Activators such as the tissue plasminogen activator tPA and the urokinase-type plasminogen activator uPA intervene in the process of converting plasminogen into plasmin but are offset by activation inhibitors such as the plasminogen activation inhibitor PAI-1, α1 inhibitor of plasmin and the more recently described thrombin-activated fibrinolysis inhibitor TAFI.
Estos son contrarrestados por inhibidores de la activación como el inhibidor del activador del plasminógeno PAI-1, el inhibidor α1 de la plasmina y el más recientemente descrito, inhibidor de la fibrinólisis activado por trombina TAFI.