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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Incubation of bovine serum albumin (BSA), rat serum albumin or rat plasma with medium conditioned by endotoxin stimulated rat peritoneal macrophages produced an activity that released histamine from isolated rat serosal mast cells. The amount of histamine-releasing activity (HRA) produced increased with the length of the incubation period, with the concentration of albumin, with the number of macrophages stimulated, and with the duration of exposure of the macrophages to endotoxin. Moreover, the formation of the HRA showed a dependency on the pH of the incubation medium with an optimum at pH 4.5. Boiling the medium conditioned by stimulated macrophages before its incubation with albumin or including the acid protease inhibitor, pepstatin with the conditioned medium prevented the formation of HRA. The generation of HRA was not inhibited by pretreatment of the macrophages with the inhibitor of protein synthesis, cycloheximide. Media from macrophages not stimulated with endotoxin failed to generate HRA. Histamine release from mast cells in response to the HRA was inhibited by pretreatment of the cells with antimycin A and deoxyglucose or by preincubation in Ca-free Locke's solution containing a calcium chelating agent. When injected intradermally into anesthetized Evan's Blue treated rats, the generated HRA produced a change in vascular permeability that was prevented by the H1 antagonist, diphenhydramine. Treatment of the HRA with carboxypeptidase A reduced its ability to stimulate histamine release from mast cells. Histamine-Releasing Peptide (HRP), a neurotensin-related octapeptide, shown previously by us to be formed by the action of cathepsin D or pepsin on albumin, was identified by radioimmunoassay in acid:acetone extracts of the histamine-releasing activity. It is concluded that the formation of HRA is due to the actions of enzymes released from macrophages acting on albumin. It is suggested that such histamine-releasing activity could be formed during the later stages of the inflammatory response and that HRP is one of the peptides present.
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PMID:Formation of histamine-releasing activity from albumin by medium conditioned by endotoxin-stimulated rat peritoneal macrophages. 138 Jul 64

In this study, we have attempted to determine whether mouse peritoneal mast cells released histamine in response to IL-3. Recombinant mouse (m)IL-3 induced histamine release from mouse peritoneal mast cells in a dose-dependent fashion. Histamine release did not occur in the absence of phosphatidyl serine (PS), and was dependent on PS concentrations. The release was 14.3 +/- 3.8 and 43.5 +/- 11.5% (mean +/- SEM, n = 5) at 1 nM IL-3 in the presence of 10 and 20 micrograms/ml of PS. Calcium was required for the response, and in the absence of calcium, significant histamine release was not observed. The kinetics were slower than those of anti-IgE-induced response. IL-3-induced histamine release reached a peak within 15 min, while that by anti-IgE reached 80% of the maximum in 3 min. Lower concentrations of IL-3, which failed to directly induce histamine release, did not enhance anti-IgE-induced histamine release. Other cytokines, including mIL-4, mIL-5, m-granulocyte-macrophage colony-stimulating factor, human (h)IL-1 alpha, hIL-1 beta and hIL-8, neither induced histamine release nor enhanced anti-IgE induced histamine release. IL-4 had no capacity to enhance IL-3-induced histamine release. These results suggest that locally produced IL-3 might modulate mast cell-related inflammation through histamine release from mast cells.
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PMID:Mouse IL-3 induces histamine release from mouse peritoneal mast cells. 138 45

Using enzyme-dispersed canine oxyntic mucosal cells, we studied regulation of histamine release from fractions in which mast cells were largely removed by density gradient. Histamine-like immunoreactivity was demonstrated using peroxidase-anti-peroxidase immunohistochemistry. Histamine-containing cells in the small cell elutriator fractions (SCEF) were further separated by albumin step density gradients. Approximately 2.5% of cells in the low density fraction (LDF) contained histamine-like immunoreactivity; this fraction was largely depleted of the more dense mast cells (0.5%). These two fractions were cultured for 48-64 h on a Matrigel substrate. The cell content of histamine and release into the medium were measured by radioenzymatic assay. Gastrin, carbachol, and forskolin increased histamine release from the LDF. The induction of histamine release by gastrin was evident within 5 min and was sustained for at least 60 min. The response to gastrin was dose dependent between concentrations of 10(-11) and 10(-8) M. In contrast, in the mast cell-enriched SCEF, basal release was higher and gastrin was without effect; however, concanavalin A stimulated and epinephrine inhibited histamine release indicating that histamine-release mechanisms were intact in this fraction. Our methods provide a preparation of low density oxyntic mucosal histamine cells that demonstrate gastrin-responsive histamine release; we speculate that enterochromaffin-like cells account for this gastrin response.
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PMID:Gastrin induction of histamine release from primary cultures of canine oxyntic mucosal cells. 138 57

