conversion of circulating 25-hydroxyvitamin d3 ( 25 ( oh ) d3 ) to its active metabolite 1,25-dihydroxyvitamin d3 ( 1,25 ( oh ) 2d3 ) occurs in the renal tubule mitochondrion .
C0006657
25-hydroxyvitamin d3
C2713074
25 ( oh ) d3