title: Measuring gluconeogenesis using a low dose of 2H2O: advantage of isotope fractionation during gas chromatography.
abstract: The contribution of gluconeogenesis to glucose production can be measured by enriching body water with (2)H(2)O to approximately 0.5% (2)H and determining the ratio of (2)H that is bound to carbon-5 vs. carbon-2 of blood glucose. This labeling ratio can be measured using gas chromatography-mass spectrometry after the corresponding glucose carbons are converted to formaldehyde and then to hexamethylenetetramine (HMT). We present a technique for integrating ion chromatograms that allows one to use only 0.05% (2)H in body water (i.e., 10 times less than the current dose). This technique takes advantage of the difference in gas chromatographic retention times of naturally labeled HMT and [(2)H]HMT. We discuss the advantage(s) of using a low dose of (2)H(2)O to quantify the contribution of gluconeogenesis.
authors.affiliation: Department of Biochemistry, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, Ohio 44106, USA.
authors.forename: Jill
authors.initials: J
authors.lastname: Katanik
authors.forename: Brendan J
authors.initials: BJ
authors.lastname: McCabe
authors.forename: Daniel Z
authors.initials: DZ
authors.lastname: Brunengraber
authors.forename: Visvanathan
authors.initials: V
authors.lastname: Chandramouli
authors.forename: Fumie J
authors.initials: FJ
authors.lastname: Nishiyama
authors.forename: Vernon E
authors.initials: VE
authors.lastname: Anderson
authors.forename: Stephen F
authors.initials: SF
authors.lastname: Previs
mesh_terms: D000818:Animals; D002247:Carbon Isotopes; D005591:Chemical Fractionation; D003903:Deuterium; D017666:Deuterium Oxide / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D008401:Gas Chromatography-Mass Spectrometry; D005943:Gluconeogenesis; D008297:Male; D008709:Methenamine; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D002247:Carbon Isotopes; D003903:Deuterium; D008709:Methenamine; D017666:Deuterium Oxide