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)

Previous studies have shown that nasal allergen provocation leads to dose-dependent increases of inflammatory mediators, e.g. histamine, kinins, LTC4 and PGD2 in nasal lavages. To investigate further the interaction of these mediators, a titration study with intranasal bradykinin (Bk) application (maximal dose 100 nmol/nostril) and consecutive lavage were performed in eight grass-pollen-allergic patients out of season, and five controls. The nasal lavages were analysed for albumin, N-alpha-tosyl-L-arginine methyl ester (TAME) esterase activity, histamine, 9 alpha,11 beta-PGF2, and LTC4. The clinical reactions were measured with a subjective symptom score. A dose-dependent elevation of albumin was found which was significantly higher in patients with allergic and non-allergic rhinitis compared with normal volunteers. TAME-esterase activity also increased in relation to the dosage of Bk given without significant difference between the various groups. No influence on histamine, LTC4 and 9 alpha,11 beta-PGF2, release (PGD2 metabolite) was seen. Short-lasting clinical symptoms like irritation, sneezing, and obstruction were noticed after the two highest Bk dosages (10 and 100 nmol). We conclude that intranasally applied Bk induces a dose-dependent plasma leakage into the nasal cavity, which is significantly higher in patients with seasonal allergic rhinitis out of season compared to normals. Bk does not seem to affect the mast cell since histamine, LTC4 and 9 alpha,11 beta-PGF2 levels do not alter. The ability to induce relevant symptoms of rhinitis provides strong support for the hypothesis that kinins may be important mediators of inflammatory disorders of the upper airways.
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PMID:Nasal challenge studies with bradykinin: influence upon mediator generation. 191 65

Using our animal model of synovial mast cell-mediated arthritis in rats, we tested the effects of 3 nonsteroidal antiinflammatory drugs (NSAIDs) (aspirin, indomethacin, and ketoprofen) and an H1 and an H2 histamine receptor antagonist (diphenhydramine and cimetidine, respectively) on synovial and dermal mast cell-induced vasopermeability. Drug effects were assessed by quantifying the leakage of radiolabeled albumin into tissues following specific antigen-initiated activation of passively sensitized dermal and synovial mast cells. The 3 NSAIDs tested had different effects on synovial and dermal mast cell-induced vasopermeability. Aspirin and indomethacin significantly increased dermal and synovial plasma exudation (P less than or equal to 0.008). Ketoprofen decreased dermal (P = 0.015), but had no effect on synovial, vascular exudation. Complete histamine H1 and H2 receptor blockade with diphenhydramine and cimetidine, respectively, substantially decreased (P less than or equal to 0.0008), but did not completely inhibit, dermal and synovial mast cell-induced vasopermeability. However, the addition of indomethacin to the combined antihistamine regimen resulted in an increase in the leakage of the radiolabel into skin and synovium (back to control levels), despite the complete blockade of H1 and H2 receptors. Results of experiments with antihistamines and indomethacin suggest that mediators other than histamine are involved in synovial mast cell-induced inflammation. Furthermore, the differential response to ketoprofen indicates that the specific antigen-stimulated mediator release profiles of dermal and synovial mast cells are different. Our finding of enhanced synovial vascular leakage in animals treated with some NSAIDs, and no such effect by other NSAIDs, perhaps explains in part the diverse effects of these agents in humans with arthritis.
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PMID:In vivo effects of nonsteroidal antiinflammatory drugs on rat skin and synovial mast cell-induced vasopermeability. 199 13

The effect of chronic dietary antigen challenge on the intestine was examined in sensitized rats. Three groups of Hooded-Lister rats were studied: animals sensitized to egg albumin; sham-sensitized animals; and unmanipulated controls. In sensitized rats, serum immunoglobulin E titers to egg albumin were greater than or equal to 1:64, whereas control and pair-fed rats showed no response. Sensitized rats received egg albumin 1 mg/ml in drinking water and rat chow ad libitum. Pair-fed animals also received egg albumin but were pair-fed with sensitized animals. Controls received water and rat chow ad libitum. Chronic antigen challenge resulted in reduced food intake and weight gain in sensitized animals. When the rats were killed after 9 days of antigen exposure, proximal intestine from experimental animals showed decreased disaccharidase activity, brush-border microvillus surface, area, and villus height. Crypt depth and enterocyte migration rate were increased. Mucosal mast cell involvement was suggested by mast cell proliferation, evidence of mast cell degranulation, and increased serum rat mast cell protease II levels. At the time of death, only sensitized jejunum demonstrated an increase in short-circuit current in Ussing chambers in response to antigen challenge. The findings indicate that chronic antigen exposure leads to intestinal injury, reduced food intake, and diminished weight gain.
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PMID:Intestinal anaphylaxis in the rat. Effect of chronic antigen exposure. 218 52

