the in vivo effect of pth on renal 24-hydroxylase activity of 25-hydroxyvitamin d3 ( 25ohd3 ) was examined in vitamin d-deficient thyroparathyroidectomized rats by a recently developed sensitive in vitro assay of 25ohd3-hydroxylases using rat kidney homogenates and by an in vivo assay measuring the accumulation of tritiated metabolites in plasma 5 h after injection of 25oh [ 3h ] d3 .
C0042870
vitamin d-deficient
C2713074
25ohd3