title: Inhibitory effects of a novel platelet activating factor (PAF) antagonist (BN 52021) on antigen-induced prostaglandin and thromboxane formation by the guinea pig lung.
abstract: The effects of a new Platelet-Activating Factor (PAF-acether) antagonist (BN 52021) extracted from Ginkgo biloba leaves have been studied on the release of metabolites of arachidonic acid in IgG-dependent guinea pig pulmonary anaphylaxis in vitro. Prostaglandin E2 (PGE2) and thromboxane B2 (TxB2) were assayed using a novel ELISA technique. The release of PGE2 and TxB2 from anaphylactic lungs reached a maximum 4-5 min following the antigen challenge (about 3.2 and 31.0 ng/ml respectively) and decayed slowly during the following 25 min. BN 52021 (1, 3 and 30 micrograms/ml) produced dose-dependent decreases of the release of PGE2 and TxB2. These results suggest that there are some interactions between the release of icosanoids and PAF-acether in anaphylaxis.
mesh_terms: D000707:Anaphylaxis / Q000378:metabolism; D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism; D015232:Dinoprostone; D004224:Diterpenes; D005260:Female; D046934:Ginkgolides; D006168:Guinea Pigs; D066298:In Vitro Techniques; D007700:Kinetics; D007783:Lactones; D008168:Lung / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D010047:Ovalbumin / Q000494:pharmacology; D010936:Plant Extracts / Q000494:pharmacology*; D010972:Platelet Activating Factor / Q000037:antagonists & inhibitors*; D011453:Prostaglandins / Q000096:biosynthesis*; D011458:Prostaglandins E / Q000494:pharmacology; D013929:Thromboxane B2 / Q000494:pharmacology; D013931:Thromboxanes / Q000096:biosynthesis*
chemical_list: D001095:Arachidonic Acids; D004224:Diterpenes; D046934:Ginkgolides; D007783:Lactones; D010936:Plant Extracts; D010972:Platelet Activating Factor; D011453:Prostaglandins; D011458:Prostaglandins E; D013931:Thromboxanes; D016718:Arachidonic Acid; D013929:Thromboxane B2; D010047:Ovalbumin; C045856:ginkgolide B; D015232:Dinoprostone