Fig. 3. Effect of RA on F-actin and paxillin contacts formation in MC3T3-E1 preosteoblasts on Ti surface. MC3T3-E1 preosteoblasts on the Ti discs were incubated in serum-free α-MEM with or without 14 µg/ml RA. These cells were fixed and stained using immunofluoresce for fluorescence microscopy. (A) F-actin formation. (B, C) The number of paxillin contacts. All scale bars are 10 µm. RA: rosmarinic acid, Ti: titanium. *p<0.05, compared to control.