Thromb Haemost 1996; 75(05): 816-819
DOI: 10.1055/s-0038-1650372
Original Article
Schattauer GmbH Stuttgart

Comparative Effects of Staphylokinase and Alteplase in Rabbit Bleeding Time Models

Steven Vanderschueren
The Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
,
Désiré Collen
The Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
› Author Affiliations
Further Information

Publication History

Received 08 December 1995

Accepted after revision 29 January 1996

Publication Date:
26 July 2018 (online)

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Summary

Background: The pathogenesis of bleeding associated with thrombolytic therapy remains largely unknown, although spontaneous bleeding appears to correlate with bleeding time prolongation. Here, the comparative effects on cuticle bleeding times (CBT) and ear puncture bleeding times (EBT) of recombinant staphylokinase (Sak) and alteplase (recombinant tissue-type plasminogen activator, rt-PA) at equivalent doses, alone and in combination with aspirin and heparin, were studied in rabbits.

Methods and Results: Groups of 4 to 9 rabbits were allocated to one of the 8 following intravenous infusions: saline; aspirin 15 mg/kg and heparin - 100 IU/kg bolus and 10 IU/kg infusion over one hour; 1.5 mg/kg rt-PA; 1.5 mg/kg rt-PA plus aspirin and heparin; 4.5 mg/kg rt-PA; 0.5 mg/kg Sak; 0.5 mg/kg Sak plus aspirin and heparin and 1.5 mg/kg Sak. Bleeding times were determined 30 and 15 min before and 5,15,30 and 60 min after the administration over one min of saline, rt-PA or Sak, by simultaneously severing a nail cuticle (CBT) and by puncturing the ear (EBT). Bleeding times were unaffected by saline and by both doses of Sak in monotherapy. Heparin-aspirin and low dose rt-PA significantly lengthened EBT but not CBT. Both CBT and EBT were significantly prolonged (to a mean of >4 times pretreatment at 5 min) after high-dose rt-PA and after the combined administration of heparin and aspirin with either Sak or rt-PA. rt-PA provoked significantly longer bleeding than Sak in the CBT (p = 0.001; mean estimated difference = 23 min), but not in the EBT. rt-PA but not Sak degraded plasma fibrinogen dose-dependently. CBT correlated inversely with fibrinogen (r = −0.66, p = 0.001) but EBT did not.

Conclusions: At equivalent doses Sak displays a significantly higher fibrin specificity and prolongs bleeding time less than rt-PA, particularly in the nail cuticle bleeding time model in which larger vessels are injured that require fibrinogen for hemostasis.