title: Vernolepin: an antiplatelet compound of natural origin.
abstract: Vernolepin, a natural compound isolated from Vernonia amygdalina Del., shows platelet anti-aggregating properties. In this paper some of its pharmacological activities towards rabbit platelets are studied. Vernolepin has a "stabilizing" effect during freeze-thawing of platelets, it inhibits arachidonic acid, ADP and collagen-induced platelet aggregation and interferes with ATP-release. Electromicroscopy shows a protection of platelets by the drug against adhesion and a desaggregating effect. All these activities are time dependent; a steep dose response relationship is seen. A concentration of 1 X 10(-5) g/ml seems to be optimal.
mesh_terms: D000244:Adenosine Diphosphate / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000494:pharmacology; D001792:Blood Platelets / Q000187:drug effects* / Q000648:ultrastructure; D003094:Collagen / Q000494:pharmacology; D005615:Freezing; D005976:Glutaral / Q000494:pharmacology; D066298:In Vitro Techniques; D008854:Microscopy, Electron; D010974:Platelet Aggregation / Q000187:drug effects*; D011817:Rabbits; D012717:Sesquiterpenes / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D001095:Arachidonic Acids; D012717:Sesquiterpenes; D016718:Arachidonic Acid; D000244:Adenosine Diphosphate; C036639:vernolepin; D000255:Adenosine Triphosphate; D003094:Collagen; D005976:Glutaral