of SRS-A in vivo in the rat. These studies indicate a common biochemical mechanism involved in the formation and release of SRS-A from these different tissues and cells and further confirm the observation that the rat mast cell is not a major source of SRS-A in the rat.
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PMID:The effect of thiols on the immunologic release of slow reacting substance of anaphylaxis. II. Other in vitro and in vivo models. 5 39

The release of exogenous histamine was studied by superfusing brain slices following incubation with the radiolabeled amine. Histamine was released in a calcium-dependent way by 40 mM potassium. This release was high in hypothalamus and striatum and low in hippocampus and cortex. Compound 48/80, a mast cell histamine releasing agent, also induced histamine release, but only from hypothalamic tissue slices. It is suggested that the potassium-induced release of accumulated exogenous histamine is mainly from glial cells.
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PMID:Potassium-induced release of tritiated histamine from rat brain tissue slices. 5 72

Two morphologically different populations of rat peritoneal mast cells were observed in response to incubation with compound 48/80. Type 2 mast cells: cells with distinct contours exhibiting intracellular vacuoles containing altered granules and without signs of granule liberation; Type 3 mast cells: cells with indistinct countours and with varying number of granules liberated. The absence of calcium in the medium, high temperature (37 degrees C) in the presence as well as in the absence of calcium favoured type 2 versus the type 3 cells. The isolated mast cell population was less morphologically heterogeneous than the mixed cell population in response to the addition of compound 48/80. It is concluded that mast cells might release a great part of their histamine content without a concomitant liberation of the granule matrixes. The varying morphological pictures observed after incubating of mast cells with compound 48/80 is due to variable factors inherent to the experimental procedures.
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PMID:The histamine release process and concomitant structural changes in rat peritoneal mast cells. In vitro study on effects of compound 48/80 and the dependence of the process on cell preparation, temperature and calcium. 6 Nov 80

The stimulatory as well as the inhibitory capacity of alloantisera has been investigated with respect to rat mast cell functions. Alloantibody against alloantigens coded for by the major histocompatibility (H-1) gene region promoted histamine release from purified LEW mast cells. This process was found to be complement-independent but demonstrated an absolute requirement for calcium. Pretreatment of mast cells with anti-H-1 antisera in the absence of calcium markedly suppressed the IgE-dependent histamine release challenged either by antigen or by anti-IgE antibody. The alloantisera, however, did not interfere with the ability of compound 48/80-associated histamine liberation. Additionally, antibodies specific for H-1 antigens were highly effective in inhibiting the binding of IgE to the mast cell surface. Alloantisera absorbed with erythrocytes lost their capacity to block mast cell functions. Based on these data the possible ralationship between H-1 alloantigens and the IgE receptor on the mast cell surface is discussed.
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PMID:Stimulation and suppression of rat mast cell functions by alloantibodies. 6 80


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