Labelled Chenodiol (Chenodeoxycholic acid). A major bile acid in many vertebrates, occurring as the N-glycine and/or N-taurine conjugate. With other bile acids, forms mixed micelles with lecithin in bile which solubilize cholesterol and thus facilitates its excretion. Fcilitates fat absorption in the small intestine by micellar solubilization of fatty acids and monoglycerides. Anticholelithogenic. Epimeric with Ursodiol.