产品描述:
Cholic acid-24-13C is intended for use as an internal standard for the quantification of cholic acid (Item No. 20250) by GC- or LC-MS. Cholic acid-24-13C is an isotopically labeled form of cholic acid containing 13C at the carbon-24 position. Cholic acid is a primary bile acid.{52692} It is formed from cholesterol via a multistep process catalyzed by the cytochrome P450 (CYP) isoforms CYP7A1, CYP8B1, and CYP27A1. Cholic acid is conjugated to glycine or taurine by bile acid-CoA:amino acid N-acyltransferase (BAAT) to produce glycocholic acid (GCA; Item No. 20276) and taurocholic acid (TCA; Item No. 16215), respectively, in the liver, and is transformed into the secondary bile acid deoxycholic acid (DCA; Item No. 20756) by intestinal microbiota.{52692,61155,61156} It induces C. difficile colony formation in an agar dilution assay when used at a concentration of 0.1% w/v.{61157} Dietary administration of cholic acid (0.4% w/w) increases serum cholesterol levels, biliary phospholipid secretion, and fecal DCA levels in rats.{61158}