Furthermore, peri-hippocampal injection of AβpE3-42 into APPswe/NOS2-/- AD mice led to the presence of both AβpE3-42 and conventional Aβ plaques, which the authors mention was hardly seen in sham injected AD mice or WT mice injected with AβpE3-42 [25]. This evidence concerns the gene NOS2 and Alzheimer disease.