P2RX7 and Alzheimer disease: The P2RX7 receptor is thought to have a central role in the progression of AD disease based on the increased expression of P2RX7 in the proximity of amyloid-β (Aβ) in the amyloid plaques of AD patients and in animal models of AD (Parvathenani et al., 2003; McLarnon et al., 2006).