P2RX7 and Alzheimer disease: Interestingly, inhibition of P2X7 in mice, transgenic for mutant human amyloid precursor protein, reduced the number of amyloid plaques in the hippocampus [140] and stimulation of P2X7 receptors on human macrophages and microglia enhanced the degenerative lesions observed in AD [141] (Tables 3 and 4).