Antigen challenge induces a supraglottic but not a subglottic edema in the rat larynx

2005 ◽  
Vol 132 (5) ◽  
pp. 694-700 ◽  
Author(s):  
Anders Niklasson ◽  
Åke Dahlqvist
Keyword(s):  
Electron Microscopy ◽  
Mast Cells ◽  
Connective Tissue ◽  
Light And Electron Microscopy ◽  
Allergen Challenge ◽  
Type I ◽  
Subglottic Region ◽  
Mucosal Mast Cells ◽  
Type I Hypersensitivity ◽  
Head Neck

OBJECTIVE: To examine the reaction of mast cells in the larynx of sensitized rats after allergen challenge and determine whether a type I hypersensitivity reaction can elicit a supraglottic and subglottic edema. STUDY DESIGN: Rats were sensitized with ovalbumin (OA) and challenged 3 weeks later by intravenous injection of either OA or NaCl and perfused with glutaraldehyde. The larynges were removed and processed for light and electron microscopy. Sections from the epiglottis and subglottic region were examined. RESULTS: In challenged animals, the connective tissue mast cells (CTMC) in the epiglottic submucosa, but not the mucosal mast cells (MMC) in epithelium, were significantly reduced compared with the case of controls, and the connective tissue was edematous. In the subglottic region, the number of both MMC and CTMC was reduced (albeit not significantly), and there was no edema in the lamina propria. CONCLUSIONS: Allergen challenge induces a marked edema in the epiglottis but not in the subglottic area. SIGNIFICANCE: The results indicate that the supraglottic and subglottic regions react differently to allergen challenge. (Otolaryngol Head Neck Surg 2005;132:694-700.)

Mast cell heterogeneity

1984 ◽  
Vol 62 (6) ◽  
pp. 734-737 ◽  
Author(s):  
F. Shanahan ◽  
J. A. Denburg ◽  
J. Bienenstock ◽  
A. D. Befus
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Connective Tissue ◽  
Regulatory Peptides ◽  
Cell Heterogeneity ◽  
Cell Secretion ◽  
Biochemical Basis ◽  
Mucosal Mast Cells ◽  
Mast Cell Heterogeneity

Increasing evidence for the existence of inter- and intra-species mast cell heterogeneity has expanded the potential biological role of this cell. Early studies suggesting that mast cells at mucosal sites differ morphologically and histochemically from connective tissue mast cells have been confirmed using isolated intestinal mucosal mast cells in the rat and more recently in man. These studies also established that mucosal mast cells are functionally distinct from connective tissue mast cells. Thus, mucosal and connective tissue mast cells differ in their responsiveness to a variety of mast cell secretagogues and antiallergic agents. Speculation about the therapeutic use of antiallergic drugs in disorders involving intestinal mast cells cannot, therefore, be based on extrapolation from studies of their effects on mast cells from other sites. Regulatory mechanisms for mast cell secretion may also be heterogeneous since mucosal mast cells differ from connective tissue mast cells in their response to a variety of physiologically occurring regulatory peptides. The development of techniques to purify isolated mast cell sub-populations will facilitate future analysis of the biochemical basis of the functional heterogeneity of mast cells.

Mutual Phenotypic Changes between Connective Tissue Type and Mucosal Mast Cells

1987 ◽  
Vol 82 (3-4) ◽  
pp. 244-248 ◽  
Author(s):  
Yukihiko Kitamura ◽  
Yuzuru Kanakura ◽  
Sanae Sonoda ◽  
Hidekazu Asai ◽  
Toru Nakano
Keyword(s):  
Mast Cells ◽  
Connective Tissue ◽  
Tissue Type ◽  
Phenotypic Changes ◽  
Mucosal Mast Cells

The ultrastructure of the cardiac Purkinje strand in the dog: a morphometric analysis

1983 ◽  
Vol 217 (1207) ◽  
pp. 191-213 ◽  
Keyword(s):  
Electron Microscopy ◽  
Electrical Properties ◽  
Connective Tissue ◽  
Surface Area ◽  
Series Resistance ◽  
Membrane Surface ◽  
Light And Electron Microscopy ◽  
Total Surface Area ◽  
Membrane Surface Area ◽  
Extracellular Ions

Purkinje strands from both ventricles of adult mongrel dogs were excised, and electrical properties were studied by the voltage-clamp technique. The strands were then examined with light and electron microscopy and structural properties were analysed by morphometric techniques. The canine Purkinje strand contains (by volume) about 28% myocyte and 55% dense outer connective tissue. The remainder of the volume is taken up by the inner shell of loosely packed connective tissue within 10 μm of a myocyte membrane. These volume fractions vary considerably from one strand to another. Clefts less than 10 μm wide occupy 18% of the myocyte volume and clefts less than 1 μm wide occupy 1%. The membrane surface area of the myocytes can be divided into three categories by reference to the size of the adjacent cleft. About 47.8% of the membrane surface area faces clefts wider than 1 μm, another 22.2% faces clefts between 0.1 and 1 μm wide, and the final 30% faces clefts less than 0.1 μm wide. The surface area facing the narrowest clefts (less than 0.1 μm wide) is divided between nexuses 3%, desmosomes 10%, and unspecialized membrane 17% (each figure is expressed as a percentage of the total surface area of myocyte membrane). The canine Purkinje strand has a more favourable anatomy than the sheep Purkinje strand for most physiological experiments. We expect that the complicating effects of series resistance and change in the concentration of extracellular ions will be much smaller than in sheep strands, but still not negligible.