A prospective study compared the levels of inflammatory mediators in nasal lavages from noninfected, asymptomatic subjects with the mediator content of lavages from the same subjects during naturally occurring rhinovirus colds. Samples were obtained from 16 subjects who experienced natural colds that could be attributed to rhinovirus infections. Kinin levels during symptomatic colds were significantly elevated (P less than .01) compared with those measured when the subjects were noninfected and asymptomatic. Increases in kinins correlated with increased vascular permeability, as monitored by increased concentrations of albumin in lavages. In contrast, histamine levels in nasal lavages were not increased during symptomatic infections, suggesting that mast cell and basophil activation does not occur during rhinovirus colds. These data confirm and extend observations made during experimentally induced rhinovirus infections to the natural disease and are consistent with the hypothesis that kinins may play a role in the pathogenesis of symptomatic rhinovirus infections.
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PMID:Kinins are generated in nasal secretions during natural rhinovirus colds. 229 43

Dinitrophenyl (DNP) derivatives of various molecular weights were tested for their ability to elicit ocular anaphylaxis after topical application to the eye of immunized animals. Adult male Sprague-Dawley rats were immunized by intraperitoneal injection of DNP-Ascaris suum extracts and alum and were then skin-tested with DNP-bovine serum albumin on day 13 post-immunization to assess their sensitivity to the DNP hapten. On day 14, animals were challenged topically with DNP derivatives in one eye; PBS was applied to the contralateral, control eye. Animals were evaluated clinically, and ocular tissues were processed for histologic evaluation. The compounds used for topical ocular challenge included the DNP derivative of egg albumin (MW 43,500 D), soybean trypsin inhibitor (MW 20,080 D), insulin (MW 5733 D), B-chain insulin (MW 3496 D), and lysine (MW 478 D). Only di-DNP-lysine elicited clinical signs of redness, edema, and tearing and histologic evidence of mast cell degranulation. None of the other compounds, tested in solutions of either equal numbers of milligram per milliliter or equimolar concentrations, elicited ocular anaphylaxis after topical application. A compound of low molecular weight, less than 3496, is needed to elicit ocular anaphylaxis when applied topically.
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PMID:Penetrating the conjunctival barrier. The role of molecular weight. 230 28

Myofiber injury-repair was studied in the rat following blunt trauma to the lower leg in order to understand how the inflammatory and regenerative responses of muscles are altered when myofiber rupture is accompanied by bleeding and clotting reactions. A contusion injury to the muscles of the lower hindlimb of the rat was induced by applying an impact force of 4.7 N-m/cm2 to one leg. The gastrocnemius and soleus muscles were removed bilaterally and evaluated by histochemical and immunohistochemical techniques to document myofiber, vascular, and connective tissue alterations for several days following insult (6-120 hr). A significant increase in wet weight of the gastrocnemius muscle was noted 24 hr postinjury as fluid accumulation and bruising were evident in the muscles resulting from bleeding and inflammation. Vascular disruption was confirmed by the localization of some plasma constituents (fibrinogen, albumin, and complement C3) throughout the interstitial space and even inside some of the damaged myofibers. Inflammation was present and persisted for 5 days as evidenced by continued mast cell degranulation and increased vascular permeability. Using antibodies to identify specific proteoglycans which appear or disappear at various times during muscle regeneration, muscle repair could be followed. The repair process required approximately 10 days for restoration of morphologically intact myofibers. Thus, myofiber repair processes appear to be maintained even after disruption of the vascular system and ischemia following blunt trauma.
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PMID:Extracellular matrix changes following blunt trauma to rat skeletal muscles. 230 15

