The in vitro analysis of the coagulation mechanism of activated factor VII using thrombelastogram.
We investigated the effects of addition of recombinant activated coagulation factor VII (rFVIIa) to coagulation factor-deficient plasma and whole blood, using thrombelastograms (TEGs). The addition of rFVIIa to factor II- or X-deficient plasma did not correct hemostatic parameters, whereas it produced partial responses in factor V-, VIII- or IX-deficient plasma and good responses in factor VII-, XI- or XII-deficient plasma. Furthermore, the addition of rFVIIa and platelets (30-100 x 10(3)/ micro l) to platelet-poor plasma produced marked corrections, producing TEGs similar to those of platelet-rich plasma. These results indicate that factors II and X are essential for the hemostatic effects of rFVIIa, and that factors V and VIII promote these effects. We believe that TEGs are, at present, one of the most useful tools for evaluating in vitro hemostatic effects of rFVIIa.
Kawaguchi
Chiharu
C
Division of Neonatal Intensive Care, Nara Medical University Hospital, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan.
Takahashi
Yukihiro
Y
Hanesaka
Yae
Y
Yoshioka
Akira
A
D000328:Adult; D001777:Blood Coagulation; D002118:Calcium / Q000494:pharmacology; D005165:Factor V / Q000502:physiology; D005167:Factor VII / Q000494:pharmacology*; D005169:Factor VIII / Q000502:physiology; D015942:Factor VIIa; D005170:Factor X / Q000502:physiology; D006467:Hemophilia A / Q000097:blood; D006801:Humans; D010976:Platelet Count; D011516:Prothrombin / Q000502:physiology; D011994:Recombinant Proteins / Q000494:pharmacology*; D013916:Thrombelastography
D011994:Recombinant Proteins; D005165:Factor V; D005167:Factor VII; D011516:Prothrombin; D005169:Factor VIII; D005170:Factor X; C103587:recombinant FVIIa; D015942:Factor VIIa; D002118:Calcium