title: Arginine inhibits hemostasis activation.
abstract: BACKGROUND
  The diagnosis and the therapy of in vivo hemostasis activation is of great clinical importance. Artefactual changes of the hemostasis (i.e., coagulation or fibrinolysis) in vitro have to be prevented. Usual in vitro anticoagulation by sodium citrate does not fully inhibit coagulation--or fibrinolysis--activation. Therefore, there is need for a simple physiologic inhibitor of hemostasis activation both in diagnosis and therapy of hemostasis activation.
  
  
  METHODS
  Whole blood clotting time (WBCT), prothrombin time (PT), activated partial thromboplastin time (APTT), in vitro bleeding test closure time (IVBT-CT), and whole blood aggregometry (WBA) were determined in normal human blood or plasma, supplemented with increasing concentrations of L-arginine or guanidine.
  
  
  RESULTS
  Arginine in concentrations of 5-100 mM inhibited the WBCT, PT, APTT, IVBT-CT, and WBA. Arginine (50 mM) resulted in a two-fold prolongation of WBCT, PT, or IVBT-CT (the anti-epinephrine action is superior to the anti-ADP action), a four-fold prolongation of APTT or a 60% inhibition of WBA.
  
  
  CONCLUSIONS
  L-Arginine (or guanidine) inhibited the activation of hemostasis. Arginine might be used as hemostasis stabilizer both in the diagnosis and therapy of hemostasis activation. The usage of arginine as an in vitro hemostasis inhibitor might be indicated in the diagnosis of hemostasis activation, as occurring in pharmacological thrombolysis or disseminated intravascular coagulation (DIC). The storage of blood or blood products might be improved by arginine stabilization. The amino acid (and nitric oxide precursor) L-arginine could be an interesting new pharmacologic agent to inhibit a pathologic hemostasis activation.
authors.affiliation: Department of Clinical Chemistry and Molecular Diagnostics, Hospital of Philipps University, D-35033 Marburg, Germany. thstief@post.med.uni-marburg.de
authors.forename: T W
authors.initials: TW
authors.lastname: Stief
authors.forename: M
authors.initials: M
authors.lastname: Weippert
authors.forename: V
authors.initials: V
authors.lastname: Kretschmer
authors.forename: H
authors.initials: H
authors.lastname: Renz
mesh_terms: D001120:Arginine / Q000494:pharmacology*; D001773:Blood Cells / Q000187:drug effects; D001780:Blood Coagulation Tests; D001800:Blood Specimen Collection / Q000379:methods / Q000592:standards; D004305:Dose-Response Relationship, Drug; D006487:Hemostasis / Q000187:drug effects*; D006801:Humans; D010979:Platelet Function Tests
chemical_list: D001120:Arginine