Glycodeoxycholic acid-d₄is intended for use as an internal standard for the quantification of glycodeoxycholic acid by GC- or LC-MS. Glycodeoxycholic acid (GDCA) is a glycine-conjugated form of the secondary bile acid deoxycholic acid .¹It induces a reversible, concentration-dependent reduction in myogenic tone in rats and decreases expression of the gene encoding the cytochrome P450 (CYP) isoform 7A1 (CYP7A1) in rabbits.^2,3Serum levels of GDCA are elevated in non-surviving patients with acetaminophen-induced acute liver failure (AALF) compared with survivors.⁴GDCA levels are also increased in the plasma of patients with asthma.⁵

1.Lefebvre, P., Cariou, B., Lien, F., et al.Role of bile acids and bile acid receptors in metabolic regulationPhysiol. Rev.89(1)147-191(2009) 2.Khurana, S., Raina, H., Pappas, V., et al.Effects of deoxycholylglycine, a conjugated secondary bile acid, on myogenic tone and agonist-induced contraction in rat resistance arteriesPLoS One7(2)e32006(2012) 3.Shang, Q., Guo, G.L., Honda, A., et al.Bile acid flux through portal but not peripheral veins inhibits CYP7A1 expression without involvement of ileal FGF19 in rabbitsAm. J. Physiol. Gastrointest. Liver Physiol.307(4)G479-G486(2014) 4.Woolbright, B.L., McGill, M.R., Staggs, V.S., et al.Glycodeoxycholic acid levels as prognostic biomarker in acetaminophen-induced acute liver failure patientsToxicol. Sci.142(2)436-444(2014) 5.Comhair, S.A.A., McDunn, J., Bennett, C., et al.Metabolomic endotype of asthmaJ. Immunol.195(2)643-650(2015)