Natural inhibitors of fibrinolysis

There are two main types of inhibitors of fibrinolysis: those which inhibit plasmin (plasmin inhibitors or antiplasmins) and those which inhibit the activation of plasminogen (anti-activators). Many substances derived from biological fluids, tissues, plants, or micro-organisms inhibit fibrinolysis. Some active site titrants of serine proteases are potent inhibitors of fibrnolytic enzymes and certain amino-acids such as lysine, 6-aminohexanoic acid, or tranexamic acid inhibit the digestion of fibrin. This review will deal mainly with the natural inhibitors of fibrinolysis occurring in human blood. The properties of the other inhibitors are reviewed elsewhere.' Inhibitors of plasmin occurring in human blood Human plasma exerts a very important inhibitory