It has been found out that obesity in Zucker rats and also ob/ob mice is associated with a high plasma aminopeptidase A (AP-A) activity, the enzyme responsible for generating angiotensin III, thus contributing to blood pressure control (Morais et al., 2017; Lory et al., 2019). This evidence concerns the gene ENPEP and obesity due to melanocortin 4 receptor deficiency.