title: Synergism of procoagulation effect of thrombin-like enzymes from Dienagkistrodon acutus and Agkistrodon halys snake venoms.
abstract: OBJECTIVE
  To study the synergistic effect of thrombin-like enzymes (TLE) of Dienagkistrodon acutus (DA) and Agkistrodon halys (AH) venoms.
  
  
  METHODS
  TLE were isolated from venoms of DA and AH by successive column chromatography. Effects of combination of DATLE and AHTLE and related factors on the clotting time and clot quality were tested in vitro.
  
  
  RESULTS
  One coagulation unit was 2.7 micrograms for DATLE and 304.4 micrograms, for AHTLE with reference standard of thrombin (42.2 micrograms). TLE-induced clot was a fibrin monomer which was fragile and did not retract. Combination of AHTLE and DATLE shortened the clotting time and decreased the solubility of the clot in urea 5 mol.L-1. When subthreshold concentration of thrombin or physiological concentration of Ca2+ was added, the clotting time was further shortened, the clot was no longer soluble in urea and retracted well, and the resistance of the clot to plasmin degradation was increased.
  
  
  CONCLUSIONS
  A synergistic effect of DATLE and AHTLE accelerated hemocoagulation and improve clot quality.
authors.affiliation: Department of Pharmacology, Sun Yat-Sen University of Medical Sciences, Guangzhou, China.
authors.forename: W L
authors.initials: WL
authors.lastname: Wei
authors.forename: J J
authors.initials: JJ
authors.lastname: Sun
authors.forename: J S
authors.initials: JS
authors.lastname: Chen
mesh_terms: D017836:Agkistrodon / Q000145:classification; D000818:Animals; D001777:Blood Coagulation / Q000187:drug effects; D001780:Blood Coagulation Tests; D003435:Crotalid Venoms / Q000737:chemistry*; D004285:Dogs; D004357:Drug Synergism; D006490:Hemostatics / Q000302:isolation & purification / Q000494:pharmacology*; D013917:Thrombin / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D003435:Crotalid Venoms; D006490:Hemostatics; D013917:Thrombin