Inhibition of thromboplastic activity by Trasylol. In vitro investigations concerning the mechanism of inhibition.

In vitro experiments with the thromboplastin activation test (TAT) indicate that Trasylol primarily is an inhibitor of the contact phase of intrinsic clotting. However, also later stages seem to be inhibited to a certain extent. The activating effect of serum and brain thromboplastin on the thromboplastin activation was prevented or reduced by Trasylol but the activating effect of minimal amounts of thrombin was only slightly reduced. The possible significance of the findings in vivo are briefly discussed.