AM 251 and β-Funaltrexamine reduce fat intake in a fat-preferring strain of mouse

This experiment aimed to examine the role of the CB1 and Opioid mu receptors on fat preference by administering the CB1 inverse agonist AM 251 (5 mg/kg i.p.) and the opioid mu antagonist β-Funaltrexamine (15 mg/kg s.c.) for 4 days to fat-preferring C57BL/6 mice fed a two-choice high-fat/low-fat diet. Both drugs were found to significantly reduce total energy intake, high-fat diet intake and fat preference during treatment.