title: [Effect of a new thromboxane A2 antagonist, S-145, on platelet aggregation].
abstract: The newly synthesized compound S-145, (+/-)-5(Z)-7-(3-endo-phenylsulfonylamino [2.2.1] bicyclohept-2-exo-yl)heptenoic acid, inhibited arachidonic acid (AA)-, 9,11-methanoepoxy-PGH2 (U46619)-, collagen- and ADP-induced human platelet aggregation in vitro with IC50 values of 0.25, 0.34, 0.22, and 0.08 microM, respectively. The inhibiting potency of this compound to AA- or U46619-induced platelet aggregation was about twice that of ONO-3708 and 1/7-1/14 that of SQ29,548 in human platelets, about 7 times that of ONO-3708 and 1/3-1/7 that of SQ29,548 in guinea pig platelets, and 250-800 times that of ONO-3708 and 1-7 times that of SQ29,548 in rabbit platelets. When S-145 was administered orally to guinea pigs at the dose of 0.1 mg/kg, AA-induced platelet aggregation was completely inhibited at 30 and 60 min after the administration, but not at 3 and 6 hr. The minimum effective doses of S-145 (p.o.) to AA- and collagen-induced platelet aggregation at 60 min after the administration were 0.01 mg/kg and 0.03 mg/kg, respectively. The potency of S-145 (p.o.) to inhibit AA- and collagen-induced guinea pig platelet aggregation was 30-300 times that of ONO-3708 or SQ29,548 and 300-1000 times that of aspirin. These results suggest that S-145 is a thromboxane A2 antagonist showing a potent inhibiting effect on platelet aggregation by oral administration.
authors.affiliation: Shionogi Research Laboratories, Shionogi & Co., Ltd., Osaka, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kakushi
authors.forename: T
authors.initials: T
authors.lastname: Shike
authors.forename: K
authors.initials: K
authors.lastname: Uchida
mesh_terms: D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; D000244:Adenosine Diphosphate / Q000037:antagonists & inhibitors; D000284:Administration, Oral; D000328:Adult; D000818:Animals; D001095:Arachidonic Acids / Q000037:antagonists & inhibitors; D001643:Bridged Bicyclo Compounds / Q000008:administration & dosage / Q000494:pharmacology*; D019086:Bridged Bicyclo Compounds, Heterocyclic; D001952:Bridged-Ring Compounds / Q000494:pharmacology*; D003094:Collagen / Q000037:antagonists & inhibitors; D005229:Fatty Acids, Monounsaturated / Q000008:administration & dosage / Q000494:pharmacology*; D005231:Fatty Acids, Unsaturated; D006168:Guinea Pigs; D006801:Humans; D006834:Hydrazines / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D011450:Prostaglandin Endoperoxides, Synthetic / Q000037:antagonists & inhibitors; D011817:Rabbits; D013928:Thromboxane A2 / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors* / Q000494:pharmacology
chemical_list: D001095:Arachidonic Acids; D001643:Bridged Bicyclo Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D001952:Bridged-Ring Compounds; D005229:Fatty Acids, Monounsaturated; D005231:Fatty Acids, Unsaturated; D006834:Hydrazines; D010975:Platelet Aggregation Inhibitors; D011450:Prostaglandin Endoperoxides, Synthetic; C056566:S 145; D013928:Thromboxane A2; D000244:Adenosine Diphosphate; D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; C045749:SQ 29548; C049855:ONO 3708; D003094:Collagen