FAAH deficiency promotes energy storage and enhances the motivation for food.

Rationale: Fatty acid amide hydrolase (FAAH) is the main degrading enzyme of the fatty acid ethanolamides anandamide (AEA) and oleoylethanolamide (OEA), which have opposite effects on food intake and energy balance. AEA, an endogenous ligand of CB(1) cannabinoid receptors, enhances food intake and energy storage, whereas OEA binds to peroxisome proliferator-activated receptors-alpha to reduce food intake and promoting lipolysis. To elucidate the role of FAAH in food intake and energy balance, we have evaluated different metabolic and behavioral responses related to feeding in FAAH-deficient (FAAH(-/-)) mice and their wild-type littermates.