Intracerebroventricular Injection

SOCS1-siRNA, SOCS3-siRNA, Axl-siRNA, SOCS1 and SOCS3-siRNA and Scramble-siRNA (Ambion Thermo Fisher Scientific, Waltham, MA) were injected 48 hours before MCAO by intraventricular injection (ICV) as previously described (Liu et al., 2014). The stereotactic ICV injection site was relative to bregma: anteroposterior 1 mm, right lateral 1.5 mm, depth 3.5 mm. A scalp incision was made along the midline, and a 1mm burr hole was drilled into the skull. 100 pmol/5μl siRNA was delivered into the ipsilateral ventricle with a Hamilton syringe (Microliter 701, Hamilton Company, Reno, NV) and administered over 5 minutes. The needle was left in place for an additional 5 minutes after injection to prevent possible leakage and was then slowly withdrawn over 4 minutes. After the needle was removed, the burr hole was sealed with bone wax. The incision was closed with sutures and the rat was allowed to recover.