抄録
The authors have previously reported that the determination method for antiplasmin using chromogenic substrate S-2251 was mainly sensitive to α2PI (α2 Plasmin Inhibitor). In this paper, differences in quantity of α2PI determined as amidase activity and immunoactivity was investigated in enhanced fibrinolytic state.
Plasma specimen were obtained from enhanced fibrinolytic cases composed of 6 DIC syndrome and 4 healthy and 2 phlebothrombotic disease receiving a single injection of Defibrase. It was found that the samples collected at 4-24 hours after Defibrase injection showed relatively high values of α2PI activity by SRID method as compared to S-2251 method. This discrepancy was caused by the appearance of α2PI·plasmin complex, which was confirmed by the cross immunoelectrophoretic pattern of each fraction obtained by gel chromatography (Sephadex G-150) of the plasma from phlebothrombotic disease receiving Defibrase. It was concluded that the S-2251 method determines only free α2PI, whereas the SRID method determines both free α2PI and the α2PI·plasmin complex. On injection of Defibrase, a strong fibrinolytic state will take place, with FDP reaching 1, 000-2, 000μg/ml in 4-8 hours, and the α2PI·plasmin complex appears in the plasma. But this complex will disappear within 24-48 hours after Defibrase injection. The rapid metabolism of this complex can be deduced by the fact that no α2PI ·plasmin complex was detected in DIC cases with high FDP level reaching 80-320μg/ml.
