Consistent with this point of view, we further found that knockdown of RIP1K or Nec-1 delayed treatment could promote the neuronal axonal generation in glial scar in a neuron and astrocyte co-culture system in vitro and reduced the necrotic cells in lesion region of cerebral cortex and the volume of brain atrophy at late stage of 28 days after I/R injury. This evidence concerns the gene PCSK1 and Atrophy.