a, Micro-osmotic pump connected to a cannula through a plastic catheter. b, The micro-osmotic pump was implanted in a subcutaneous pocket and the cannula stereotaxically positioned to deliver the ASO into the right ventricle. c, Section schemata from the Paxinos and Franklin35 mouse brain atlas showing site of cannula implantation. d, Injection of 1 µl of dye through the catheter to show that the dye reaches the whole ventricular system, confirming the correct positioning of the tip of the cannula in the right ventricle. e, RT–qPCR for Aif1 (a marker of activated microglia) and Gfap (a marker of astrocytes) immediately after the end of 4 weeks of gradual ASO treatment (n = 4 for wild-type group; n = 5 for transgenic group; n = 4 for TG-ASO group). Data are mean ± s.e.m.