A novel embolic middle cerebral artery occlusion model induced by thrombus formed in common carotid artery in rat

Stroke is a major cause of death and disability worldwide. However, treatment options to date are very limited. To meet the need for validating the novel therapeutic approaches and understanding the physiopathology of the ischemic brain injury, experimental stroke models were critical for preclinical research. However, commonly used embolic stroke models are reluctant to mimic the clinical situation and not suitable for thrombolytic timing studies. In this paper, we established a standard method for producing a rat embolic stroke model with autologous thrombus formed within the common carotid artery (CCA) by constant galvanic stimulation. Then the thrombus was shattered and channeled into the origin of the MCA and small (lacunar) artery. To identify the success of MCA occlusion, regional cerebral blood flow was monitored, neurological deficits and infarct volumes were measured at 2, 4 and 6h postischemia. This model developed a predictable infarct volume (38.37 ± 2.88%) and gradually reduced blood flow (20% of preischemic baselines) within the middle cerebral artery (MCA) territory. The thrombus occluded in the MCA was able to be lysed by a tissue-type plasminogen activator (t-PA) within 4h postischemia. The techniques presented in this paper would help investigators to overcome technical problems for stroke research.