TY - JOUR T1 - MODIFICATION OF THE FATTY ACID-INDUCED THROMBOCYTOPENIA BY ANTICOAGULANTS AND COMPOUNDS WHICH INHIBIT <em>IN VITRO</em> PLATELET AGGREGATION JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 163 LP - 171 VL - 159 IS - 1 AU - Gerhard Zbinden Y1 - 1968/01/01 UR - http://jpet.aspetjournals.org/content/159/1/163.abstract N2 - In an effort to characterize further potential antithrombotic effects of compounds which inhibit platelet aggregation and adhesiveness in vitro, an animal assay system was developed in which the acute and reversible thrombocytopenia following i.v. injection of 2.5 mg/kg of Na laurate was compared in drug-treated and untreated rabbits. Among several antihistamines, antiserotonins, tranquilizing and antinflammatory drugs known to inhibit adenosine diposphate-induced platelet clumping in vitro, only phenylbutazone inhibited Na laurate-induced thrombocytopenia. Large doses were necessary and the effect was not consistent. Three anticoagulants, heparin, bishydroxycoumarin and a new, synthetic heparinoid, Ro 2-7509, inhibited the thrombocytopenic response, but only at doses which also affected blood clotting. Na laurate given after large doses of heparin or Ro 2-7509 often caused platelet clumping, which may be a manifestation of certain thrombogenic properties of the two anticoagulants. Adenosine triphosphate and adenosine monophosphate had no effect on Na laurate-induced thrombocytopenia. Adenosine triphosphate itself caused significant decrease in platelet counts, probably because of its conversion to adenosine diphosphate. It is suggested that the Na laurate-induced thrombocytopenia represents an early and mostly reversible stage of thrombosis which can be influenced by drugs known to have a beneficial effect in thromboembolism in man. © 1968 by The Williams &amp; Wilkins Company ER -