APP and Alzheimer disease: In mouse models of AD, overexpression of amyloid precursor protein (APP) can drive Aβ deposits, and these deposits have been associated with cerebrovascular dysregulation (Zhang et al., 1997; Koistinaho et al., 2002), decreased NVC (Niwa et al., 2000b) and increased microvessel response to vasoconstrictor molecules, potentially biasing the vasculature toward constriction over dilation (Niwa et al., 2001).