title: 1alpha,25-dihydroxy-3-epi-vitamin D3: in vivo metabolite of 1alpha,25-dihydroxyvitamin D3 in rats.
abstract: We recently identified 1alpha,25-dihydroxy-3-epi-vitamin D3 as a major in vitro metabolite of 1alpha,25-dihydroxyvitamin D3, produced in primary cultures of neonatal human keratinocytes. We now report the isolation of 1alpha,25-dihydroxy-3-epi-vitamin D3 from the serum of rats treated with pharmacological doses of 1alpha,25-dihydroxyvitamin D3. 1alpha,25-dihydroxy-3-epi-vitamin D3 was identified through its co-migration with synthetic 1alpha,25-dihydroxy-3-epi-vitamin D3 on both straight and reverse phase high performance liquid chromatography systems and by mass spectrometry. Along with 1alpha,25-dihydroxy-3-epi-vitamin D3, other previously known metabolites, namely, 1alpha,24(R),25-trihydroxyvitamin D3, 1alpha,25-dihydroxy-24-oxo-vitamin D3 and 1alpha,25-dihydroxyvitamin D3-26,23-lactone, were also identified. Thus, our study for the first time provides direct evidence to indicate that 1alpha,25-dihydroxy-3-epi-vitamin D3 is an in vivo metabolite of 1alpha,25-dihydroxyvitamin D3 in rats.
authors.affiliation: Department of Pediatrics, Women and Infants Hospital of Rhode Island, Brown University School of Medicine, Providence 02905, USA.
authors.forename: H
authors.initials: H
authors.lastname: Sekimoto
authors.forename: M L
authors.initials: ML
authors.lastname: Siu-Caldera
authors.forename: A
authors.initials: A
authors.lastname: Weiskopf
authors.forename: P
authors.initials: P
authors.lastname: Vouros
authors.forename: K R
authors.initials: KR
authors.lastname: Muralidharan
authors.forename: W H
authors.initials: WH
authors.lastname: Okamura
authors.forename: M R
authors.initials: MR
authors.lastname: Uskokovic
authors.forename: G S
authors.initials: GS
authors.lastname: Reddy
mesh_terms: D000818:Animals; D002762:Cholecalciferol / Q000031:analogs & derivatives / Q000378:metabolism*; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D050356:Lipid Metabolism; D008297:Male; D013058:Mass Spectrometry; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000378:metabolism
chemical_list: C118756:dihydroxy-vitamin D3; D014807:Vitamin D; D002762:Cholecalciferol