CNR1 and obesity due to melanocortin 4 receptor deficiency: Accordingly, Cota et al. showed, in a mouse model of high fat diet (HFD)-induced obesity, that the hepatic expression of CB1R was significantly increased in wild-type mice fed an HFD compared with those fed a normal diet, suggesting that the increase level of CB1R observed in NAFLD is due to fat-metabolism disorders [55].