|Langub jr, M|
|Reinhardt, Timothy - Tim|
Submitted to: Society for Neuroscience Abstracts and Proceedings
Publication Type: Abstract only
Publication Acceptance Date: 10/27/1997
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: 1,25-Dihydroxyvitamin D3 is a seco-steroid whose bioactivity is characterized by interaction with an intracellular receptor, the VDR. It has been suggested that the brain contains VDR and its mRNA has been reported to be decreased in hippocampi of patients diagnosed with Alzheimer's disease. However, localization of VDR and its functional implication have yet to be established in brain. Immunocytochemistry, Western blot and gel shift analyses were employed in the present study to characterize the VDR in rat hippocampus. The results indicated VDR immunoreactivity (IR) exclusively in cell nuclei of hormone-treated rats. Labeled cells were seen throughout the rostro-caudal extent of the hippocampus. VDR-IR was in the granule cells and in some cells of the molecular layer of the dentate gyrus and its hilus. The dorsal subiculum and CA1 also contained VDR-IR, as well as CA1, CA2 and some CA3 cells at the temporal and caudal levels. Using an antibody to glial fibrillary acidic protein, we confirmed by double labeling that glia also have VDR. Western blot and gel shift analyses of hippocampal extracts showed that VDR protein was present and capable of interacting with a vitamin D response element in a specific manner. These data suggest that the vitamin D hormone contributes to hippocampal function through the VDR and its gene regulatory properties. Forthcoming studies will examine the emerging importance of the VDR in brain function.