title: Incorporation of a phosphonium analogue of choline into the rat brain as measured by magnetic resonance spectroscopy.
abstract: A clear understanding of choline metabolism is important in our goal to modify demyelination and remyelination in multiple sclerosis. To develop a technique capable of measuring metabolic changes in the brain, we have studied the incorporation of a phosphonium analogue of choline (P-choline) in tissue extracts of rats. After feeding adult rats a choline-deficient diet supplemented with P-choline, the analogue was not detectable by in vivo volume-localized 1H spectroscopy. However, in vitro 31P measurements of brain extracts revealed an 11% incorporation of P-choline into phosphatidylcholine. We report that P-choline incorporates preferentially into the lipid pool over the lipid precursor pool and we provide evidence that the choline peak resolved by in vivo 1H spectroscopy is only composed of small molecular weight choline-containing compounds.
authors.affiliation: University of Washington, Department of Radiology, Seattle 98195, USA.
authors.forename: J V
authors.initials: JV
authors.lastname: Jiménez
authors.forename: T L
authors.initials: TL
authors.lastname: Richards
authors.forename: A C
authors.initials: AC
authors.lastname: Heide
authors.forename: J R
authors.initials: JR
authors.lastname: Grierson
authors.forename: E G
authors.initials: EG
authors.lastname: Shankland
mesh_terms: D000818:Animals; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D002794:Choline / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism*; D002796:Choline Deficiency / Q000378:metabolism; D003404:Creatinine / Q000378:metabolism; D005997:Glycerylphosphorylcholine / Q000378:metabolism; D006859:Hydrogen; D009682:Magnetic Resonance Spectroscopy; D008970:Molecular Weight; D009186:Myelin Sheath / Q000378:metabolism; D009943:Organophosphorus Compounds / Q000737:chemistry / Q000378:metabolism*; D010713:Phosphatidylcholines / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism; D010759:Phosphorus Isotopes; D010767:Phosphorylcholine / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D014020:Tissue Extracts
chemical_list: D009943:Organophosphorus Compounds; D010713:Phosphatidylcholines; D010743:Phospholipids; D010759:Phosphorus Isotopes; D014020:Tissue Extracts; C015444:phosphonium phosphatidylcholine; D010767:Phosphorylcholine; D001224:Aspartic Acid; C093663:phosphonium choline; D005997:Glycerylphosphorylcholine; D006859:Hydrogen; C000179:N-acetylaspartate; D003404:Creatinine; D002794:Choline