Which of the following statement is true about secondary bile acids?Rpt 2008 Q No54
High-Yield Explanation
Ans: c (Reabsorbed by enterohepatic circulation)Ref: Lippincott, 2nd edi., Pg. 223Bile acids are synthesized in the liver by multi-step pathway in which hydroxyl groups are inserted at specific location on the steriod structure. Bile acids are produced from cholesterol and rate limiting step is catalyzed by cholesterol 7 alpha hydroxylase.Primary bile acids are cholic and chenodeoxycholic acid.Primary bile acids are conjugated with taurine or glycine to form bile salts and not secondary bile acids.Bile salts include glycocholic acid, glycochenodeoxycholic acid, taurocholic acid and taurocheno deoxycholicacid.Bacteria will deconjugate bile salts to bile acids in the intestine and not in the liver. Both primary and secondary bile acids undergo enterohepatic circulation.Secondary bile acids are deoxycholic acid and lithocholic acid. So most probably the answer is "reabsorbed by enterohepatic circulation" as it is given that mixture of primary bile acids, secondary bile acids and bile salts undergo enterohepatic circulation primarily in the ileum.