ATP-ase as an in_vitro Inhibitor of Surface Factor in the Blood-Clotting Mechanism. ∗

Abstract

Summary

As little as 5 μg/ml ATP-ase, at pH 7.0, shows a significant inhibitory effect on surface factor (SF or activation product) in vitro. ATP-ase does not inhibit thrombin, tissue thromboplastin, thrombokinase, trypsin, stypven, factors IX, VIII, × or V. The specific anti-SF effect of ATP-ase cannot be related to ATP or ADP. It may be significant in vivo, since platelets are a source of ATP-ase (thrombosthenine), and active SF is present in the platelet plasmatic atmosphere.