title: Identification of 8 alpha,25-dihydroxy-9,10-seco-4,6,10(19)-cholestatrien-3-one as a product of metabolism of 25-hydroxycholecalciferol by liver microsomes.
abstract: The ability of liver microsomes, sites of synthesis of 25-hydroxycholecalciferol, to further metabolize 25-hydroxycholecalciferol has been assessed. When liver microsomes were incubated with 25-hydroxycholecalciferol in the presence of cytosol, a metabolite was isolated that comigrated with 8 alpha,25-dihydroxy-9,10-seco-4,6,10(19)-cholestatrien-3- one in three different chromatographic systems. The ultraviolet spectrum (220-350 nm) and mass spectrum of the purified metabolite were identical to that of synthetic 8 alpha,25-dihydroxy-9,10-seco-4,6,10(19)-cholestatrien-3-one. This study indicates that liver microsomes convert 25-hydroxycholecalciferol to 8 alpha,25-dihydroxy-9,10-seco-4,6,10(19)-cholestatrien-3-one. The significance of this metabolite, which has been shown previously by others to be produced by alveolar macrophages, has yet to be determined.
authors.affiliation: Department of Biochemistry, Morehouse School of Medicine, Atlanta, Georgia 30310.
authors.forename: M
authors.initials: M
authors.lastname: Thierry-Palmer
authors.forename: K A
authors.initials: KA
authors.lastname: Richardson
authors.forename: H K
authors.initials: HK
authors.lastname: Schnoes
authors.forename: S
authors.initials: S
authors.lastname: Yamada
authors.forename: A L
authors.initials: AL
authors.lastname: Free
mesh_terms: D000818:Animals; D002112:Calcifediol / Q000378:metabolism*; D002782:Cholestenes / Q000302:isolation & purification* / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D008297:Male; D013058:Mass Spectrometry; D008862:Microsomes, Liver / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013056:Spectrophotometry, Ultraviolet
chemical_list: D002782:Cholestenes; C053021:8,25-dihydroxy-9,10-seco-4,6,10(19)-cholestatrien-3-one; D002112:Calcifediol