Plasminogen-streptokinase, acylated

Fig. 4. Fibrinolytic system where SCUPA is single-chain urokinase plasminogen activator rTPA is recombinant tissue plasminogen activator APSAC is acylated plasminogen streptokinase activator complex SK is streptokinase and UK is urokinase.

APSAC = acylated plasminogen streptokinase activator complex. 

Acyclo-retinoic acid, 17 662 Acylaminoanthraquinone dyes, 9 333, 334 Acylated plasminogen-streptokinase activator complex, 5 175, 177-178 Acylates, titanium, 25 96 Acylating agents, 12 174 Acylation, 9 282 12 173-188... 

Anistreplase (anisoylated plasminogen streptokinase activator complex APSAC) consists of a complex of purified human plasminogen and bacterial streptokinase that has been acylated to protect the enzyme s active site. When administered, the acyl group spontaneously hydrolyzes, freeing the activated streptokinase-proactivator complex. This product (recently discontinued in the USA) allows for rapid intravenous injection, greater clot selectivity (ie, more activity on plasminogen associated with clots than on free plasminogen in the blood), and more thrombolytic activity. 

Streptokinase and plasminogen form a complex having the characteristics of a plasminogen activator and activating plasminogen molecules not yet combined with streptokinase to plasmin. The concept of acylation of fibrinolytic enzymes... 

Anisoylatedplasminogen streptokinase activator complex (APSAC)(Table 11-4) is an anisoyl (p-methoxybenzoyl) derivative of the active (lysine) site of the plasminogen component of this complex. Acylation inactivates the enzyme but does not decrease the affinity of the complex for fibrin. The resultant slow deacylation (tU2 = 40 min) should achieve relative selectivity for the fibrin in the clot over circulating plasma fibrinogen. Hydrolysis of anisoyl amide following binding onto the thrombus (i.e., activation) leads to fibrinolysis. APSAC has been reported to produce a 60-80% reperfusion rate following IV administration. 

Unfortunately, the half-life of the activator complex is less than 30 minutes, which frequently is too short to completely lyse a thrombus. Anistreplase (APSAC Eminase) is a 1 1 streptokinase/lysine-plasminogen complex that has been acylated with an anisoyl group at the active-site serine within... 

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