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)

Antigen (egg albumin) injections, which stimulate mucosal mast cells to secrete mediators, were paired with an audiovisual cue. After reexposure to the audiovisual cue, a mediator (rat mast cell protease II) was measured with a sensitive and specific assay. Animals reexposed to only the audiovisual cue released a quantity of protease not significantly different from animals reexposed to both the cue and the antigen; these groups released significantly more protease than animals that had received the cue and antigen in a noncontingent manner. The results support a role for the central nervous system as a functional effector of mast cell function in the allergic state.
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PMID:Pavlovian conditioning of rat mucosal mast cells to secrete rat mast cell protease II. 291 21

Cutaneous late-phase allergic reactions (LPR) are characterized by an early, immediate hypersensitivity whealing reaction followed by persistent, localized induration that peaks 6 to 8 hours later. In this study we used rodents to examine the relationship between vascular permeability (VP) and induration during LPR. Efflux of macromolecular tracers from the vasculature into skin was measured with the use of radiolabeled albumin and neutral dextran tracers having large molecular radii. To induce LPR immunologically, we used either intradermal injections of antirat IgE or passive cutaneous sensitization with IgE antidinitrophenyl followed 24 hours later by intravenous injection of albumin-dinitrophenyl. [125I]albumin and [3H]dextran tracers were injected intravenously before and at various intervals after the induction of LPR. Although a marked increase in VP occurred within the first 30 minutes after induction of mast cell degranulation, analysis of radiolabeled tracer accumulation at 2, 4, 8, and 24 hours failed to demonstrate any further increase in VP. These findings indicate that the induration observed in rodent LPR is not associated with increased VP beyond the immediate hypersensitivity stage and suggest that impairment of lymphatic drainage, cellular infiltration, and/or fibrin deposition are contributing factors.
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PMID:Dissociation of cutaneous vascular permeability and the development of cutaneous late-phase allergic reactions. 292 85

The recent development of a technique for quantitative measurement of conjunctival microvascular permeability has permitted detailed pharmacological evaluation of H1- and H2-receptor involvement in histamine-induced increases in conjunctival microvascular permeability and the role of histamine in microvascular permeability changes associated with immediate hypersensitivity responses in the conjunctiva. The conjunctival microvascular permeability response to histamine appears to be entirely mediated by H1-receptors. Pyrilamine (H1-receptor antagonist) virtually abolished the increase in conjunctival extravascular albumin content produced by graded doses of histamine, whereas cimetidine (H2-receptor antagonist) was ineffective. Moreover, selective histamine H2-receptor agonists did not elicit a dose-dependent vasopermeability response in the conjunctiva. Although H1-receptor blockade essentially abolished the microvascular permeability response to histamine, it only partially attenuated the conjunctival microvascular permeability response associated with immediate hypersensitivity and compound 48-80. It appears that conjunctival inflammation caused by mast cell degranulation comprises both a histaminergic and a nonhistaminergic component.
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PMID:Conjunctival immediate hypersensitivity: re-evaluation of histamine involvement in the vasopermeability response. 293 47

In previous studies we showed that rats sensitized to egg albumin respond to in vivo intraluminal antigen with decreased net absorption of Na+, Cl-, and water. These abnormalities are associated with high serum levels of immunoglobulin E (IgE) antibodies and mucosal mast cell degranulation. In the present in vitro study electrical parameters, unidirectional fluxes of Na+ and Cl-, and levels of cAMP were determined in jejunum from sensitized and control rats during a basal period and after antigen addition. In Ussing chambers potential difference and short-circuit current increased significantly in tissue from sensitized rats after addition of 100 micrograms/ml of egg albumin to both mucosal and serosal surfaces. These changes were accompanied by a reversal of net Cl- absorption to net Cl- secretion. The presence of doxantrazole, a mast cell-stabilizing agent, in the buffer prevented these abnormalities. No changes occurred in response to antigen challenge in tissue from controls. In a further series of experiments the antigen was added only to the mucosal side of the tissue in Ussing chambers. In these studies short-circuit current increased after a lag period of approximately 25 min and was significantly increased (P less than 0.025) at 35 min. cAMP levels increased significantly in jejunal slices from sensitized rats exposed to antigen for 2 min. Our findings suggest that the in vivo transport abnormalities induced by IgE-mediated mucosal reactions to a food protein are related to antigen stimulation of a Cl- secretory process.
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PMID:Intestinal anaphylaxis in the rat: jejunal response to in vitro antigen exposure. 300 74

