Time course of thrombotic changes after microsurgical carotid endarterectomy in the rat.

An experimental model of microsurgical carotid endarterectomy in rats developed recently in our laboratory was used in the present study. Our adult Sprague-Dawley rats were killed by in vivo perfusion-fixation at 5 minutes, 15 minutes, 30 minutes, 3 hours, 1 day, and 3 days after the completion of carotid endarterectomy, and vessels were studied by scanning electron microscopy, light microscopy, and transmission electron microscopy for evaluation of thrombotic changes at the level of arterial injury. Although no postoperative carotid occlusion was observed, thrombus formation was noted as early as 15 minutes after recirculation. Thrombus formation reached its peak at 3 hours and was no longer detected 3 days after the procedure. Microsurgical carotid endarterectomy in rats may be a useful experimental model for the evaluation of antithrombotic drugs.