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)

This study investigated the effect of radiation on clinical and histologic changes, and on cutaneous eicosanoid metabolism, in Skh:HR-1 hairless albino mice rendered protoporphyric by the administration of collidine. At 0.1-18 h after exposure to 12 kJ/m2 of 396-406 nm irradiation, thicknesses of back skin and ears were measured, and histologic changes were evaluated by using hematoxylin and eosin (H-E) and Giemsa's stains. Activities of eicosanoid-metabolizing enzymes in epidermal and dermal homogenates were assessed by incubating the tissue homogenates with 3H-AA, followed by quantitation of the eicosanoids generated by radio-TLC. In irradiated protoporphyric mice, an increase of back-skin thickness was noted at 0.1 h, reaching a peak at 18 h, whereas maximal increase in ear thickness was observed at 12 h. Histologic changes included dermal edema, increased mast cell degranulation, and mononuclear cells in the dermis. In these irradiated protoporphyric animals, generations of 6 keto-PGF1a, PGF2a, PGE2, PGD2, and HETE by epidermal eicosanoid-metabolizing enzymes were markedly suppressed at all the timepoints studied. Dermal eicosanoid-metabolizing enzymes of irradiated protoporphyric mice generated increased amounts of PGE2 and HETE at 18 h, probably reflecting the presence of dermal cellular infiltrates. The suppression of the activities of epidermal eicosanoid-metabolizing enzymes was prevented by intraperitoneal injection of WR-2721, a sulfhydryl group generator, prior to irradiation, suggesting that the suppression was secondary to photo-oxidative damage of the enzymes during the in vivo phototoxic response. These results suggest that the effect of protoporphyrin and radiation on cutaneous eicosanoid metabolism in this animal model in vivo is that of a down regulation of the activities of epidermal eicosanoid-metabolizing enzymes.
J Invest Dermatol 1991 Sep
PMID:Irradiation of protoporphyric mice induces down-regulation of epidermal eicosanoid metabolism. 165 71

Treatment of chronic urticaria presents a challenge to both practitioner and patient. Traditional H1 antagonists with good efficacy but substantial side effects are being supplanted in many cases by nonsedating H1 antagonists such as terfenadine and astemizole. Antidepressant medications and combinations of H1 and H2 antagonists offer improved results for selected patients. Further development and investigation of mast cell stabilizers and inhibitors of urticaria mediators other than histamine hold promise. A better understanding of the underlying pathogenesis remains the greatest hope of formulating rational and effective therapy.
J Am Acad Dermatol 1991 Jul
PMID:Pharmacologic therapy for urticaria. 167 97

Leukocyte trafficking in normal and diseased skin appears to be initially governed by endothelial surface glycoproteins that promote adhesive interactions with circulating leukocytes. In a separate study, we have demonstrated that one of these glycoproteins, endothelial-leukocyte adhesion molecule-1 (ELAM-1), is rapidly induced on postcapillary dermal venules as a direct consequence of experimentally-elicited degranulation of adjacent mast cells (Proc Natl Acad Sci USA 86:8972-8976, 1989). A principle endogenous mediator of mast cell degranulation is the neuropeptide substance P. In this study, we exposed organ cultures of neonatal human foreskins for 45 min to substance P or to a substance P analogue (D-pro4, D-trp7,9)SP(4-11) that binds to the identical mast cell surface receptor but which does not provoke histamine release. Dermal mast cells were uniformly degranulated only in explants exposed to substance P, as judged by ultrastructural analysis. After subsequent culture in medium alone for 6 h, superficial venules of explants exposed to substance P showed evidence of ELAM-1 induction, as documented histochemically using H4/18 monoclonal antibody. ELAM-1 was not induced by substance P analogue. Furthermore, preincubation of explants with analogue or with the mast cell inhibitor, cromolyn sodium, abrogated the ability of substance P to induce ELAM-1. From these results we suggest that substance P endogenously released by dermal nerve fibers upon physiologic or electrical stimulation may be important in the regulation of endothelial-leukocyte interactions in vivo. This concept provides further evidence for a neurogenic and psychogenic modulation of the immune response, and may be relevant to the course of naturally occurring dermatoses (e.g., psoriasis) that are commonly exacerbated by emotional stress.
J Invest Dermatol 1990 Apr
PMID:Substance P induces the expression of an endothelial-leukocyte adhesion molecule by microvascular endothelium. 169 Feb 49