Inflammatory reactions induced by TPA (12-O-tetradecanoylphorbol 13-acetate)-type tumor promoters, including TPA, teleocidin and aplysiatoxin, and chemical mediators responsible for such inflammatory reactions were analyzed. The tumor promoter dissolved in a 0.8% sodium carboxymethyl cellulose solution was injected into a subcutaneous air pouch preformed on the dorsum of rats. Within 30 min after the injection, vascular permeability as measured by the leakage of labeled albumin into the pouch fluid was increased, with a concomitant increase in histamine level. This increase in vascular permeability was inhibited by a histamine antagonist, pyrilamine, and a serotonin antagonist, methysergide. Vascular permeability at 4 h was not inhibited by pyrilamine or methysergide but was inhibited by a cyclooxygenase inhibitor, indomethacin, with a parallel decrease in the prostaglandin E2 level in the pouch fluid. These results suggest that the TPA-type tumor promoters induce inflammation by the mechanism of mast cell degranulation within a short period, this being followed by the stimulation of arachidonic acid metabolism. The mechanism of the in vivo effect of the TPA-type tumor promoters is discussed and compared with in vitro effects that we have previously reported.
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PMID:Analysis of tumor-promoter-induced inflammation in rats: participation of histamine and prostaglandin E2. 311 92

The accumulation of malignant ascites is a significant cause of morbidity and mortality in patients with intraabdominal malignancies. However, the cause of malignant ascites is unknown. In this study, we used the rat cremaster muscle preparation to determine if and how malignant ascites could produce protein leakage from normal blood vessels which would lead to fluid accumulation in the peritoneal cavity. The rat cremaster muscle, with nerves and blood vessels to the animal intact, was prepared for microscopic observations of the microcirculation. Serum albumin was tagged to fluorescein isothiocyanate and injected into the rat. Fluorescent microscopy was used to quantitate leakage of the tagged albumin into the interstitial tissue. Malignant ascites was collected from a patient with metastatic breast cancer. The ascites fluid was placed on the cremaster muscle and it induced protein leakage from the normal blood vessels of this tissue. Protein leakage was partially blocked by diphenhydramine (10(-4) M) and by mast cell depletion with compound 48/80. There was a high level of C3a in the malignant ascites solution but C3a did not increase during the exposure period. These data suggest that activated complement in malignant ascites may release histamine from mast cells to cause protein leakage of the normal vasculature. The movement of protein into the peritoneal cavity would be followed by water, thus increasing the volume of the ascites and exacerbating the clinical condition.
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PMID:Human malignant ascites and histamine-induced protein leakage from the normal microcirculation. 325 8

Kinins are generated in nasal secretions during allergic reactions and during induced rhinovirus colds. To determine if kinins may contribute to the symptomatology of these inflammatory reactions, 8 subjects were challenged with increasing doses of bradykinin or with placebo. Levels of albumin, histamine, and N-alpha-tosyl-L-arginine methyl ester (TAME)-esterase were measured in nasal lavages, and symptom scores were noted. No symptoms or increases in mediators or protein were observed after placebo challenge. Symptom scores increased in a dose-dependent manner, however, in response to bradykinin challenge. Increased symptoms were associated with significant increases in albumin and TAME-esterase activity, but no increases in histamine were observed. Nasal conductance measurements confirmed that bradykinin induces dose-dependent unilateral obstruction in the challenged nostril. Other common symptoms were rhinorrhea and, of particular relevance to rhinovirus infections, a persistent sore throat. We conclude that bradykinin causes increased vascular permeability and rhinitis, which are independent of mast cell mediator release. Kinins may, therefore, contribute to the symptomatology of inflammatory reactions of the upper airways, including the common cold.
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PMID:Nasal provocation with bradykinin induces symptoms of rhinitis and a sore throat. 334 41