To examine the effects of the atmospheric pollutant formaldehyde on functionally distinct mast cells, peritoneal mast cells (PMC), intestinal mucosal mast cells (IMMC) and mouse bone-marrow-derived mast cells (BMMC) were incubated with various concentrations of formaldehyde. Pretreatment for 30 min with up to 100 micrograms/ml formaldehyde was not cytotoxic to mast cells. Formaldehyde (1-10 micrograms/ml) alone induced low levels of histamine release (< 10%) from IMMC and BMMC. Antigen-induced histamine release was significantly increased in both PMC pretreated with low concentrations of formaldehyde (5-20 micrograms/ml) and BMMC pretreated with 10 micrograms/ml formaldehyde but decreased in PMC pretreated with a higher concentration (100 micrograms/ml) of formaldehyde. By contrast, antigen-induced histamine release was decreased in IMMC pretreated with formaldehyde in a dose-dependent manner. Histamine release stimulated with A23187 was also increased in PMC pretreated with a low concentration (10 micrograms/ml) of formaldehyde but decreased in those pretreated with a higher concentration (100 micrograms/ml) of formaldehyde. Pretreatment with 10 micrograms/ml formaldehyde significantly enhanced beta-hexosaminidase release from PMC stimulated with antigen or A23187. Compared to sham-treated PMC, PMC pretreated with formaldehyde expressed a markedly depressed natural cytotoxicity for the tumor target WEHI-164 (an assay of tumor necrosis factor alpha activity). These results suggest that formaldehyde modifies various mast cell functions through alterations in cellular metabolism. Such effects may be important in respiratory and other diseases associated with formaldehyde exposure.
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PMID:Mast cell response to formaldehyde. 1. Modulation of mediator release. 138 64

In the rat, gastric histamine is stored predominantly in the enterochromaffin-like (ECL) cells, which are located basally in the oxyntic mucosa. The functional significance of histamine in the ECL cells is a matter of speculation. In this study the effect of depletion of histamine on the properties and ultrastructure of the ECL cells was examined. Histamine synthesis was inhibited with alpha-fluoromethylhistidine (3 mg.kg-1.h-1) given via osmotic minipumps over a period of 24 h. The treatment reduced the histidine decarboxylase activity (approximately 20% remaining) and histamine concentration (less than 20% remaining) in the oxyntic mucosa, as well as the intensity of histamine- and chromogranin A-immunostaining in the ECL cells, compared to control rats. The cytoplasmic (secretory) granules/vesicles were greatly reduced in number and size following alpha-fluoromethylhistidine administration. The histamine immunostaining of the mast cells, which occurs at the mucosal surface and in the submucosa, appeared unaffected. We conclude that ECL cell histamine accounts for at least 80% of the total oxyntic mucosal histamine in the rat and that it represents a more mobile pool than mast cell histamine. The reduction in the number and size of the ECL cell granules/vesicles following histamine depletion is in accord with the idea that they represent the storage site for histamine.
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PMID:Enterochromaffin-like cells in the rat stomach: effect of alpha-fluoromethylhistidine-evoked histamine depletion. A chemical, histochemical and electron-microscopic study. 138 83

Mast cells suppressed the proliferation of parenchymal liver cells (P-LC) in a dose-dependent manner, when they were cocultured with P-LC. On the contrary, mast cells activated by IgE and anti-IgE enhanced DNA synthesis of P-LC dose-dependently. The activity enhancing the proliferation of P-LC was found in the supernatant of the activated mast cells, but not in that of untreated mast cells, suggesting the secretion of active factors by active mast cells. Histamine, which are released by the activated mast cells, suppressed the enhancement of P-LC proliferation by activated mast cells. Since histamine and heparin did not effect the proliferation of P-LC directly, histamine may bring the suppression through regulating the activated mast cell. On the basis of these findings, we discuss the role of mast cells in liver regeneration.
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PMID:[Regulation of the cultured mouse parenchymal liver cells (P-LC) by mast cells]. 155 26

The effect of intracerebroventricularly (i.c.v.) administered histamine (100 micrograms/rat) on intestinal myoelectrical activity was investigated in the jejunum of fasted rats. Histamine caused the disappearance of phase III and a partial reduction of phase II of migrating myoelectric complexes. This effect was antagonized by i.c.v. pretreatment with mepyramine (10 micrograms/rat), an H1 receptor antagonist. Lesions of central noradrenergic neurons by i.c.v. injection of the neurotoxin 6-hydroxydopamine strongly reduced both the inhibition of intestinal propulsion and the migrating myoelectric complexes profile induced by i.c.v. histamine, whereas pretreatment with p-chlorophenylalanine, a selective depletor of serotonin stores, had no effect. It thus appears that aminergic pathways are involved in the visceral effects of central histamine. Mepyramine (200 micrograms/rat i.c.v.) partially reduced the slowing of intestinal transit induced by high doses of morphine. Pretreatment with compound 48/80 (10 micrograms/rat i.c.v.), a mast cell degranulator, but not with alpha-fluoromethylhistidine, an irreversible inhibitor of histidine decarboxylase, reduced the antipropulsive action of i.c.v. morphine to the same extent as mepyramine, suggesting that histamine released from cerebral mast cells by high doses of morphine could contribute to the intestinal inhibition by morphine.
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PMID:Further investigations on the antipropulsive effect of centrally administered histamine and its relation with morphine. 161 2

