Calcifediol

Calcifediol (DCI), also known as calcidiol, 25 hydroxycholecalciferol, or 25-hydroxyvitamin D (abbreviated 25 (OH) D), is a prohormone produced in the liver by hydroxylation of vitamin D3 (cholecalciferol ) by the cholecalciferol-25-hydroxylase enzyme. Calcifediol is then converted into the kidneys (by the enzyme 25 (OH) D-1α-hydroxylase) in calcitriol (1,25 - (OH) 2D3), a secosteroid hormone that is the active form of vitamin D. Also can be converted into 24 hydroxycalcidiol in the kidneys through 24-hydroxylation.

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