In vivo, nicotine prevents microglial activation or proliferation after LPS injection in substantia nigra [42] and global ischemia in rats [43], and activation of α7 nAChR reduced M1/M2 ratio of macrophages in the peri-infarct of animals subjected to ischemic stroke and bone fracture [44]. The gene discussed is CHRNA7; the disease is ischemic stroke.