Fibrin(ogen)olytic character of FIIa isolated from Agkistrodon acutus venom.
OBJECTIVE
To investigate the fibrin(ogen)olytic character of FIIa isolated from Agkistrodon acutus venom in vitro and in vivo.


METHODS
125I-labeled human plasma clot lysis was measured in vitro and rabbit carotid artery thrombosis was as an in vivo model.


RESULTS
In vitro, urokinase (UK) at 25, 35, 40, 45, 60 kU/L and FIIa at 0.08, 0.23, 0.4, 0.5, and 0.7 g/L resulted an equivalent clot lysis (20%, 40%, 50%, 60%, and 80%). UK at 25 to approximately 60 kU/L induced 27.3%+/-3.6%, 35.2%+/-2.3%, 39.3%+/-2.4%, 44.2%+/-4.6%, and 51.1%+/-1.2% fibrinogen degradation. But FIIa at 0.08 approximately -0.7 g/L induced 95.4%+/-0.3%, >95.6%, >95.6%, >95.6%, >95.6% fibrinogen degradation respectively. In vivo, UK 40 kU/kg and FIIa 1.0 mg/kg reduced the weight of residual thrombus to 9.0+/-2.5 mg and 7.8+/-3.5 mg compared with negative control group (30.0+/-5.4 mg). But the fibrinogen degradation rate after UK 40 kU/kg and FIIa 1.0 mg/kg treatment was 24.4%+/-6.2% and 4.1%+/-7.8%, respectively (P<0.05, n=6). The order of the lysis speed after UK 125 kU/L treatment was platelet poor plasma (PPP) clots>the whole blood clots>platelet rich plasma (PRP) clots. The sequence for FIIa 0.4 g/L was PRP >PPP >whole blood clots.


CONCLUSIONS
At the same percentage of clot lysis, FIIa degraded more fibrinogen than UK did in vitro but less fibrinogen than UK did in vivo. The order of the lysis speed was PPP>whole blood clots>PRP clots for UK and PRP>PPP>whole blood clots for FIIa.
Wang
Yi-wen
YW
Department of Pharmacology, Zhongshan Medical College, Sun Yat-sen University, Guangzhou 510080, China.
Liang
Xiu-xia
XX
Chen
Jia-shu
JS
Chen
Qi
Q
Qiu
Peng-xin
PX
Lin
Xi
X
Yan
Guang-mei
GM
D017836:Agkistrodon; D000818:Animals; D002341:Carotid Artery Thrombosis / Q000503:physiopathology*; D003435:Crotalid Venoms / Q000008:administration & dosage / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005342:Fibrinolysis / Q000187:drug effects*; D005343:Fibrinolytic Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology; D008297:Male; D008666:Metalloendopeptidases; D011817:Rabbits; D014568:Urokinase-Type Plasminogen Activator / Q000494:pharmacology
D003435:Crotalid Venoms; D005343:Fibrinolytic Agents; D014568:Urokinase-Type Plasminogen Activator; C478420:FIIa; D008666:Metalloendopeptidases