Serum Thrombotic Accelerator (STA) Activity: Its Relation to the First Phase of Clotting.

Abstract

SummarySerum thrombotic accelerator (STA) activity requires for its elaboration activation of HF, PTA, and Factor IX, but does not depend on platelets or any other recognized coagulation factor with the possible exception of Ca++. Although essential in the donor serum for formatioln of this thrombotic moiety, HF, PTA, and Factor IX need not be present in the recipient animal for thrombus formation to occur. STA activity is distinct from Ca++, HE, and PTA, and may not be identical with Factor IX; however, activatioln of HF appears to be the initial reaction required in the elaboration of this potent thrombotic agent that is distinct from thrombin and tissue thromboplastin.