This enzyme is now most commonly referred to as the insulin-regulated aminopeptidase (IRAP, EC 3.4.11.3), although it is also known as oxytocinase and placental leucine aminopeptidase in reproductive and endocrine contexts.12,13 In healthy rat brains, IRAP is highly expressed in regions central to memory and learning such as the hippocampus and the neocortex.8,14,15 Since IRAP inhibition has been linked to cognitive enhancement, it is a promising molecular target in the context of AD.16,17. This evidence concerns the gene LNPEP and Alzheimer disease.