P2RY12 and brain injury: Further, immunofluorescence imaging of P2Y12-positive microglia in the cortex of sham and mice subjected to traumatic brain injury (TBI) has shown that P2Y12-positive microglia was converted into activated microglia following the release of the inflammatory cytokines IL-1β, TNF-α, CCL2, IL-6, at 24 h post-injury [100].