Phospholipase A2 activity in lysates of mast cells and their related cells [mouse bone marrow-derived IL-3 dependent mast cells (BMMC), rat connective tissue mast cells (CTMC), and rat mastocytoma RBL-2H3 cells] was measured using phosphatidylethanolamine (PE), phosphatidylserine (PS), and phosphatidylcholine (PC) as exogenous substrates. Both BMMC and RBL cells showed rather high phospholipase A2 activity, whereas CTMC showed only weak activity. These cells contained at least three types of phospholipase A2. Type 1 enzyme showed no appreciable affinity to heparin, and preferentially hydrolyzed either PC or PE, both of which have an arachidonic acid at the sn-2 position. The activity was absorbed by monoclonal antibody against rabbit platelet cytosolic 85-kDa phospholipase A2. Type 2 enzyme had an affinity to heparin, and was completely inhibited by anti-rat platelet 14-kDa secretory phospholipase A2. This enzyme could be expressed as an "ecto-type" enzyme on the cell surface and might be secreted from cells when mast cells are activated. Type 3 enzyme also had an affinity to heparin, but was separated from type 2 enzyme on reverse-phase HPLC. This enzyme did not interact with anti-14-kDa secretory enzyme antibody. Purified type 3 enzyme (30-kDa) specifically hydrolyzed PS. p-Bromophenacylbromide inhibited all types of phospholipase A2, whereas mepacrine inhibited type 2 and type 3 enzymes, but not type 1 enzyme. Type 2 enzyme was also inhibited by the specific antibody, complement degradation product, and a small-molecular-weight inhibitor. Histamine release was inhibited by all these inhibitors, whereas PGD2 production was inhibited only by p-bromophenacylbromide. Possible roles for these phospholipases A2 in mast cell function are proposed.
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PMID:Characteristics and possible functions of mast cell phospholipases A2. 163 97

1. Mast cell activation in the lung was investigated by measuring concentrations of mast cell tryptase and histamine in the bronchoalveolar lavage fluid from patients with bronchial carcinoma, sarcoidosis, extrinsic allergic alveolitis or cryptogenic fibrosing alveolitis and from normal subjects. 2. Histamine concentrations in bronchoalveolar lavage fluid supernatants were elevated in the bronchial carcinoma and cryptogenic fibrosing alveolitis groups, and were correlated with the histamine content of the cells recovered. 3. An avidin-biotin-enhanced antigen-capture e.l.i.s.a., using polyclonal rabbit antibody specific for tryptase, and mouse monoclonal antibody AA5, allowed the quantification of tryptase in all samples of bronchoalveolar lavage fluid. Tryptase concentrations were increased in the bronchial carcinoma and extrinsic allergic alveolitis groups and in some of the patients with sarcoidosis, and the levels correlated with mast cell numbers and also with concentrations of albumin. 4. There was no significant correlation between levels of tryptase and histamine, suggesting differences in the rates of metabolism or different cellular sources. 5. The tryptase and histamine concentrations measured suggest that there is continuous degranulation of mast cells within the normal lung, but that this process is more pronounced in patients with bronchial carcinoma or interstitial lung disease.
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PMID:Mast cell tryptase and histamine concentrations in bronchoalveolar lavage fluid from patients with interstitial lung disease. 165 61

The IV injection of neurotensin (NT) into anesthetized rats produced a marked increase in hematocrit, labored breathing and peripheral blood stasis with cyanosis. This effect could also be produced by the NT-related peptides, neuromedin-N and xenopsin; however, it was not observed when nine other biologically active peptides, including bradykinin and substance P, were tested. Associated with these responses were increases in the plasma levels of histamine (measured radioenzymatically) and the leukotrienes, LTB4, LTC4, LTD4, and LTE4 (measured by RIA and HPLC). The increment in hematocrit after varying doses of NT correlated to the increase in plasma levels of LTC4. Histamine and LTC4 were both capable of elevating hematocrit when given IV; however, LTC4 was approximately 1000 times more potent than histamine and active doses of histamine elevated LTC4 levels. Furthermore, the effects of NT on plasma LTC4 and hematocrit were reduced by pretreating animals with antagonists to histamine and serotonin. Pretreatment with the specific mast cell degranulating agent, compound 48/80, also blocked NT's ability to elevate plasma levels of histamine, LTB4 and LTC4 and prevented the increased hematocrit and cyanosis. These results indicate that NT-related peptides are very potent and specific stimulators of leukotriene release and that this action is mediated by mast cells and associated with loss of plasma volume and blood stasis. A working hypothesis is that histamine, released from mast cells in response to NT, stimulates LTC4 production by other cells.
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PMID:Neurotensin elevates hematocrit and plasma levels of the leukotrienes, LTB4, LTC4, LTD4 and LTE4, in anesthetized rats. 166 83


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