Afibrinogenemia and Thrombocytopenia in Guinea Pigs Following Injection of Echis Colorata Venom

Abstract

Intravenous injection into the guinea pig of lethal doses of Echis colorata venom or of each of its two chromatographic fractions, separately, caused hemorrhage, afibrinogenemia, factor V deficiency and thrombocytopenia. Sublethal venom doses caused afibrinogenemia, factor V deficiency and thrombocytopenia in the absence of hemorrhage. Early intravascular clotting was observed following injection of high lethal doses of both whole venom and of procoagulant-containing fraction II, but not of fraction I which was devoid of procoagulant activity. The afibrinogenemia produced by fraction I was due to its fibrinogenolysin, whereas the afibrinogenemia produced by fraction II, which also had fibrinogenolytic activity, was due chiefly to its procoagulant. Anti-Echis colorata venom rabbit serum inhibited the fibrinogenolytic, the procoagulant and the thrombocytopenic activities of the venom.