The role of platelet-activating factor in cell infiltration in endotoxin-induced uveitis in guinea pigs.
OBJECTIVE
We investigated the role of platelet-activating factor (PAF) in cell infiltration in endotoxin-induced uveitis (EIU) in guinea pigs.


METHODS
To elicit EIU, lipopolysaccharide (LPS) was injected into the anterior chamber of the eye. Cell numbers in the aqueous humor after LPS injection were determined by flow cytometry. PAF and prostaglandin E2 (PGE2) production after LPS injection were also examined.


RESULTS
Intracameral injection of LPS induced cell infiltration into the anterior chamber, and platelet-activating factor (PAF) was detected in the aqueous humor. In addition, topical apafant (PAF antagonist) partially inhibited cell infiltration. Intracameral injection of PAF scarcely induced cell infiltration but the reaction with EIU was accelerated by intracameral injection of a small amount of PAF.


CONCLUSIONS
These results suggest that PAF has weak direct activity on cell infiltration in intraocular inflammation but enhances intraocular inflammation.
Tsuji
F
F
Discovery Research Division, Santen Pharmaceutical Co., Ltd., Osaka, Japan.
Shirasawa
E
E
D000818:Animals; D000867:Anterior Chamber / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D001082:Aqueous Humor / Q000378:metabolism; D001381:Azepines / Q000494:pharmacology; D001623:Betamethasone / Q000031:analogs & derivatives / Q000494:pharmacology; D002634:Chemotaxis, Leukocyte / Q000502:physiology*; D015232:Dinoprostone / Q000378:metabolism; D004926:Escherichia coli; D005434:Flow Cytometry; D006168:Guinea Pigs; D007213:Indomethacin / Q000494:pharmacology; D007958:Leukocyte Count; D007962:Leukocytes / Q000502:physiology*; D008070:Lipopolysaccharides / Q000633:toxicity*; D008297:Male; D009883:Ophthalmic Solutions; D010972:Platelet Activating Factor / Q000494:pharmacology / Q000502:physiology*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology; D014230:Triazoles / Q000494:pharmacology; D014606:Uveitis, Anterior / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology
D001381:Azepines; D008070:Lipopolysaccharides; D009883:Ophthalmic Solutions; D010972:Platelet Activating Factor; D010975:Platelet Aggregation Inhibitors; D014230:Triazoles; C052518:WEB 2086; C028994:betamethasone sodium phosphate; D001623:Betamethasone; D015232:Dinoprostone; D007213:Indomethacin