Methods: Osteoblasts were pre-cultured with F12 medium containing bFGF with different concentration and planted on the sand blasting titanium disks. Affection of bFGF with different concentration on osteoblastic attachment to titanium disk surfaces at different time were observed and analyzed by Scanning Electric Microscope(SEM) and MTT. mRNA expression of integrin subunit alpha2,5,beta1 were examined by immunofluorescent quantitative real-time polymerase chain reaction. The cytoskeleton proteins were observed by laser confocal microscope and immunofluorescence and analyzed quantitatively.
Results: The quantity of attached osteoblasts on the titanium disks increased apparently at 0.5h, 1h, and 2h. bFGF propelled the quantity of attached osteoblasts and spreading of the osteoblasts. The mRNA expression of itg beta1 was most abundant and the mRNA expressions of alpha2,5 were relatively lower than itg beta1. In the observation period, expression levels of Itg alpha2,5 and Itgbeta1 mRNA were up-regulated to different degree in the study group of 9ng/ml and 27ng/ml bFGF. In the group of 27ng/ml bFGF, the content of microfilament protein F-actin increased apparently according to control group. Expression levels of Itg alpha2,5 and Itg beta1 mRNA and F-action content showed time-dependent trend.
Conclusion: Integrin expression in rat osteoblastic cells is differentially modulated by bFGF in a time-dependent manner that is sensitive to the surface on which the cells are grown.