Editorial: 24, 25-Dihydroxyvitamin D--Active Metabolite or Inactive Catabolite?
نویسندگان
چکیده
منابع مشابه
Measurement of mammalian 25 - hydroxyvitamin D 3 24 R - and la - hydroxylase ( 1 , 25 - dihydroxyvitamin D 3 / 24 , 25 - dihydroxyvitamin D / kidney / calcium ) YOKO TANAKA AND
An in vitro assay of mammalian 25-hydroxyvitamin D3 laand 24R-hydroxylases in kidney has been developed. It had been suggested that 25-hydroxyvitamin D binding protein present in mammalian blood and tissues inhibits the enzyme activities in cell-free preparations by binding the substrate 25-hydroxyvitamin D3 more strongly than the hydroxylases bind it. This inhibitory effect is overcome by the ...
متن کاملSimultaneous determination of 25-hydroxyvitamin D, 24,25-dihydroxyvitamin D, and 1,25-dihydroxyvitamin D in plasma or serum.
We describe a simultaneous assay for the principal vitamin D metabolites: 25-hydroxyvitamin D, 24-25-dihydroxyvitamin D, and 1,25-dihydroxyvitamin D. Special attention has been paid to simplification of the extensive extraction and purification procedures used in previously described simultaneous assays. All three metabolites were isolated with a single extraction step, followed by only one gra...
متن کاملBritain Stimulation of 1 , 25 - dihydroxyvitamin D 3 production by 1 , 25 - dihydroxyvitamin D 3 in the hypocalcaemic rat
Serum 1,25-dihydroxyvitamin D3 concentration and renal 25-hydroxyvitamin D 1 a-hydroxylase activity were measured in rats fed various levels of calcium, phosphorus and vitamin D3. Both calcium deprivation and phosphorus deprivation greatly increased circulating levels of 1,25-dihydroxyvitamin D3. The circulating level of 1,25-dihydroxyvitamin D3 in rats on a low-calcium diet increased with incr...
متن کاملEffect of 25 - hydroxyvitamin D 3 and 1 , 25 - dihydroxyvitamin D 3 maternal loads on maternal and fetal vitamin D metabolite
Two groups of female rats were used to investigate vitamin D metabolism in the pregnant animals and in their fetuses. In the first group, 3 wg of 25-hydroxyvitamin D3 (25-OH-D 3) per kg of body weight were injected into intact or nephrectomized (NX) pregnant rats 3 h before sacrifice on day 21 of pregnancy ; in the second group, 2 and 6 ng, respectively, of 1,25-dihydroxyvitamin D3 (1,2510H1 2)...
متن کاملKidney disease and vitamin D levels: 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, and VDR activation
A normal vitamin D status is essential for human health. Vitamin D deficiency is a recognized risk factor for all-cause mortality in normal individuals and in chronic kidney disease (CKD) patients. The link between vitamin D deficiency and death is a defective activation of the vitamin D receptor (VDR) by 1,25-dihydroxyvitamin D (calcitriol, the vitamin D hormone) to induce/repress genes that m...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Endocrinology
سال: 1998
ISSN: 0013-7227
DOI: 10.1210/en.139.8.3371