FXR deficiency in Ldlr−/− mice resulted in increased expression of genes involved in energy metabolism in BAT and skeletal muscle. A and B, The mRNA levels of genes in BAT (A) or skeletal muscle (B) were determined by qRT-PCR (n = 8 per group). C, FXR mRNA levels were determined by qRT-PCR in wild-type mice (n = 5 per group). D, cAMP levels were determined (n = 8 per group). Ido2, Type 2 iodothyronine deiodinase. *, P < 0.05.