Stimulation by retinoids of the natriuretic peptide system of osteoblastic MC3T3-E1 cells

The effects were examined of treatment with retinoids of osteoblastic MC3T3-E1 cells on the natriuretic peptide system that promotes the differentiation of osteoblastic cells. Northern blot analysis revealed high levels of mRNA for the retinoid X receptor beta (RXR beta) and moderate levels of mRNAs for retinoic acid receptors alpha (RAR alpha) and gamma (RAR gamma). Exposure of MC3T3-E1 cells to 1 microM retinoid caused increases in the levels of C-type natriuretic peptide (CNP) and natriuretic peptide receptor-C (NPR-C). The activity of natriuretic peptide receptor-B (NPR-B) was unchanged after the addition of retinoid to the culture system. These results suggest that retinoids might influence the metabolism of osteoblastic cells through regulation of the natriuretic peptide system.