INS and Hepatic steatosis: After a 10-week HFD treatment, HET D2R (+/-) mice exhibited significantly higher values for hepatic steatosis (p<0.001), areas under the curves (AUCs) for the glucose tolerance test (GTT) and the insulin tolerance test (ITT) (p<0.001 & p<0.001 respectively), serum leptin (p=0.005) and total cholesterol (TC ) (p=0.009), in conjunction with decreased locomotor activity (p=0.031), compared to HET mice exposed to standard chow.