In vivo 24-hydroxylation of 25-hydroxyvitamin D3 in enterocolectomized rats.
To determine if the renal 25-hydroxyvitamin D3 24-hydroxylase is active in addition to the intestinal 25-hydroxyvitamin D3 24-hydroxylase in vivo in the rat, radiolabeled 25-hydroxyvitamin D3 was administrated to normocalcemic, vitamin D-replete, enterocolectomized rats. Substantial amounts of 24,25-dihydroxyvitamin D3 were detected and the identity of the isolated plasma 24,25-hydroxyvitamin D3 region in these animals were confirmed by coelution on high pressure liquid chromatography and periodate cleavage. This suggests that both intestinal and renal 25-hydroxyvitamin D3 24-hydroxylases are active in vivo in the rat.
D015090:25-Hydroxyvitamin D3 1-alpha-Hydroxylase / Q000378:metabolism*; D000818:Animals; D003106:Colon / Q000502:physiology*; D004386:Duodenum / Q000502:physiology*; D006887:Hydroxycholecalciferols / Q000378:metabolism*; D007422:Intestines / Q000201:enzymology; D007668:Kidney / Q000201:enzymology*; D008297:Male; D051381:Rats; D013250:Steroid Hydroxylases / Q000378:metabolism*
D006887:Hydroxycholecalciferols; D013250:Steroid Hydroxylases; D015090:25-Hydroxyvitamin D3 1-alpha-Hydroxylase