Sensitivity of experimental venous and arterial thrombosis and bleeding to ancrod-induced defibrinogenation.

Abstract

The effect of ancrod-induced defibrinogenation on thrombosis and bleeding time was determined in anesthetized rats. Functional plasma fibrinogen levels were reduced 42, 71, 94 and 93% by ancrod doses of 5, 10, 20 and 30 U/kg, respectively, while a 2.5 U/kg dose was without significant effect. Ancrod inhibited vena cava thrombosis induced by partial stasis of blood flow combined with mild vascular injury. Thrombus weight was decreased 85 and 93% by the 10 and 20 U/kg doses, but was unaffected at lower doses. In contrast, ancrod doses of up to 30 U/kg did not significantly decrease carotid artery thrombi formed in response to oxidative transmural vessel injury. Ancrod caused a dose-dependent increase in bleeding time measured by puncturing small mesenteric arteries with a hypodermic needle. The bleeding time increase was approximately 38% in response to the 2.5 and 5 U/kg doses, and 182% in response to the 10 U/kg dose. These studies demonstrate that ancrod-induced reductions in plasma fibrinogen more effectively inhibit venous compared to arterial thrombosis, although these activities require doses that also increase bleeding time in small arteries.

• Authors: W A Schumacher, C L Heran, T E Steinbacher
• Journal: Thrombosis research (Thromb Res) Vol. 81 Issue 2 Pg. 187-94 (Jan 15 1996) ISSN: 0049-3848 [Print] United States
• PMID: 8822133 (Publication Type: Journal Article)

Chemical References

• Fibrinolytic Agents
• Fibrinogen
• Ancrod

Topics

• Ancrod (administration & dosage)
• Animals
• Blood Flow Velocity
• Carotid Arteries
• Fibrinogen (drug effects, metabolism)
• Fibrinolytic Agents (administration & dosage)
• Hemorrhage (blood, physiopathology)
• Male
• Rats
• Rats, Sprague-Dawley
• Thrombosis (blood, drug therapy, physiopathology)
• Vena Cava, Inferior