A reproducible mice model of focal cerebral ischemia/reperfusion animal

Objective To introduce a reproducible mice model of focal cerebral ischemia/ reperfusion animal, and observe the changes of cerebral volume of infarction and edema at different time-point of ischemia/reperfusion following MCAO. Methods Focal cerebral ischemia/reperfusion was induced by occlusion of the middle cerebral artery(MCA) using the intraluminal filament technique. The whole mice brain was stained with TTC, and the slices of brain tissue stained with cresyl-violet. The cerebral blood flow was monitored with laser-Doppler flow metry. The cerebral volume of infarction and edema was quantified with ImageJ software. Results The cerebral blood flow dropped sharply after MCAO, and jumped rapidly after reperfusion. After cerebral ischemia, the infarct area was very clear, and the volume of infarction and edema remained stable. In the group of ischemia 90 min/reperfusion 24 h, the volumes of infarction and edema and neurological deficit score were significantly larger than those in the group of 30 min ischemia / 24 h reperfusion (P0.001). After 30 min cerebral ischemia /24 h reperfusion and 72 h reperfusion, edema appeared remarkablely (61.6±3.5) mm3, (72.6±4.3) mm3 respectively (P0.001), whereas the volume of edema descended to only (50.9±4.1) mm3 after 7 d reperfusion. However, after reperfusion 30 d, the volume of whole brain shrank, and the volume of edema came to negative value (-20.1±1.8) mm3. Conclusion This cerebral ischemia/ reperfusion mice model is reproducible and easy to operate. Cerebral ischemia 30 min will induce irreversible brain damage. The edema will come to peak after reperfusion 72 h.