six beta-adrenoceptor antagonists ( propranolol ( + and - isomers ) ; ici-118,551 ; oxprenolol ; timolol ; metoprolol ; and practolol ( + and - isomers ) , chosen to represent a spectrum of physicochemical and pharmacological properties , inhibited the response of human platelets to all aggregating agents tested . for any given aggregating agent the extent of inhibition correlated with the lipid solubility of the beta-adrenoceptor antagonist and showed no relation to other properties of these compounds . inhibition of aggregation by the beta-adrenoceptor antagonists was manifested as a parallel shift to the right in the dose-response curve . analysis of these data according to arunlakshana and schild ( br . j. pharmac . 14 , 48-58 ( 1969 ] showed a dependence of the apparent pa2 on the agonist employed and gave a slope approximating unity when adp , 9,11-epoxymethanoprostaglandin h2 ( u-46619 ) , adrenaline , 1-o-alkyl-2-acetyl-sn-glyceryl-3-phosphorylcholine ( paf ) or arachidonate were used as agonists .
C0086418
human
C0919509
h2