The present invention provides an electrode designed for implantation into the central nervous system (CNS) of a mammal, wherein said electrode is substantially coated with interleukin-1 receptor antagonist (IL-1ra) or a coating composition comprising it, and the IL-1ra actively inhibits scarring on or around the surface of the electrode when implanted into the CNS. The electrode of the invention may be used for brain recording and/or stimulation, and can thus be used for treatment of a brain dysfunction, a brain disease or disorder, or a brain injury, as well as for brain computer interface, brain machine interface, or electrotherapy.
