Discrepancy between serum concentrations of 1,25-dihydroxyvitamin D metabolites measured by radio-immunoassay and thymus radioreceptor assay during vitamin D2 treatment

D Hartwell, J S Johansen, C Christiansen
Scandinavian Journal of Clinical and Laboratory Investigation 1989, 49 (6): 545-53
A radio-immunoassay (RIA) for determination of 1,25-dihydroxycholecalciferol (1,25(OH)2D3) and 1,25-dihydroxyergocalciferol (1,25(OH)2D2) in serum was compared with a competitive protein binding assay using calf thymus receptor to clarify the comparability of measurements in subjects treated with either vitamin D2 or vitamin D3 (4000 IU per day for 8 weeks). Before and during treatment with vitamin D3 the two assay techniques were concordant, but during vitamin D2 treatment the serum concentrations of 1,25(OH)2D2 and 1,25(OH)2D3 were higher when measured by RIA. The study demonstrates that during vitamin D2 treatment unknown compounds, recognized only by the antiserum, co-elute with 1,25(OH)2D2 and 1,25(OH)2D3 in high pressure liquid chromatography. It can be concluded that the radio-immunoassay used here cannot replace the calf thymus receptor assay.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Trending Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"