title: Identification of 24,25,26,27-tetranor-23-hydroxyvitamin D3 as a product of the renal metabolism of 24,25-dihydroxyvitamin D3.
abstract: By cochromatography, mass spectrometry, and chemical derivatization, we have shown that a metabolite isolated from the perfused rat kidney incubated with 24-(R),25-dihydroxyvitamin D3 is indistinguishable from chemically synthesized 24,25,26,27-tetranor-23-hydroxyvitamin D3. The new metabolite is also produced from 24-oxo-25-hydroxyvitamin D3 but not from 23(S),25-dihydroxyvitamin D3. Enzymes required for the synthesis of the new metabolite are absent in the vitamin D deplete animal but are induced along with the 25-hydroxyvitamin-D3 24-hydroxylase by vitamin D repletion. The pathway of 24,25-dihydroxyvitamin D3 metabolism in the perfused kidney is stimulated by pre-treatment of the rat with large doses of vitamin D3, suggesting that the pathway is a degradative one.
mesh_terms: D015650:24,25-Dihydroxyvitamin D 3; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004100:Dihydroxycholecalciferols / Q000378:metabolism*; D006887:Hydroxycholecalciferols / Q000302:isolation & purification*; D066298:In Vitro Techniques; D007202:Indicators and Reagents; D007668:Kidney / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D013058:Mass Spectrometry; D010477:Perfusion; D051381:Rats; D011919:Rats, Inbred Strains; D013053:Spectrophotometry
chemical_list: D004100:Dihydroxycholecalciferols; D006887:Hydroxycholecalciferols; D007202:Indicators and Reagents; D015650:24,25-Dihydroxyvitamin D 3; C043003:24,25,26,27-tetranor-23-hydroxyvitamin D3