Whereas it has been reported that obesity and insulin resistance are related with low plasma adiponectin concentrations in this animal model, and that restoration of plasma adiponectin levels are associated with a decrease in body weight gain and reduced hyperinsulinema and dyslipidemia [20, 21, 28], Vendrame et al. and Oana et al. [28, 29] also observed that obese Zucker rats of 13–17 weeks of age presented higher adiponectin levels than their lean counterparts. This evidence concerns the gene ADIPOQ and obesity due to melanocortin 4 receptor deficiency.