title: Intraspecies differences in hemostatic venom activities of the South American rattlesnakes, Crotalus durissus cumanensis, as revealed by a range of protease inhibitors.
abstract: Crotalus durissus cumanensis is an endemic rattlesnake found in Venezuela and Colombia. In this study, a comparative analysis of hemorrhagic, coagulation and fibrino(geno)lytic activities in the presence or absence of protease inhibitors was performed with venoms of the same species Crotalus durissus cumanensis, from seven geographical regions of Venezuela (Lagunetica, Santa Teresa, Carrizales, Guarenas, Anzoátegui, Margarita and Maracay). Lagunetica, Carrizales and Anzoátegui venoms induced hemorrhagic activity. All venoms, except that of snakes from the Carrizales region presented thrombin-like activity, which was inhibited completely by phenylmethanesulfonyl fluoride and ethylene glycol-bis-N, N,N',N'-tetraacetic acid. This effect of the latter could be explained by the high chelant calcium effect, which is a cofactor for the fibrin polymerization process. Soybean trypsin inhibitor was effective on Santa Teresa venom. Antithrombin III/Hep complex and phenantroline partially inhibited this activity in all venoms except Margarita and Anzoátegui, respectively, which were not inhibited. Serine protease inhibitors were more effective against thrombin, kallikrein and plasmin-like amidolytic activities. Additionally, metalloprotease inhibitors significantly inhibited the t-PA-like amidolytic activity and completely the hemorrhagic and fibrino(geno)lytic activities. In conclusion, the thrombin-like activity observed in these venoms was partially reduced by serine protease inhibitors, indicating the possible presence of catalytic domains in those enzymes that do not interact with these inhibitors. Using protease inhibitors on venom hemostatic activities could contribute to our understanding of the active components of snake venom on the hemostatic system, and further reveal the intraspecies variation of venoms, which is important in the treatment of envenomation, and in addition represents an interesting model for the study of venom in hemostasis.
authors.affiliation: Physiopathology Laboratory, Experimental Medicine Center, Venezuelan Institute of Scientific Research (IVIC), Venezuela.
authors.forename: Ana M
authors.initials: AM
authors.lastname: Salazar
authors.forename: Irma
authors.initials: I
authors.lastname: Aguilar
authors.forename: Belsy
authors.initials: B
authors.lastname: Guerrero
authors.forename: María E
authors.initials: ME
authors.lastname: Girón
authors.forename: Sara
authors.initials: S
authors.lastname: Lucena
authors.forename: Elda E
authors.initials: EE
authors.lastname: Sánchez
authors.forename: Alexis
authors.initials: A
authors.lastname: Rodríguez-Acosta
mesh_terms: D000818:Animals; D000991:Antithrombins / Q000494:pharmacology; D020134:Catalytic Domain; D002863:Chromogenic Compounds / Q000032:analysis; D003435:Crotalid Venoms / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000201:enzymology* / Q000494:pharmacology / Q000633:toxicity; D017839:Crotalus / Q000378:metabolism*; D005342:Fibrinolysis / Q000187:drug effects; D006470:Hemorrhage / Q000139:chemically induced; D006487:Hemostasis / Q000187:drug effects*; D006493:Heparin / Q000494:pharmacology; D006801:Humans; D008297:Male; D045726:Metalloproteases / Q000037:antagonists & inhibitors; D051379:Mice; D011480:Protease Inhibitors / Q000145:classification / Q000494:pharmacology*; D015842:Serine Proteinase Inhibitors / Q000494:pharmacology; D013045:Species Specificity; D014687:Venezuela
chemical_list: D000991:Antithrombins; D002863:Chromogenic Compounds; D003435:Crotalid Venoms; D011480:Protease Inhibitors; D015842:Serine Proteinase Inhibitors; D006493:Heparin; D045726:Metalloproteases