RESUMO
Objective To qualitatively analyze the expressions of key marker genes involved in osteogenic differentiation of bone marrow stromal cells (BMSCs) of mice at defined stages in vitro using real-time RT-PCR. Methods The BMSCs of mice were cultured in vitro and induced to osteoblasts for 7, 14, and 21 days. The total RNA was extracted from the cultured cells and the gene expression levels of collagenⅠ, bone alkaline phosphatase (APL), osteopontin (OPN) and bone sialoprotein (BSP) in the osteoblasts at the defined stages were determined by real-time RT-PCR. Results The ColⅠmRNA levels in 14 and 21 days were (0. 75?0. 04) and (0. 34?0. 03) times respectively of that in 7 days. ALP, OPN and BSP mRNA levels in 21 days were (19. 70?2. 36), (150. 12?9. 31) and (7. 73?0. 58) times of those in 7 days respectively. Conclusions ColⅠexpression levels tend to gradually decline while ALP, OPN and BSP levels gradually increase along with the culture time. Real-time RT-PCR is a reliable method for investigation of gene expressions in BMSCs cultured in vitro.