This study examined the electrophysiological responses to antigen and to various stimuli in jejunal mucosa from rats sensitized to egg albumin with alum and pertussis adjuvants. Luminal antigen caused an immediate increase in short-circuit current, a measure of net ion transport, which was one of three different patterns. All were inhibited by the chloride channel blocker diphenyl-2-carboxylate, by chloride-free buffer, and by doxantrazole, a mast cell stabilizer. Depending on the pattern, the histamine-1 antagonist diphenhydramine, the 5-hydroxytryptamine-2 antagonist ketanserin, and the cyclooxygenase inhibitor piroxicam also reduced the responses. A neural component was indicated by inhibition of the responses to luminal antigen by the neurotoxin tetrodotoxin and by neonatal capsaicin treatment, which depletes substance P-containing nerves. In the absence of antigen, histamine and substance P caused increases in short-circuit current; the magnitude of these changes was significantly greater in tissues from sensitized animals than in controls. These data suggest that sensitization itself may result in hypersecretory responses to some inflammatory mediator and neurotransmitter substances.
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PMID:Allergic reactions of rat jejunal mucosa. Ion transport responses to luminal antigen and inflammatory mediators. 234 44

Alterations in myoelectric and motor activity are important features of food protein-induced intestinal anaphylaxis. To determine the mediator(s) involved, rats were sensitized by injection of egg albumin (10 micrograms ip), and controls were sham sensitized with saline. Fourteen days later the contractility of longitudinally oriented jejunal segments (mucosa intact) was examined in standard tissue baths in response to antigen (Ag) or other agents. Although control and sensitized tissues similarly contracted to stretch, bethanechol, histamine, or 5-hydroxytryptamine (5-HT), Ag contracted only sensitized segments. Contractile response 1) was specific to the sensitizing Ag, as bovine serum albumin did not induce contraction, and 2) could be passively transferred with serum containing specific IgE antibody. Mast cell degranulation after Ag challenge was suggested by a significant loss of granulated mast cells in sensitized compared with control rats challenged with Ag. Concanavalin A, which degranulates mucosal and connective tissue-type mast cells, and compound 48/80, which degranulates only connective tissue-type mast cells, produced a contractile response. Ag-induced contraction was significantly inhibited by the mucosal and connective tissue-type mast cell stabilizer doxantrazole (P less than 0.001) and the connective tissue mast cell stabilizer disodium cromoglycate (P less than 0.05). Diphenhydramine and cimetidine together blocked histamine-induced contraction but failed to affect Ag-induced contraction in sensitized tissues.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Mediation of food protein-induced jejunal smooth muscle contraction in sensitized rats. 237 65

Isolated purified rat mast cells release histamine when exposed to acetylcholine according to different patterns of sensitivity. The degree of histamine release is correlated with the levels of reaginic antibodies presumably bound to the mast cell membrane. In fact, mast cells passively sensitized with mouse myeloma IgE against egg albumin or DNP2-lysine, react to acetylcholine with a release of histamine, which is proportional to the IgE concentration in the incubation medium. The histamine release induced by acetylcholine is due to the stimulation of a muscarinic receptor. Accordingly, acetylthiocholine is unable to evoke histamine release and preincubation of sensitized cells with atropine fully inhibits the cholinergic histamine release. The histamine release evoked by acetylcholine is potentiated by the exposure of sensitized cells to the specific antigen. The present results suggest that sensitization of mast cells is a crucial factor in modulating their sensitivity to acetylcholine.
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PMID:Immunological modulation of cholinergic histamine release in isolated rat mast cells. 240 65

The production of lysophosphatidylserine has been studied in a population of rat peritoneal cells; 67% polymorphonuclear and 33% mononuclear leukocytes. Pulse-chase experiments with L-[U-14C]serine reveal a net lysophosphatidylserine production of 0.33 nmol/mg protein in 2 h of incubation. The source of lysophosphatidylserine is probably the phosphatidylserine of cells damaged during the incubation, since plasma membrane fragments obtained from the leukocytes yield higher lysophosphatidylserine production (1.9 nmol/mg protein in 1 h of incubation). Both leukocytes and plasma membranes show phosphatidylserine splitting activity when tested with vesicles of this phospholipid. In the presence of albumin a fraction of produced lysophosphatidylserine is recovered in the incubation medium. Under these conditions efficient incorporation of lysoderivative into surrounding leukocytes and conversion to phosphatidylserine requires cell activation by tetradecanoylphorbol acetate. In agreement with radiochemical data it is found that a suspension of leukocytes elicits histamine release when rat peritoneal mast cells and nerve growth factor are subsequently added. This typical, lysophosphatidylserine-dependent mast cell response is retained when leukocyte plasma membranes substitute the whole cells. These results suggest that leukocyte lysis at sites of tissue injury results in the production of a sufficient amount of lysophosphatidylserine to reach and activate surrounding mast cells.
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PMID:Lysophosphatidylserine-dependent interaction between rat leukocytes and mast cells. 244 60


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