Ponies with recurrent airway obstruction (principal ponies) and their controls were given aerosolized Micropolyspora faeni antigen via endotracheal tube during a period when the principal ponies were in disease remission. In both groups of ponies, we performed bronchoalveolar lavage (BAL) and measured pulmonary function at base line, and 5 hours after aerosol administration of 30 ml of 0.9% NaCl solution or 30 ml of 1% w/v particulate M faeni antigen in 0.9% NaCl solution. In both groups of ponies, aerosolized M faeni antigen increased WBC count, neutrophil numbers, and albumin concentration in BAL fluid, but macrophage numbers decreased. In the principal ponies, BAL mast cell numbers were decreased 5 hours after administration of M faeni antigen. The M faeni antigen had no effect on the mechanical properties of the lungs or on gas exchange in the control ponies, but did increase respiratory frequency minute ventilation and pulmonary resistance, and decreased arterial oxygen tension in the principal ponies. Changes in pulmonary function were apparent only in the principal ponies, which suggests that neutrophils, per se, do not cause pulmonary dysfunction and that M faeni may be one of the etiologic agents involved in chronic obstructive pulmonary disease.
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PMID:Aerosolized Micropolyspora faeni antigen as a cause of pulmonary dysfunction in ponies with recurrent airway obstruction (heaves). 340 Sep 31

The response of the rat proximal colon to an immunoglobulin E (IgE)-mediated hypersensitivity reaction was examined. Rats were sensitized to egg albumin (EA) by intraperitoneal injection, and serum titers of specific anti-EA IgE were measured at 14 days. Sensitized animals had titers of greater than or equal to 1:64, whereas no anti-EA IgE antibodies were detected in controls. Water and electrolyte absorption in the proximal colon, before and during antigen challenge, was measured by in vivo marker perfusion. Antigen challenge resulted in significant inhibition of water, Na+, Cl-, and K+ absorption in vivo. Proximal colonic tissue from sensitized and control animals was studied in Ussing chambers under short-circuited conditions. Antigen challenge of sensitized tissue resulted in significant increases in short-circuit current due to the induction of active Cl- secretion. No such changes were seen in control tissue. The abnormalities induced by antigen challenge in tissue from sensitized animals was blocked by doxantrazole (10(-3) M), a mast cell stabilizer. The findings indicate that IgE-mediated reactions in rat proximal colon to a food protein cause pertubations in water and electrolyte transport secondary to active Cl- secretion and these abnormalities appear to be due to mast cell degranulation.
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PMID:Intestinal anaphylaxis: in vivo and in vitro studies of the rat proximal colon. 340 78

Acute cutaneous photosensitivity is a major manifestation of certain forms of human porphyria and also occurs in patients treated with hematoporphyrin derivative (HpD) photoradiation for the diagnosis and treatment of malignant tumors. In this study a quantitative animal model useful for in vivo studies of acute porphyrin photosensitization in cutaneous tissue was developed. C3H mice injected with HpD and irradiated 6 h later with 405 nm energy developed a 40-90% increase in ear thickness which was present immediately after irradiation and persisted for at least 24 h. No ear swelling occurred in animals receiving 405 nm radiation alone or HpD alone. Histologically, this photosensitivity reaction was manifest as edema, vascular dilatation, and mast cell degranulation immediately after irradiation followed by an influx of polymorphonuclear leukocytes and epidermal necrosis 24 h later. Tissue injury evoked by HpD and light was accompanied by extravasation of intravenously administered 125I-labeled albumin in the irradiated ears, indicating that photosensitization was accompanied by transudation of serum into the site of tissue injury. An in vivo correlation of this approach was verified by detection of measurable increase in ear thickness in irradiated mice rendered porphyric by the ingestion of a griseofulvin-containing diet. The mouse ear swelling model offers a useful system with which to study acute porphyrin photosensitization in the skin, and may lead to important new insights into the pathogenesis and prevention of this form of phototoxicity.
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PMID:Cutaneous porphyrin photosensitization: murine ear swelling as a marker of the acute response. 371 77


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