The cardiovascular and haematological effects of purified prothrombin activator from the common brown snake (Pseudonaja textilis) and their antagonism with heparin.
The cardiovascular and haematological effects of purified prothrombin activator derived from the venom of the Australian Common Brown Snake (Pseudonaja textilis) were studied in anaesthetised, mechanically ventilated dogs. Severe depression of systemic blood pressure and cardiac output and a rise in central venous pressure were observed. Thrombocytopenia, prolongation of both prothrombin time and activated partial thromboplastin time and a reduction in serum fibrinogen were also observed. All of these observed effects were prevented by the prior administration of heparin--a naturally occurring anticoagulant. We conclude that the prothrombin activator in Pseudonaja textilis venom may cause cardiovascular depression due to myocardial dysfunction secondary to disseminated intravascular coagulation.
Tibballs
J
J
Animal Research Laboratory, Royal Children's Hospital, Melbourne, Victoria, Australia.
Sutherland
S K
SK
Rivera
R A
RA
Masci
P P
PP
D000818:Animals; D001777:Blood Coagulation / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D002496:Central Venous Pressure / Q000187:drug effects; D004285:Dogs; D004546:Elapid Venoms / Q000032:analysis* / Q000302:isolation & purification / Q000494:pharmacology*; D004562:Electrocardiography / Q000187:drug effects; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis; D005340:Fibrinogen / Q000032:analysis; D005343:Fibrinolytic Agents / Q000302:isolation & purification / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects*; D006327:Heart Block / Q000139:chemically induced; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D006493:Heparin / Q000494:pharmacology*; D013318:Stroke Volume / Q000187:drug effects; D013610:Tachycardia / Q000139:chemically induced; D013921:Thrombocytopenia / Q000139:chemically induced
D004546:Elapid Venoms; D005338:Fibrin Fibrinogen Degradation Products; D005343:Fibrinolytic Agents; C037525:textilotoxin; D005340:Fibrinogen; D006493:Heparin