Since the mild and delayed-onset hyperglycemia in KKAy mice (Srinivasan and Ramarao, 2007) might mask the effects of PACAP in this model, we recently re-examined the phenotypic effects of PACAP overexpression in KKAy mice fed a high-fat diet (HFD) (Sakurai et al., 2012). This evidence concerns the gene ADCYAP1 and Hyperglycemia.