P2RX7 and Alzheimer disease: Deregulation of P2X7 receptor has previously been indicated to be common for diverse situations of brain damage, such as ischemia [61, 62], traumatic brain injury [63], spinal cord injury [64], epilepsy [65], Alzheimer’s disease [59, 66], Parkinson’s disease [67], prion disease [68], or Huntington’s disease [69].