Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20366 (substance P)
 21,176 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We compared histamine release induced by substance P with those obtained with classical secretagogues on human basophils, lung and skin fragments. We also tested the capacity of nedocromil sodium and theophylline to inhibit histamine release in these 3 experimental models. Substance P (10(-4) M) caused a noncytotoxic histamine release (about 10% of total) from basophils, lung and skin fragments. Substance P-induced histamine release was always smaller than that obtained with optimal doses of anti-IgE, formyl-methionine phenylalanine or compound 48/80. Nedocromil sodium did not prevent secretagogue-induced histamine release from basophils or sliced skin. In contrast, it significantly inhibited anti-IgE- or substance P-induced histamine release from human lung. Theophylline caused a dose-related inhibition on these 3 models. We conclude that substance P is a modest secretagogue for human basophils and mast cells, and that skin and lung mast cells are heterogeneous with respect to their response to nedocromil sodium.
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PMID:Substance P-induced histamine release from human basophils, skin and lung fragments: effect of nedocromil sodium and theophylline. 170

We compared the cutaneous reaction to intradermal injection of substance P, gastrin and histamine in asymptomatic atopic subjects with a history of hay fever and/or asthma versus non-atopic healthy volunteers. We also studied in these two groups the basophilic histamine release induced by substance P and gastrin with that obtained with anti-human IgE and Con A. Intradermal injection of substance P (3-300 pM) and gastrin (3-30 pM) caused a wheal and flare reaction which was comparable in both groups of subjects. Substance P 10(-4)M caused a mean basophilic histamine release of about 15% in atopic and non-atopic subjects. Gastrin was not effective in this model. Anti-IgE and Con A-induced histamine release was significantly higher in atopic than in non-atopic volunteers.
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PMID:Cutaneous and basophilic sensitivity to substance P and gastrin in non-atopic versus atopic subjects. 170 11

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.
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PMID:Extracellular localization of human connective tissue mast cell granule contents. 171 Jun 37

This study was undertaken to investigate the effect of estrogens on the histamine release mediated by IgE in rat peritoneal mast cells (PMC) and in sensitized human basophils. The estrogens were found to enhance the histamine release of either rat PMC and sensitized human basophils upon stimulation with anti-IgE. The enhancement was estrogens dose-dependent reaching the maximum value of 23% for rat PMC and 41% for sensitized human basophils stimulated with anti-IgE upon preincubation with 10(-8) M estrogens. Moreover, when purified PMC were used, the enhancing effect was still detected, suggesting a direct interaction between estrogens and mast cells. The enhancing effect took place quite rapidly reaching plateau levels in about 60 min. Basophils preincubated at 4 instead of 37 degrees C did not give any appreciable enhancement, suggesting that it was temperature-dependent and that the effect observed was not due to cytotoxicity. Incubation of PMC or human basophils with estrogens alone, without challenge with anti-IgE, did not give any detectable histamine release. The enhancement of histamine release by estrogens is probably mediated by IgE molecules present on the cell membrane, since this effect was not observed on challenge with substance P or compound 48/80, two segretagogues known to induce histamine release not via IgE.
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PMID:Modulation of rat peritoneal mast cell and human basophil histamine release by estrogens. 171 2

