SjÖgren, S., Bawden, J., HammarstrÖm, L.E.&Larsson,Å. No demonstrable accumulation of14C-vitamin D3in developing rat teeth and bones.Acta Odont. Scand. 36, 51–55The distribution of14C-vitamin D3administered subcutaneously in arachidic oil to 6-day-old suckling rats has been examined autoradiographically. The animals were sacrificed 1,2,4 and 8 days after injection. The autoradiographic exposure time was 4 months. The sectioning and exposure was performed in a freeze-room. Radioactivity was found mainly in the liver, kidney, intestines and fat depots. No uptake was found in developing teeth or bones.