Microthrombosis after experimental subarachnoid hemorrhage: Time course and effect of red blood cell-bound thrombin-activated pro-urokinase and clazosentan

► Thrombosis is proposed as a novel mechanism of delayed cerebral ischemia after SAH. ► Microclots form after experimental subarachnoid hemorrhage in mice. ► Modified urokinase bound to RBCs safely and effectively reduces microclot burden. ► Clazosentan is associated with an increase in microclot burden. ► Microclot formation may represent a new target for therapeutic intervention.