Table 1. Functions and Sites of Action of Bile Acids.

Summary of known functions and sites of action of bile acids present in the rodent and human bile acid pool.

Function	Site of Action
Micelles prevent cholesterol crystallization	Gall bladder and bile duct
Micelles facilitate lipid digestion by pancreatic enzymes	Intestinal lumen
Micelles facilitate vitamin A, D, E and K absorption	Intestinal lumen
Impair bacterial over-growth	Intestinal lumen
Maintain intestinal barrier to infection	Intestine
FXR activation: CDCA>DCA>LCA≫CA	Liver, Ileum, kidney, adrenal gland
TGR5 activation: LCA>DCA>CDCA>CA (Taurine conjugation reduces EC50)	Gall bladder, intestinal neuroendocrine cells, enteric neurons, brown adipose tissue, macrophages, brain
PXR activation: LCA~3-keto-LCA	Intestine, liver
VDR activation: LCA~3-keto-LCA	Ileal enterocytes