Activation of FXR in the ileum also induces the expression of fibroblast growth factor‐19/15 (human FGF‐19, mouse FGF‐15), a hormone that is secreted into the portal blood and transported to the liver to repress the expression of CYP7A1, a rate‐limiting enzyme for BA synthesis.4 Thus, hepatic FXR and intestinal FXR coordinate to ....