title: Antiplatelet effects of Cyperus rotundus and its component (+)-nootkatone.
abstract: BACKGROUND
  Cyperus rotundus, a well-known oriental traditional medicine, has been reported to exhibit wide spectrum activity in biological systems including the circulatory system, however, little information is available on its antiplatelet activity. This study was undertaken to investigate the antiplatelet effects of Cyperus rotundus EtOH extract (CRE) and its constituent compounds.
  
  
  METHODS
  The antiplatelet activities of CRE and its eight constituent compounds were evaluated by examining their effects on rat platelet aggregations in vitro and ex vivo, and on mice tail bleeding times.
  
  
  RESULTS
  During the in vitro platelet aggregation study, CRE showed significant and concentration-dependent inhibitory effects on collagen-, thrombin-, and/or AA-induced platelet aggregation. Of its eight components, (+)-nootkatone was found to have the most potent inhibitory effect on collagen-, thrombin-, and AA-induced platelet aggregation. In addition, CRE- and (+)-nootkatone-treated mice exhibited significantly prolonged bleeding times. Furthermore, (+)-nootkatone had a significant inhibitory effect on rat platelet aggregation ex vivo.
  
  
  CONCLUSIONS
  This study demonstrates the antiplatelet effects of CRE and its active component (+)-nootkatone, and suggests that these agents might be of therapeutic benefit for the prevention of platelet-associated cardiovascular diseases.
authors.affiliation: Department of Physiology, Ajou University School of Medicine, Suwon 443-749, Republic of Korea.
authors.forename: Eun Ji
authors.initials: EJ
authors.lastname: Seo
authors.forename: Dong-Ung
authors.initials: DU
authors.lastname: Lee
authors.forename: Jong Hwan
authors.initials: JH
authors.lastname: Kwak
authors.forename: Sun-Mee
authors.initials: SM
authors.lastname: Lee
authors.forename: Yeong Shik
authors.initials: YS
authors.lastname: Kim
authors.forename: Yi-Sook
authors.initials: YS
authors.lastname: Jung
mesh_terms: D000818:Animals; D016718:Arachidonic Acid; D001760:Bleeding Time; D003094:Collagen; D029786:Cyperus / Q000737:chemistry*; D051379:Mice; D008813:Mice, Inbred ICR; D010936:Plant Extracts / Q000494:pharmacology*; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D000081223:Polycyclic Sesquiterpenes; D051381:Rats; D017207:Rats, Sprague-Dawley; D012717:Sesquiterpenes / Q000494:pharmacology*; D013917:Thrombin
chemical_list: D010936:Plant Extracts; D010975:Platelet Aggregation Inhibitors; D000081223:Polycyclic Sesquiterpenes; D012717:Sesquiterpenes; D016718:Arachidonic Acid; D003094:Collagen; D013917:Thrombin; C050302:nootkatone