the conversion of circulating 25-hydroxyvitamin d3 ( 25ohd3 ) to its active metabolite 1,25-dihydroxyvitamin d3 [ 1,25- ( oh ) 2d3 ] in the renal tubule mitochondrion by the enzyme 25ohd3-1 alpha-hydroxylase is closely regulated in vivo according to the physiological need for calcium and phosphorus .
C0006657
25-hydroxyvitamin d3
C2713074
25ohd3