-
J. Allergy Clin. Immunol. · Nov 2004
Protein kinase Cdelta functions downstream of Ca2+ mobilization in FcepsilonRI signaling to degranulation in mast cells.
- Sung-Hoon Cho, Chang-Hoon Woo, Seog-Beom Yoon, and Jae-Hong Kim.
- School of Life Sciences and Biotechnology, Korea University, 5-1 Anam-dong, Sungbuk-gu, Seoul 136-701, Korea.
- J. Allergy Clin. Immunol. 2004 Nov 1; 114 (5): 1085-92.
BackgroundMobilization of Ca 2+ plays an important role in the degranulation of mast cells. Although events upstream of Ca 2+ mobilization in the regulation of degranulation are relatively well characterized, the downstream mediators of Ca 2+ remain largely unknown.ObjectiveWe sought to characterize the downstream signaling mechanism by which Ca 2+ mobilization mediates degranulation in antigen-stimulated mast cells.MethodsThe effect of various inhibitors was examined in the antigen-induced or Ca 2+ ionophore A23187-induced degranulation process, and the effect of inhibitors on histamine release was tested in the mouse model of asthma.ResultsThe delta isoform of protein kinase C (PKC) functions downstream of Ca 2+ in the signaling pathway from FcepsilonRI to degranulation in RBL-2H3 mast cells. Stimulation of cells with either antigen or the Ca 2+ ionophore A23187 induced a rapid translocation of PKC-delta from the cytosol to the cellular membranes, and either treatment with the PKC-delta-specific inhibitor rottlerin or infection with an adenovirus encoding a dominant negative mutant of PKC-delta markedly inhibited degranulation induced with antigen or A23187. Furthermore, both the translocation of PKC-delta and degranulation induced by A23187 were inhibited by prevention of the accumulation of reactive oxygen species normally elicited by the ionophore. Finally, intraperitoneal injection of rottlerin prevented the increase in the concentration of histamine in bronchoalveolar lavage fluid induced by means of antigen challenge in a mouse model of allergic asthma. conclusion: PKC-delta plays an essential downstream mediatory role in the degranulation elicited by Ca 2+ mobilization, and reactive oxygen species mediate the activation of PKC-delta by Ca 2+ in the regulation of degranulation.
Notes
Knowledge, pearl, summary or comment to share?You can also include formatting, links, images and footnotes in your notes
- Simple formatting can be added to notes, such as
*italics*
,_underline_
or**bold**
. - Superscript can be denoted by
<sup>text</sup>
and subscript<sub>text</sub>
. - Numbered or bulleted lists can be created using either numbered lines
1. 2. 3.
, hyphens-
or asterisks*
. - Links can be included with:
[my link to pubmed](http://pubmed.com)
- Images can be included with:
![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
- For footnotes use
[^1](This is a footnote.)
inline. - Or use an inline reference
[^1]
to refer to a longer footnote elseweher in the document[^1]: This is a long footnote.
.