Observations on the nephridial system of the cestode Moniezia expansa (Rud., 1805)

Parasitology ◽  
1969 ◽  
Vol 59 (2) ◽  
pp. 449-459 ◽  
Author(s):  
R. E. Howells
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Epithelial Cells ◽  
Connective Tissue ◽  
Intercellular Space ◽  
Technical Assistance ◽  
Light And Electron Microscopy ◽  
Flame Cell ◽  
Research Scholarship ◽  
Research Facilities

The nephridial system of M. expansa has been studied using light and electron microscopy, and a number of histochemical techniques have been used on sections of the worm. The organization of the nephridial system and the fine structure of the flame cells and the nephridial ducts are described. Pores, which connect the nephridial lumen to the intercellular space of the connective tissue, exist at the junction of a flame cell and a nephridial duct. These pores may be considered nephrostomes and the system therefore is not protonephridial as defined by Hyman (1951).The epithelium lining the nephridial ducts has a structure which suggests that it is metabolically active. It is postulated that the beating of the cilia of the flame cells draws fluid into the ducts via the nephrostomes, with absorption and/or secretion of solutes being carried out by the epithelial cells of the duct walls. The function of the nephridial system is discussed.I am grateful to Professor James Brough for the provision of research facilities at the Department of Zoology, University College, Cardiff, andtoDrD. A. Erasmus for much helpful advice during the course of the work. I wish to thank Professors W. Peters and T. Wilson for critically reading the manuscript and Miss M. Williams and Mr T. Davies for expert technical assistance.I also wish to thank the Veterinary Inspector and his staff at the Roath Abattoir, Cardiff, for their kind co-operation and assistance in obtaining material.The work was carried out under the tenure of an S.R.C. research scholarship.

Morin inhibits Fyn kinase in mast cells and IgE-mediated type I hypersensitivity response in vivo

2009 ◽  
Vol 77 (9) ◽  
pp. 1506-1512 ◽  
Author(s):  
Jie Wan Kim ◽  
Jun Ho Lee ◽  
Bang Yeon Hwang ◽  
Se Hwan Mun ◽  
Na Young Ko ◽  
...  
Keyword(s):  
Mast Cells ◽  
Type I ◽  
Hypersensitivity Response ◽  
Fyn Kinase ◽  
Ige Mediated ◽  
Type I Hypersensitivity

The structure of the antennal heart of Aedes aegypti (Linnaeus)

1997 ◽  
Vol 75 (3) ◽  
pp. 444-458 ◽  
Author(s):  
B. D. Sun ◽  
J. M. Schmidt
Keyword(s):  
Electron Microscopy ◽  
Connective Tissue ◽  
Aedes Aegypti ◽  
Light And Electron Microscopy ◽  
Single Layer ◽  
Epidermal Cells ◽  
Muscle Fibres ◽  
Columnar Cells

The structure of the antennal heart of Aedes aegypti (L.) (Diptera: Culicidae) was observed using light and electron microscopy. The antennal heart consists of several distinct regions including a single layer of columnar cells, the chamber walls, the valve, the z-body, the muscle fibres, and the connective tissue filaments. The columnar cells are structurally similar to secretory and osmoregulatory cells. Features of tendinous epidermal cells typically involved in the attachment of muscles to the cuticle can be observed in various areas of the antennal heart when it is examined as a whole. A model describing the pumping mechanism of the antennal heart in A. aegypti is presented.

scholarly journals Signal Transduction Pathways Activated by Innate Immunity in Mast Cells: Translating Sensing of Changes into Specific Responses

Cells ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 2411 ◽  
Author(s):  
Zyanya P. Espinosa-Riquer ◽  
Deisy Segura-Villalobos ◽  
Itzel G. Ramírez-Moreno ◽  
Marian Jesabel Pérez Rodríguez ◽  
Mónica Lamas ◽  
...  
Keyword(s):  
Innate Immunity ◽  
Mast Cells ◽  
Signaling Pathways ◽  
Cell Lineage ◽  
Negative Control ◽  
Type I ◽  
Control Mechanisms ◽  
Cell Type ◽  
And Function ◽  
Type I Hypersensitivity

Mast cells (MCs) constitute an essential cell lineage that participates in innate and adaptive immune responses and whose phenotype and function are influenced by tissue-specific conditions. Their mechanisms of activation in type I hypersensitivity reactions have been the subject of multiple studies, but the signaling pathways behind their activation by innate immunity stimuli are not so well described. Here, we review the recent evidence regarding the main molecular elements and signaling pathways connecting the innate immune receptors and hypoxic microenvironment to cytokine synthesis and the secretion of soluble or exosome-contained mediators in this cell type. When known, the positive and negative control mechanisms of those pathways are presented, together with their possible implications for the understanding of mast cell-driven chronic inflammation. Finally, we discuss the relevance of the knowledge about signaling in this cell type in the recognition of MCs as central elements on innate immunity, whose remarkable plasticity converts them in sensors of micro-environmental discontinuities and controllers of tissue homeostasis.

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