Effects of Alteplase, a Thrombolytic Agent, in a Rat Photothrombotic Middle Cerebral Artery Occlusion Model

In this study, we examined the effects of alteplase, a recombinant tissue-type plasminogen activator (t-PA), in a simple and reproducible rat middle cerebral artery (MCA) occlusion model induced by photoillumination with 12 mg/kg of rose bengal. A clinically equivalent dose of alteplase (3 mg/kg), which was administered just after thrombotic occlusion of the MCA, significantly reopened the thrombotic MCA occlusion in 16 of 23 animals (69.6%) when compared with vehicle-treated animals (8 of 22 animals, 36.4%). In addition, alteplase significantly reduced cerebral damage and improved neurological deficits. Although it has been reported that t-PA possesses neurotoxicity, the present findings suggest that alteplase was effective in a rat acute stroke model due to reopening of thrombotic MCA occlusion. This new model is very useful for investigating the efficacy of thrombolytic agents in stroke research, providing a condition similar to the clinical setting.