Table 2

Activated partial thromboplastin time after injection of hirudin

aPTT (s)
25 min *2 h, 20 min *6 h, 20 min *
PBS68.5 ± 3.278.3 ± 7.872.0 ± 12.7
Hirudin>300>100 (100, 189, >300, >300) 54.9 ± 3.0
  • Abbreviation: aPTT, activated partial thromboplastin time.

  • * Mice (nu/nu) received 10 mg/kg hirudin intravenously. At the indicated times, mice were sacrificed, and blood was obtained from the vena cava for determination of the aPTT.

  • At 2 hours, all mice were anticoagulated, but the extent, as indicated by the aPTT, was highly variable. By 6 hours, the effect of hirudin injection was no longer evident.