The effect of Paf antagonists on bronchial hyperresponsiveness induced by Paf, propranolol or indomethacin.
1. Intravenous administration of platelet activating factor, Paf (600 ng kg-1 h-1) to ventilated anaesthetised guinea-pigs induced bronchial hyperresponsiveness to i.v. acetylcholine. 2. Pretreatment of ventilated, anaesthetised guinea-pigs with the beta-adrenoceptor antagonist, propranolol, or the non-steroidal anti-inflammatory drug, indomethacin, induced bronchial hyperresponsiveness to i.v. histamine. 3. Paf-induced bronchial hyperresponsiveness was significantly attenuated by pretreatment with three different Paf antagonists, CV-3988, BN 52021 and WEB 2086. 4. Pretreatment of guinea-pigs with CV-3988, BN 52021 or WEB 2086 at doses inhibiting Paf-induced bronchial hyperresponsiveness, had no significant effect on propranolol or indomethacin-induced bronchial hyperresponsiveness. 5. It is suggested that bronchial hyperresponsiveness induced by propranolol or indomethacin is not secondary to Paf release in the guinea-pig.
Department of Pharmacology, King's College, London University.
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Dixon
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Wilsoncroft
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Robertson
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D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001381:Azepines / Q000494:pharmacology; D001980:Bronchi / Q000187:drug effects*; D004224:Diterpenes; D046934:Ginkgolides; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology*; D007783:Lactones / Q000494:pharmacology; D008297:Male; D010742:Phospholipid Ethers / Q000494:pharmacology; D010972:Platelet Activating Factor / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology*; D012130:Respiratory Hypersensitivity / Q000503:physiopathology*; D014227:Triazines / Q000494:pharmacology; D014230:Triazoles
D001381:Azepines; D004224:Diterpenes; D046934:Ginkgolides; D007783:Lactones; D010742:Phospholipid Ethers; D010972:Platelet Activating Factor; D014227:Triazines; D014230:Triazoles; C052518:WEB 2086; D006632:Histamine; C037913:CV 3988; D011433:Propranolol; C045856:ginkgolide B; D000109:Acetylcholine; D007213:Indomethacin