The association between mast cells (visualized by routine staining and immunohistochemistry for histamine) and capsaicin-sensitive nerves (containing calcitonin gene-related peptide (CGRP) and substance P (SP] was studied in the pig. In the 1-ethyl-3(3-diethylaminopropyl)carbodiimide (EDCDI)-fixed skin tissue, histamine-containing mast cells and CGRP/SP-positive nerves were found in close association around blood vessels. In the EDCDI-fixed airway mucosa, only single histamine-containing mast cells were detected. However, many alcian blue-positive mast cells were found, sometimes close to the airway epithelium where CGRP SP-containing nerve were abundant. The CGRP/SP-containing nerve fibres were absent 2 days after systemic capsaicin pretreatment, but no changes in the number and distribution of tissue mast cells, granulocytes or lymphocytes, or the number of blood leukocytes were detected. Local injection of allergen, histamine and capsaicin into the skin of pigs actively sensitized with ascaris antigen caused a rapid light red-flare (vasodilation) reaction. Allergen and histamine, but not capsaicin, also produced plasma protein extravasation. In contrast to the absent flare, the protein extravasation response still occurred in capsaicin-treated pigs. The sensitivity to ascaris antigen was mediated by an IgE-like antibody. We conclude that a functional and morphological relationship exists between histamine-containing mast cells and capsaicin-sensitive sensory nerves in the pig skin. Mast cells and sensory nerves are also found in the airway mucosa and appear to be closely associated with the epithelium.
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PMID:Association between histamine-containing mast cells and sensory nerves in the skin and airways of control and capsaicin-treated pigs. 171 54

As part of an ongoing investigation of human mast cell heterogeneity, we have isolated, partially purified, and characterized the uterine mast cell and compared it with mast cells isolated from other organs. The average histamine content of myometrium and leiomyofibroma obtained from hysterectomies was 2.1 +/- 0.3 (mean +/- SEM) microgram/g of tissue (n = 10), and the histamine content of the two tissues did not differ significantly. A mild collagenase, hyaluronidase, and DNase digestion was used to disperse the uterine mast cells, with an average yield of 9.5% (range, 0 to 21%). The average histamine/uterine mast cell was 2.1 +/- 0.2 pg (n = 3), and 61 +/- 7% (n= 3) of the uterine mast cells survived overnight culture. Early purification efforts with Percoll gradients have yielded up to 80% pure uterine mast cells, with an average of 27 +/- 10% (n = 5). Uterine mast cells released histamine in response to the secretogogues anti-IgE and A23187 but did not respond to substance P or to the basophil secretogogues FMLP, C5a, and 12-O-tetradecanoylphorbol-13-acetate. After 1 microgram/ml anti-IgE stimulation, the uterine mast cell appeared to make significant quantities of PGD2 (89 +/- 26 ng/10(6) cells, n = 6) (p less than 0.05), as assayed by RIA. Simultaneously, leukotriene C4 release was 45 +/- 15 ng/10(6) cells, (n = 6) (p less than 0.05), as assayed by RIA. Combined gas-chromatography mass spectroscopy analysis of anti-IgE-stimulated cell supernatants confirmed the production of PGD2. In pharmacologic studies, isobutyl-methylxanthine and isoproterenol blocked anti-IgE-induced histamine release. The uterine mast cell is similar to the lung mast cell in terms of response to secretogogues and release of arachidonic acid metabolites. Ultrastructurally, the uterine mast cell contains scroll granules, crystal granules, combined granules, homogeneously dense granules, and large lipid bodies, many with focal lucencies within them. Particle granules, most frequently present in gut mast cells of mucosal origin, were absent from uterine mast cells. Although certain features are analogous to the ultrastructure of skin or lung mast cells, the combination of structures is distinctive for uterine mast cells.
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PMID:Human uterine mast cells. Isolation, purification, characterization, ultrastructure, and pharmacology. 171 65

Unlike human mast cells associated with mucosal surfaces such as lung, adenoids, tonsils and intestine, skin mast cells may be stimulated to release histamine by the neuropeptides substance P, vaso-active intestinal polypeptide and somatostatin or by other basic secretagogues such as morphine and compound 48/80. Release of histamine by neuropeptides is rapid and accompanied by minimal generation of the eicosanoids prostaglandin D2 and leukotriene C4. Transient elevations of intracellular calcium are associated with mediator secretion induced by both immunological and non-immunological stimulation, that induced by anti-IgE being derived from extracellular sources through channels in the plasma membrane while that stimulated by neuropeptides is mobilized intracellularly. Similarly, elevations of intracellular cyclic AMP induced by anti-IgE occur only in the presence of extracellular calcium, whereas with substance P elevations are apparent even in the absence of extracellular calcium. With the latter stimulus, histamine release is complete before the peak cyclic AMP is achieved. Despite these biochemical and temporal differences, degranulation induced by both secretagogues proceeds by compound exocytosis which is indistinguishable under the electron microscope. From these results we suggest that IgE-dependent and neuropeptide stimulation of human skin mast cells proceed by distinct biochemical pathways which eventually merge to produce exocytosis of their preformed granule-associated mediators.
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PMID:Neuropeptide-induced secretion from human skin mast cells. 171 93

