Novel rat middle cerebral artery occlusion model: Trans-femoral artery approach combined with preservation of the external carotid artery.

We developed a novel trans-femoral artery approach to the rat middle cerebral artery occlusion model (TF-MCAO) without sacrificing the external carotid artery (ECA) with/without the pterygopalatine artery, which is important for chewing food. To make the TF-MCAO we first dissect the left common carotid artery (CCA), ECA, and internal carotid artery (ICA). Transient occlusion clips are applied to the proximal ECA and the pterygopalatine artery; we never sacrifice the ECA branch. A 24-gage catheter is inserted into the left femoral artery. We insert a slightly bent 0.014in. hydrophilically coated guide wire via a haemostasis valve. Anatomically, the left common carotid artery is located rostral to the descending aorta, permitting a straight-forward, blind approach to the CCA. The guide wire is gently advanced about 17mm from the bifurcation of the CCA until slight resistance is encountered. The guide wire and temporary occlusion clips are withdrawn after 90min. Rats were sacrificed 24h after reperfusion. Eleven rats were examined. One rat died before occlusion due to deep anesthesia. The success rate for producing infarction was 80%. The mean infarction volume of the basal ganglia was 94.4mm(3)+/-9.4 se and mean infarction volume of the cerebral cortex was 124.2mm(3)+/-21.6 se. No rat died due to cerebral infarction and no rat suffered subarachnoid hemorrhage. We conclude that TF-MCAO was useful for producing a cerebral infarction.