degranulation

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de·gran·u·la·tion

(dē-gran'yū-lā'shŭn),
Disappearance or loss of cytoplasmic granules from a cell or activation of granulocytic cells (for example, neutrophils, mast cells, basophils, eosinophils).
Farlex Partner Medical Dictionary © Farlex 2012

degranulation

(dē-grăn′yə-lā′shən)
n.
The process of losing granules.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.
References in periodicals archive ?
Upon activation, usually through recognition by toll-like receptors (TLRs), neutrophils can degranulate, releasing their granule content.
"The ear canal lining contains mast cells which degranulate (release granules) when exposed to an allergen.
The major components of honeybee venom are Mellitin, (a direct hemolysin, cytotoxic and cardiotoxic; is a protein that hydrolyzes cell membranes, alters cellular permeability and causes histamine release and also responsible for local pain), Phospholipase [A.sub.2] (the major allergenic component and causes intravascular hemolysis), Peptide 401 (or mast cell degranulating peptide-causes mast cells to degranulate, releasing histamine and vasoactive amines), Apamin (a neurotoxin that acts on spinal cord), Adolapin (inhibits prostaglandin synthetase and Hyaluronidase (causes changes in cell permeability by altering cell membranes and disrupts collagen, allowing other venom components to penetrate into victim's tissues).
Packed with granules of histamine, heparin and other chemical mediators, mast cells degranulate, releasing their contents, in response to the presence of allergens.
Signal 3 tolerant CD8 T cells degranulate in response to antigen but lack granzyme B to mediate cytolysis.
These findings suggest that autoantibodies such as IgE anti-dsDNA and IgE autoantibodies against thyroid peroxidase (TPO) can also activate basophils to degranulate and play substantial roles in the pathogenesis of CSU.
There are some studies demonstrating that PLTs increase in the course of inflammation and they degranulate in the infectious situations [31].
In the premalignant early phase of hyperplasia and dysplasia, infiltratingmast cells degranulate and activate dermal fibroblasts which intensify angiogenesis.
"The ear canal lining contains mast cells which degranulate [release granules] when exposed to an allergen.
Moreover, the functional response of mast cells depends on the stimuli received [12]; for example, following classical activation via the IgE receptor, Fc[epsilon]R1, mast cells degranulate rapidly (within minutes) to exocytose prostaglandins and leukotrienes as well as preformed cytokines, tryptase, histamine, heparin, and platelet activating factor (PAF) whilst de novo synthesised cytokines exhibit a more delayed (hours) release [8, 21].
It seems possible that substances which degranulate mast cells are capable of inducing migraine attacks without clear experimental evidence (1).
The failure of fentanyl to degranulate mast cells and antagonism of the fentanyl wheal and flare responses by naloxone led Levy et al (69) to suggest that the fentanyl-induced skin reactions are the result of direct opioid-mediated capillary vasodilation, unlike morphine's effect, which involves both histamine release and a direct opioid effect and therefore, "attempts to antagonize the adverse haemodynamic effects of histamine-releasing opioids with antihistamines will not be completely effective due to direct vascular responses".