Merck, 17943-100UG, (24R)-24,25-Dihydroxyvitamin D3

General description
(24R)-24,25-Dihydroxyvitamin D₃ or secalciferol is produced in kidney. It is the one of the most active form of vitamin D and an essential circulating vitamin D₃ metabolite.
Application
(24R)-24,25-Dihydroxyvitamin D₃ has been used to assess its function(s) compared with that of 1α,25(OH)2D₃, during osteoblastic differentiation of primary human mesenchymal stem cells (hMSCs).
Biochem/physiol Actions
Cholecalciferol is an inactive form of vitamin D3 which undergoes various levels of hydroxylation to form active vitamin D3 analogs. 1α-Hydroxyvitamin D3 (alfacalcidol) is a synthetic analog that is metabolized to 1,25-dihydroxycholecalciferol, the biologically active form of vitamin D3. Other analogues of cholecalciferol result from different hydroxylations. 24R,25-Dihydroxyvitamin D3 is a catabolite of 25-Dihydroxyvitamin D3 and a putative regulator of developmental bone formation. 24R,25-Dihydroxyvitamin D3 is a substrate for renal 25-hydroxyvitamin D3 1 α-hydroxylase. 24R,25-Dihydroxyvitamin D3 is an endogenous regulator of apo A-I synthesis through a VDR-independent signaling mechanism and an inhibitor of Pi-induced apoptosis through Ca²⁺, PLD, and PLC signaling and through LPA-LPA1/3-G(αi)-PI(3)K-mdm2-mediated p53 degradation.
(24R)-24,25-Dihydroxyvitamin D₃ plays an essential role in calcium and phosphorus homeostasis. (24R)-24,25-Dihydroxyvitamin D₃ along with 1α,25(OH)2D3 stimulates bone metabolism.
Packaging
Bottomless glass bottle. Contents are inside inserted fused cone.