Establishment and evaluation of middle cerebral artery occlusion (MCAO) models in SD rats

ObjectiveTo establish the model of focal cerebral ischemia with favorable reproducibility and stability, and investigate the syndrome of neurological severity, the volume of cerebral infarction and the pathological changes after different ischemic time.MethodsTo establish cerebral ischemia model,the low-setting skull window was performed, and the middle cerebral artery (MCA) was obstructed by thermocoagulation with less area of injury. These models were divided randomly into four group according to the different ischemic time(3d,7d,14d and 21d). Neurological severity score (NSS), triphenyltetrazolium chloride (TTC) staining and HE staining were adopted to observe dynamically the syndrome of neurological severity, the volume of cerebral infarction and the pathological changes. ResultsThe neurological severity(2.78±0.44 ~ 1.67±0.50), cerebral infarction(197.05±23.38 ~ 135.15±13.18) and pathological changes appeared distinctly in all rats after operation. The syndrome of neurological severity ameliorated and the volume of cerebral infarction deflated significantly comparing 3d group with 7d group after ischemia (P0.01), and the diversity went stable after 7 days (P0.05). ConclusionThe method is simple and convenient, and the MCAO model has favorable reproducibility and stability.