Mast cells are involved in allergic reactions where they release numerous vasoactive and other mediators in response to IgE and antigen. They are also activated by neuropeptides and are found in close contact with neurons. Mast cell heterogeneity has now been documented for mucosal mast cells and connective tissue mast cells. Rat brain mast cells were studied in a perfusion system and were shown to release serotonin in response to the mast cell secretagogue compound 48/80 (C48/80). High-potassium neuronal depolarization also released serotonin, but this was calcium dependent, not associated with beta-hexosaminidase, and was unaffected by prior treatment with C48/80. Neuronal depolarization, however, was associated with somatostatin secretion and substantially reduced subsequent C48/80 stimulation, an effect abolished by neonatal treatment of the animals with capsaicin. Perfusion with somatostatin and substance P also induced brain mast cell serotonin release. C48/80 stimulation of combined thalamic and hypothalamic slices after neuronal depolarization substantially reduced the C48/80 effect, suggesting the possible presence of endogenous inhibitors released from the hypothalamus. Finally, the alpha 2-receptor agonist clonidine had a slight stimulatory effect. These results indicate that brain mast cell serotonin release may be regulated by endogenous neurotransmitters and/or neuromodulators.
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PMID:Endogenous regulation of rat brain mast cell serotonin release. 172 Apr 23

Mast cells of the human skin not only release mediators following immunological activation, but may also be stimulated to release histamine by the neuropeptides substance P, vasoactive intestinal polypeptide and somatostatin or by other basic secretagogues such as morphine, poly-L-lysine and compound 48/80. Release of histamine under these conditions is rapid and accompanied by minimal generation of the eicosanoids, prostaglandin (PG)D2 and leukotriene (LT)C4. Transient elevations of intracellular calcium are associated with mediator secretion induced by both stimuli, that induced by anti-IgE being derived from extracellular sources through channels in the plasma membrane while that stimulated by neuropeptides is mobilized intracellularly. Similarly, elevations of intracellular cyclic adenosine monophosphate (AMP) induced by anti-IgE occur only in the presence of extracellular calcium whereas with substance P elevations are apparent even in the absence of extracellular calcium. With the latter stimulus, histamine release is complete before the peak cyclic AMP is achieved. Histamine release stimulated by both secretagogues is unaffected by sodium cromoglycate or nedocromil sodium but is reduced by both salbutamol and isobutylmethylxanthine. Despite these biochemical and temporal differences, degranulation induced by both secretagogues proceeds by compound exocytosis which is indistinguishable under the electron microscope.
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PMID:Mediator secretion from human skin mast cells provoked by immunological and non-immunological stimulation. 172 14

The effect of tranilast, an inhibitor for IgE-mediated mediator release from mast cells, on plasma extravasation induced by the intradermal injection of substance P in rats was examined. Tranilast (100 mg/kg, intraperitoneally) decreased plasma extravasation induced by substance P (10(-7)-10(-5) M). Tranilast decreased plasma extravasation induced by the amino-terminal peptide substance P1-9 (10(-6)-10(-4) M), which is active for rat mast cells, but not by the carboxy-terminal peptide substance P6-11 (10(-6)-10(-4) M), which is inactive for the mast cells. Therefore, tranilast prevents substance P-induced plasma extravasation most likely by inhibiting mast cell degranulation.
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PMID:Inhibitory effect of tranilast on substance P-induced plasma extravasation in rat skin. 172 11


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