title: WEB 2347: pharmacology of a new very potent and long acting hetrazepinoic PAF-antagonist and its action in repeatedly sensitized guinea-pigs.
abstract: WEB 2347 is a new hetrazepine which is superior to the previously described paf-antagonists WEB 2086 (apafant) and WEB 2170 (bepafant). This refers to both potency in vitro and in vivo (particularly after oral administration: e.g. the ED50 after oral administration is about 100 times less for WEB 2347 than for WEB 2086 to antagonize paf-induced hypotension in the rat) and duration of action (t1/2 = 41 h in the guinea pig and about 10 h in the rat after p.o. administration). Furthermore the role of paf in active anaphylaxis in vivo, even after repeated microshock, is strengthened.
authors.affiliation: Department of Pharmacology, Boehringer Ingelheim KG, Ingelheim/Rhein, F.R.G.
authors.forename: H O
authors.initials: HO
authors.lastname: Heuer
mesh_terms: D000284:Administration, Oral; D000707:Anaphylaxis / Q000503:physiopathology; D000818:Animals; D001381:Azepines / Q000008:administration & dosage / Q000494:pharmacology*; D016084:Bronchoconstriction / Q000187:drug effects; D006168:Guinea Pigs; D007022:Hypotension / Q000503:physiopathology; D007114:Immunization / Q000379:methods; D010972:Platelet Activating Factor / Q000037:antagonists & inhibitors*; D010974:Platelet Aggregation / Q000187:drug effects; D011817:Rabbits; D051381:Rats; D011919:Rats, Inbred Strains; D013997:Time Factors; D014230:Triazoles / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D001381:Azepines; D010972:Platelet Activating Factor; D014230:Triazoles; C068034:WEB 2347; C063964:bepafant