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)

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

Acid back diffusion into the rat stomach mucosa leads to gastric vasodilation. We hypothesized that histamine, if released from the rat mucosa under such conditions, is mast cell derived and involved in the vasodilator response. Gastric blood flow (GBF) and luminal histamine were measured in an ex vivo chamber. Venous histamine was measured from totally isolated stomachs. Mucosal mast cells (MMC), submucosal connective tissue mast cells (CTMC), and chromogranin A-immunoreactive cells (CgA IR) were assessed morphometrically. After mucosal exposure to 1.5 M NaCl, the mucosa was subjected to saline at pH 5.5 (control) or pH 1.0 (H(+) back diffusion) for 60 min. H(+) back diffusion evoked a marked gastric hyperemia, increase of luminal and venous histamine, and decreased numbers of MMC and CTMC. CgA IR cells were not influenced. Depletion of mast cells with dexamethasone abolished (and stabilization of mast cells with ketotifen attenuated) both hyperemia and histamine release in response to H(+) back diffusion. GBF responses to H(+) back diffusion were attenuated by H(1) and abolished by H(3) but not H(2) receptor blockers. Our data conform to the idea that mast cells are involved in the gastric hyperemic response to acid back diffusion via release of histamine.
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PMID:Mast cells are involved in the gastric hyperemic response to acid back diffusion via release of histamine. 1135 97

In the human adrenal cortex, serotonin (5-HT) is contained in mast-like cells, and we have shown that 5-HT stimulates aldosterone secretion, suggesting that 5-HT may control glomerulosa cells through a paracrine mechanism. Concurrently, the presence of 5-hydroxyindolacetic acid in human adrenocortical extracts indicates that 5-HT may be metabolized after local release by mast cells. The aim of the present study was to investigate in vitro the production and metabolism of 5-HT by the human adrenal cortex. Perifused adrenal slices released spontaneously detectable amounts of 5-HT (0.74 +/- 0.38 fmol/mg wet tissue.min). The mast cell-depleting drug compound 48/80 induced a burst of 5-HT secretion followed by a gradual increase in aldosterone production. Administration of the specific 5-HT(4) receptor antagonist GR 113808 (10(-6) M) did not affect compound 48/80-induced 5-HT release but abolished the stimulatory effect of compound 48/80 on aldosterone secretion, indicating that 5-HT released locally is responsible for a paracrine control of steroidogenesis. Incubation of cells from the human adrenal cortex with 5-HT (10(-5) M) provoked the formation of the 5-HT metabolite 5-hydroxytryptophol. The type A monoamine oxidase (MAO) inhibitor clorgyline (10(-6) M) suppressed the metabolism of 5-HT into 5-hydroxytryptophol. Immunocytochemical staining of cultured cells revealed the presence of a subpopulation of MAO-A-positive cells. Double labeling with an antiserum against chromogranin A showed that MAO-A was actually contained in chromaffin cells. Similarly, immunohistochemical staining of adrenal slices showed that MAO-A was expressed in chromaffin cells located both in the medulla and in intracortical rays. In conclusion, the present study shows that, in the human adrenal cortex, 5-HT, released by mast-cells, may stimulate aldosterone secretion in a paracrine manner. Our data also indicate that 5-HT is metabolized by MAO-A located in intracortical chromaffin cells.
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PMID:Production and metabolism of serotonin (5-HT) by the human adrenal cortex: paracrine stimulation of aldosterone secretion by 5-HT. 1160 May 77

We report the morphological characteristics of 30 cases of sclerosing hemangioma (SH) of the lung and explore the histological origin of the major cells in these tumors. In addition to routine light and electron microscopy, immunohistochemistry was performed by using 12 monoclonal primary and 5 polyclonal primary antibodies. These included surfactant protein B (SP-B), thyroid transcription factor-1 (TTF-1), mast cell trypsin, CD68, epithelial antigen markers (high molecular weight cytokeratin, low molecular weight cytokeratin [CK-L], epithelial membrane antigen [EMA], cancer embryonic antigen), mesothelial antigen, neuroendocrine markers (neuron-specific enolase [NSE], chromogranin A, synaptophysin, calcitonin, adrenocorticotropic hormone, human growth hormone [hHG]), vimentin, and CD34. Surface cuboidal cells have short microvilli and have lamellar bodies in their cytoplasm. They can sometimes merge into multinuclear giant cells. Immunohistochemical results showed that these cells are strongly positive for SP-B, TTF-1, CK-L, EMA, and cancer embryonic antigen, whereas polygonal cells, previously also described as round or pale cells, were strongly positive for vimentin and TTF-1, and positive or weakly positive for 2 to 3 kinds of neuroendocrine markers. Sparse neuroendocrine granules and abundant microfilaments were observed in their cytoplasm. Some cell clusters in the solid regions were positive for SP-B and EMA. Mast cells existed sparsely in almost every field. Both cuboidal and polygonal cells were negative to CD34 and mesothelial antigen staining. We conclude that cuboidal cells of SH originate from reactive proliferating type II pneumocytes, which can fuse into multinuclear giant cells. Polygonal cells, as true tumor cells, likely originate from multipotential primitive respiratory epithelium and possess the capability for multipotential differentiation. The antibodies of SP-B, TTF-1, vimentin, and CK-L are very helpful to diagnosis and differential diagnosis of SH.
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PMID:Immunohistochemical and ultrastructural markers suggest different origins for cuboidal and polygonal cells in pulmonary sclerosing hemangioma. 1511 33

Diagnosis of mast cell activation disease (MCAD), i.e. systemic mastocytosis (SM) and idiopathic systemic mast cell activation syndrome (MCAS), usually requires demonstration of increased mast cell (MC) mediator release. Since only a few MC mediators are currently established as biomarkers of MCAD, the sensitivity of plasma heparin level (pHL) as an indicator of increased MC activation was compared with that of serum tryptase, chromogranin A and urinary N-methylhistamine levels in 257 MCAD patients. Basal pHL had a sensitivity of 41% in MCAS patients and 27% in SM patients. Non-pharmacologic stimulation of MC degranulation by obstruction of venous flow for 10 minutes increased the sensitivity of pHL in MCAS patients to 59% and in SM patients to 47%. In MCAS patients tryptase, chromogranin A, and N-methylhistamine levels exhibited low sensitivities (10%, 12%, and 22%, respectively), whereas sensitivities for SM were higher (73%, 63%, and 43%, respectively). Taken together, these data suggest pHL appears more sensitive than the other mediators for detecting systemic MC activity in patients with MCAS. The simple, brief venous occlusion test appears to be a useful indicator of the presence of pathologically irritable MCs, at least in the obstructed compartment of the body.
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PMID:Determination of plasma heparin level improves identification of systemic mast cell activation disease. 2590 62