1. [Action of 1,25-dihydroxyvitamin D3 in the tooth germ. Modulations of receptor in the development].
- Author
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Hotton D, Davideau JL, Dupret JM, Pike JW, Mathieu H, and Berdal A
- Subjects
- Animals, Calbindins, Cell Differentiation drug effects, Male, Osteocalcin analysis, Rats, Rats, Inbred Strains, S100 Calcium Binding Protein G analysis, Tooth Germ cytology, Tooth Germ metabolism, Dihydroxycholecalciferols pharmacology, Receptors, Steroid analysis, Tooth Germ drug effects
- Abstract
The control of tooth development by 1,25-Dihydroxyvitamin D3 is analyzed by light- and electron-microscope immunocytochemistry and Northern-blotting in vitamin D-deficient rats. The receptor for 1,25-Dihydroxyvitamin D3, immunostained at the light microscope in all stem-cells, became immunodetectable only at the ultrastructural level in the ameloblasts which elaborate enamel and odontoblasts which synthetize dentin. Moreover, 1,25-Dihydroxyvitamin D3 induces an up-regulation specifically in these cells. In parallel, the calbindins-D9k, -D28k and osteocalcin, in contrast to the phosphoprotein, appear sensitive to vitamin D-deficiency. A single injection of 1,25-Dihydroxyvitamin D3 led to the increase of steady-state levels of the corresponding calbindin mRNAs. These data show that tooth constitutes a target-organ for 1,25-Dihydroxyvitamin D3, as other components of the phospho-calcic metabolism.
- Published
- 1991