Vasoactive peptide-regulated gene expression during osteoblastic differentiation

The formation of bone occurs via a series of events that are regulated by v arious hormones and cytokines. We previously reported that endothelin (ET) inhibits the mineralization by osteoblastic cells and natriuretic peptide ( NP) promotes osteoblastic differentiation. Therefore, we attempted to ident ify the genes induced by ET or NP in mouse preosteoblastic MC3T3-E1 cells u sing the method known as differential display-polymerase chain reaction (DD -PCR) to understand the bone metabolism further. Consequently, we found tha t expression levels of mRNAs for fibronectin, type XII collagen, p160 Rho-a ssociated kinase (ROCK), caldesmon, calpain, nucleolin and a novel gene wit h a zinc finger motif are downregulated in osteoblasts by ET stimuli. We al so found that expression levels of mRNAs for eIF-4A and a novel gene are in creased by C-type natriuretic peptide (CNP) stimuli.