The flare and weal reactions to intradermal injections of histamine and the peptide substance P were measured in a group of patients with atopic dermatitis and compared to reactions in a non-atopic control group. There was no significant difference in the flare areas between the controls and atopics with either reagent. The weal volumes after injection of substance P and histamine were significantly larger in the atopic group. As substance P causes mast cell histamine release, the increased weal volumes produced by substance P in the atopics may be entirely due to the exaggerated atopic weal reaction to histamine.
Br J Dermatol 1990 Mar
PMID:Cutaneous reactions to substance P and histamine in atopic dermatitis. 169 Oct 13

The onset of mastocytosis occurs between birth and 2 years of age in approximately 55% of all cases; an additional 10% develop the disease before the age of 15 years. Mastocytosis in these age groups differs in many respects from mastocytosis that has its onset in adulthood. The typical presentation of pediatric-onset mastocytosis consists of cutaneous manifestations: either a solitary mastocytoma, urticaria pigmentosa, or, less commonly, diffuse cutaneous mastocytosis. Particularly in infants, bullous eruptions may occur. Mastocytosis in infants and children may involve internal organs, including the bone marrow and the gastrointestinal tract, although such manifestations appear to be less common in children than in adults. Plasma histamine levels may be elevated in pediatric-onset mastocytosis. Treatment usually involves the use of H1 and H2 antihistamines to control itching and to control the hypersecretion of gastric acid that may occur. The prognosis for children with mast cell disease is variable; approximately half of the children with urticaria pigmentosa may experience resolution of lesions and symptoms by adolescence.
J Invest Dermatol 1991 Mar
PMID:Pediatric mastocytosis. 170 49

In early phases of cutaneous inflammation, connective tissue mast cell degranulation is associated with apparent secretion and externalization of immunoreactive chymotryptic serine proteinase. To determine whether this event is associated with structural evidence of granule externalization, we studied the sequential evolution of IgE-mediated hypersensitivity in vivo, as well as mast cell degranulation provoked by a variety of stimuli in cultured explants of human skin. By 1 min after intradermal antigen challenge with ragweed extract, mast cell degranulation was associated with apparent extrusion of intragranule constituents into the pericellular connective tissue. Similar features typified cultured skin explants exposed for 45 min to anti-IgE and other mast cell secretagogues (morphine sulfate, calcium ionophore A23187, compound 48/80, and substance P). Once externalized, granule constituents could be identified within the dermal matrix by their rounded contour and structural similarity to solubilized granule matrices remaining within actively secreting cells. These data indicate that externalization of connective tissue mast cell granule contents occurs early after secretagogue exposure, potentially accounting for infrequent documentation of this event in naturally occurring dermatoses. The ability to recognize externalized granule products at a morphologic level should facilitate the understanding of interactions between mast cell-derived mediators and target structures of the dermal microvasculature.
J Invest Dermatol 1991 Jun
PMID:Extracellular localization of human connective tissue mast cell granule contents. 171 Jun 37

