Metabolism of 25-hydroxyvitamin D3 by rat kidney cells in culture: isolation and identification of cis- and trans-19-nor-10-oxo-25-hydroxyvitamin D3.
A primary confluent culture of epithelial cells from rat kidney has been developed. These cells possess a 3.2-3.4 S high-affinity, low-capacity binding protein for 1,25-dihydroxyvitamin D3. They metabolize 25-hydroxyvitamin D3 to at least five metabolites. Two have been identified as 1,25-dihydroxyvitamin D3 and 24,25-dihydroxyvitamin D3. Two others have been identified by means of physical data and cochromatography as trans 19-nor-10-oxo-25-hydroxyvitamin D3 and the other as its cis isomer. These two "metabolites" have not been observed in vivo, but one of them (cis) comigrates with 1,25-dihydroxyvitamin D3 on straight-phase high-performance liquid chromatography. Thus, mere cochromatography on high-performance liquid chromatography is not sufficient to identify critical vitamin D metabolites.
D000818:Animals; D001711:Biotransformation; D002112:Calcifediol / Q000031:analogs & derivatives* / Q000302:isolation & purification / Q000378:metabolism*; D002478:Cells, Cultured; D002645:Chickens; D002851:Chromatography, High Pressure Liquid; D007668:Kidney / Q000378:metabolism*; D008297:Male; D051381:Rats; D013057:Spectrum Analysis / Q000379:methods; D013237:Stereoisomerism
C039030:19-nor-10-keto-25-hydroxyvitamin D3; D002112:Calcifediol