MESECLAZONE, 5-CHLOROSALICYLIC ACID AND ACETYLSALICYLIC-ACID - COMPARISON OF THEIR EFFECTS ON INVITRO AND EXVIVO PLATELET-AGGREGATION

  • 1 January 1978
    • journal article
    • research article
    • Vol. 40  (1) , 24-36
Abstract
Meseclazone and its major metabolite, 5-chlorosalicylic acid (5-CSA) possess anti-inflammatory, analgesic and antipyretic activity. The comparative effects of these compounds on platelet aggregation were evaluated in vitro and ex vivo with acetylsalicylic acid (ASA). In vitro, meseclazone and ASA exhibited almost identical inhibitory potency of secondary phase ADP aggregation while 5-CSA was less effective. Collagen aggregation was inhibited by all 3 agents: ASA > meseclazone > 5-CSA. Thrombin-induced aggregation was inhibited to approximately the same extent by 5-CSA and ASA while meseclazone was inactive. The in vitro effects on the release-inducing aggregants were confirmed by ex vivo experiments in rats. ASA and meseclazone inhibited collagen-induced aggregation 1 and 4 h after oral administration although ASA was 3-4 times more active. ASA, but not meseclazone, was still effective 24 h after administration. Bleeding times in rats 1 and 4 h following oral administration of meseclazone and ASA were not altered. Meseclazone and/or 5-CSA inhibit in vitro and ex vivo platelet aggregation initiated by the release reaction similar to ASA and other non-steroidal anti-inflammatory drugs.