To evaluate further the interactions of C5a and mast cells in cutaneous inflammation, the ability of human native C5a (nC5a) (10 to 500 ng/ml) and human recombinant C5a (rC5a) (10 ng/ml to 100 ng/ml) to induce histamine release from purified BALB/c cutaneous mast cells (CMC) and peritoneal mast cells (PMC) was analyzed. It was found that nC5a induced histamine release from CMC but not from PMC, with a maximal net release at 250 ng/ml nC5a (22.8 +/- 2.6%). Kinetic experiments demonstrated that nC5a-induced maximal net histamine release occurred 5 min after the presentation of this stimulus (25.8 +/- 6.0%). Using rC5a and CMC, dose-response studies indicated a maximal net release of 7.0 +/- 1.7% at rC5a of 10 ng/ml, and kinetic studies showed a maximal net release at 5 min of incubation (12.9 +/- 1.6%). Release induced by rC5a was calcium-dependent, and peaked at 30 degrees C. These results indicate that functional heterogeneity exists between the CMC and the PMC of BALB/c mice, that C5a is a relevant stimulus for characterization of this heterogeneity, and that CMC from these animals can serve as a convenient in vitro model for the study of human C5a-mast cell interactions. In vivo, injections of nC5a (25-100 ng) and rC5a (25-100 ng) into the skin of BALB/c mice induced an increase in cutaneous vasopermeability, as assessed by the extravasation of intravenously injected 125I-bovine serum albumin. nC5a induced a dose-dependent increase in vasopermeability, whereas alterations induced by rC5a plateaued at 50 ng. The C5a-induced vasopermeability was markedly enhanced in animals that had been previously treated with an inhibitor of serum carboxypeptidase, which converts C5a to the less potent derivative, C5a des Arg. These findings suggest that carboxypeptidase plays an important role in vivo in the modulation of C5a-induced cutaneous inflammation in murine skin.
J Invest Dermatol 1991 Aug
PMID:C5a, cutaneous mast cells, and inflammation: in vitro and in vivo studies in a murine model. 171 20

The aim of the present study was to test further our previous hypothesis that the inflammatory reaction in psoriasis is neurogenic. For this purpose, contact sites between mast cells and sensory nerves were morphometrically analysed in the basement membrane zone, papillary dermis and three dermal zones of lesional/non-lesional psoriatic and lichen planus skin as well as in healthy control skin. The analyses were made on sections stained with a histochemical double stain developed for this study. With the double stain, active mast cell tryptase was stained blue enzyme histochemically, and the sensory nerves black using specific monoclonal anti-neurofilament antibodies with immunogold. In psoriatic lesions, both mast cells and mast cell--nerve contacts were markedly more frequent in the basement membrane zone and in the papillary dermis when compared with the corresponding areas in the other groups. Mast cell numbers were increased in both lesional and symptom-free skin in lichen planus, but no increase was found in the mast cell--nerve contacts. Increased contacts between mast cells and sensory nerves indicate that the elements exist for neurogenic inflammation in psoriatic lesions. These increased contacts are not due to the extensive inflammatory reaction only, because they were not observed in lichen planus lesions.
Arch Dermatol Res 1991
PMID:Quantitative analysis of contact sites between mast cells and sensory nerves in cutaneous psoriasis and lichen planus based on a histochemical double staining technique. 172 96

A lesion of lichen nitidus in a 53-year-old man was examined by histology and electron microscopy. The histology showed typical features. The electron microscopy revealed primary changes in hydropic degeneration of basal cells which possibly indicated severe edema between the basal keratinocytes and in the subepidermal area. The basal keratinocytes themselves were not particularly altered, except for clustered micro-vacuolar structures in a small portion of the peripheral cytoplasm. In one of the eight blocks observed, the cytoplasmic process of a mast cell was found between the basal keratinocytes, indicating that mast cells may possibly infiltrate the epidermis in lichen nitidus. Scattered mast cells in the dermis were also noted. Thus primary pathologic changes of lichen nitidus may be induced by severe edema, which was accompanied by inflammatory cells including mast cells, in the region of the dermal-epidermal junction.
J Dermatol 1991 Aug
PMID:Lichen nitidus: a histologic and electron microscopic study. 176 95

Three patients with chronic urticaria, two of whom also had angioedema, were treated with oral cyclosporine, 6 mg/kg per day. In each patient, complete resolution of symptoms occurred within the first week of therapy; however, all patients eventually had to stop therapy as a result of side effects. On stopping therapy, all side effects resolved and the urticaria and angioedema recurred. Although cyclosporine therapy is not an appropriate treatment of urticaria, the results of this preliminary study suggest that cyclosporine and related drugs should be investigated in the treatment of mast cell-mediated diseases.
J Am Acad Dermatol 1991 Dec
PMID:Oral cyclosporine for severe chronic idiopathic urticaria and angioedema. 143 Mar 81


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