Chapter 9 Mechanism of bile acid biosynthesis in mammalian liver

摘要: Publisher Summary This chapter discusses the mechanism of bile-acid biosynthesis in mammalian liver. Generally, most important pathway for metabolism and excretion cholesterol mammals is formation bile acids. The major primary acids, cholic chenodeoxycholic acid, are formed from liver secreted with to intestine. reactions involved saturation double bond, epimerization 3β-hydroxyl group, introduction hydroxyl groups into 7α 12α positions, oxidation C27, side chain a C24-carboxylic conjugation taurine or glycine. sequence these has been studied extensively pathways have defined high degree certainty rat man. After secretion acids intestine, microorganisms may transform them secondary such as deoxycholic lithocholic acid. part all intestine absorbed returns via portal blood. Only small fraction excreted feces. returning enterohepatic circulation be further metabolized before they reconjugated re-excreted bile. conversion represents obvious example capacity convert lipid-soluble material excretable water-soluble products.