Effect of aspirin on the fibrinolytic response in perfused rat hindquarters

The role of aspirin in tissue plasminogen activator (t-PA) release was studied in rats after experimental venous occlusion. For this purpose, we developed a new experimental model which combines a vascular perfusion system (isolated rat hindquarters) with vascular stimulation, namely the application of venous stasis. Application of venous stasis for 30 min induced the release of t-PA from the vascular endothelium into the perfusate (from 0.19 ± 0.05 to 0.39 ± 0.05 UI/ml), reaching a peak 90 s after reperfusion. Aspirin administered to rats 60 min before the experiments (100 mg/kg i.v.), or dissolved in Tyrode solution (100 μM), suppressed 6-keto-prostaglandin F 1α (6-keto-PGF 1α) synthesis (0.38 ± 0.09 in control and