Recommended intake of vitamin D2 is not as effective as vitamin D3 in recovering serum 25OHD in vitamin D insufficient Sham and OVX rats.

FRIEDMAN S; MAROTTE C; GONZALES CHAVES M; BRYK G; PELLEGRINI G; ZENI SN

Toronto, Canada

Congreso; ASBMR 2010 Annual Meeting; 2010

ASBMR

D3 according to previous works is almost twice more potent than D2 in raising 25OHD levels (J Clin Met endoc 93:3015, 2008). We performed a study using our model of vit D insufficiency in adult SHAM and OVX rats refeeding with 2 isocaloric diets that supplied the recommended dietary vitamin D intake which only differed in the source of vit D (Bone 39: 837-844, 2006). During 15 days post-surgery all rats fed a diet containing 15% protein, 200IU% vit D and 0.6% calcium followed by an additional period of 45 days with diet lacking of vit D (0 IU%) to obtain vit D insufficiency. After the105-days, rats were divided into 4 groups that fed a diet containing 100UI% of D2 (OVX+D2 and SHAM+D2) or D3: (OVX+D3 and SHAM+D3). Baseline, 60, 85 and 105 days serum 25HOD (ng/ml) levels were measured in each group by a methodology recognized both 25OHD3 and 25OHD2 (125I RIA Kit, DiaSorin, Stillwater, MN, USA). Results of SHAM and OVX rats are show in figures 1 and 2, respectively. (*) p< 0.01 compared to baseline and (**) p<0.05 compared to D2 Conclusions: Under our experimental conditions, recommended dietary intake of vitamin D supplied by adding D3 in the diet is more effective than supplying D2 in raising 25OHD levels during a 45 day period in both estrogen conditions. PIP 6483