Endocrine Abstracts

Vitamin D metabolites such as 25-hydroxyvitamin D (25D) circulate bound primarily to vitamin D binding protein (DBP). However, for most extra-renal tissues 25D uptake is independent of DBP, even though the ‘free’ 25D fraction is very small. DBP has a lower binding affinity for 25D2 compared to 25D3. We hypothesized that this would increase serum free 25D2, with possible variations in vitamin D function. Mice were placed on diets containing equal amounts (1000 IU/kg) ...