Abstract:
:A vitamin D(3) metabolite in intestine more polar than 25-hydroxy-vitamin D(3)(25-OH D(3)) has been detected by countercurrent distribution. The intestinal metabolite is found also after administration of labeled hydroxy D(3), indicating that it arises from vitamin D(3) via the intermediate 25-hydroxy derivative. The more polar metabolite is localized in the nuclear-chromatin fraction and appears in the gut before the physiological response to vitamin D(3).3.5 mug of the intestinal metabolite was isolated from 1250 chickens; the resulting purified material proved to be a potent mediator of calcium absorption. On a weight basis, it was at least 5 times as effective as vitamin D(3), and acted 3 times faster than either hydroxy D(3) or D(3) in stimulating intestinal calcium transport in the rachitic chick. It is proposed that this as yet uncharacterized steroid represents the active form of vitamin D(3) in the intestine.
journal_name
Proc Natl Acad Sci U S Aauthors
Haussler MR,Boyce DW,Littledike ET,Rasmussen Hdoi
10.1073/pnas.68.1.177subject
Has Abstractpub_date
1971-01-01 00:00:00pages
177-81issue
1eissn
0027-8424issn
1091-6490journal_volume
68pub_type
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