Platelet-activating factor (PAF) induced cytokine production and otitis media with effusion (OME) in the rat middle ear.
OBJECTIVE
We examined the effect of platelet-activating factor (PAF) on IL-8 production in cultured rat middle ear epithelial cells (RMECs), and the concentrations of cytokine, PAF, and PAF-acetylhydrolase (PAF-AH) were also examined in the PAF-induced experimental OME (otitis media with effusion) of rats.


METHODS
Using an enzyme-linked immunospecific assay, we measured the levels of cytokines in the cultured RMECs and the PAF-induced OME of rats. The PAF was quantitated by the platelet-aggregating activity and the PAF-AH was measured by radioimmunoassay.


RESULTS
Both PAF and C-PAF, which is a stable analogue of PAF, significantly induced production of IL-8 in the RMECs in a dose-dependent manner. The PAF-induced IL-8 production was abolished by co-incubation with WEB2170, a specific PAF receptor antagonist. The concentrations of the cytokines and PAF in the PAF-induced OME of rats were higher on day 1 and the PAF and cytokine levels seemed to correspond well with the persistence of OME.


CONCLUSIONS
PAF may stimulate the local production of cytokines and may induce OME in the middle ear.
Ogura
Manabu
M
Department of Otolaryngology, Kansai Medical University, 2-3-1 Shinmachi, Hirakata, Osaka, Japan.
Furukawa
Masayuki
M
Tada
Naoki
N
Ikeda
Hiroki
H
Yamashita
Toshio
T
D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase / Q000378:metabolism; D000818:Animals; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004847:Epithelial Cells / Q000187:drug effects / Q000276:immunology; D066298:In Vitro Techniques; D016209:Interleukin-8 / Q000378:metabolism*; D008297:Male; D010034:Otitis Media with Effusion / Q000276:immunology*; D010972:Platelet Activating Factor / Q000378:metabolism / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D016209:Interleukin-8; D010972:Platelet Activating Factor; D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase