Expression And Significance Of CXCR4in Bone Tissue Around Implants During Early Implantation

Objective:To investigate expression and significance of CXCR4in rat bone tissue around implants during early implantation, in order to provide theoretic direction to improve osseointegration during early implantation.Methods:Forty healthy Wistar rats of4months old which were composed of male and female in equal were selected and randomly divided into implantation6,12and24h groups and blank control group with10mice in each group. All rats except blank control group received anode-oxidized implant in one tibia and sand blast implant in the other one. Implant site was made in the tibia of rats in the blank control group, but no implants were implanted. Rats were killed6,12,24h after implantation, the implants were unscrewed, and bone tissue around implant in left and right tibia was prepared,2cm in diameter. For blank control group, diameter about2cm bone tissue around implant site in left and right tibia was prepared. Half tissue was made into protein samples. The amount of CXCR4expression was detected by Western blot with β-actin as control. The other half was dealt with neutral EDTA, then slides were made. CXCR4expression was detected by immunohistochemistry. The retrieved implants were examined by SEM. The value of IOD of Western blot was analyzed by Total Lab Quant software. The value of AIOD of immunohistochemistry was analyzed by IMAGE-PRO-PLUS software. With the experimental data (x±s) indication, statistical analysis was performed using SPSS13.0software package for Dunnett-t test and factorial analysis. The results are statistically significant based on P<0.05.Results:1. The results of Western blot indicated that the expression of P-actin is consistent in the experimental and blank control groups. The expression of CXCR4protein in implan-tation6,12and24h groups were obviously higher than blank control group. The value of CXCR4/|3-actin of implantation6,12and24h groups were significantly higher than blank control group(P<0.05).The value of CXCR4/β-actin in rat bone tissue around anode-oxidized implant was higher than blast implants at each time point during the24h implantation.2. The expression of CXCR4was observed mainly occurred in the cytoplasm and cytomembrane according to the results of immunohistochemistry. The expression of CXCR4protein in implantation6,12and24h groups were obviously higher than blank control group (P<0.05).The value of AIOD of CXCR4in rat bone tissue around anode-oxidized implant was higher than blast implants at each time point during the24h implantation.3. The results of SEM indicated that the surface of all retrieved implants of24h implantation group was covered by abundant fibrous, red blood cells and white blood cells. The anode-oxidized surface showed more attached mesenchymal-like cells scattered all over the surfaces. Conclusion:1. A large number of red blood cells, white blood cells, mesenchy mal-like cells were migrated to the implant site.2. The expression of CXCR4during the first24h of implantation was significantly higher than that of the blank control group, indicating that CXCR4positive cells take part in the regeneration of bone tissue during early osseointegration.3. The anode-oxidized implants induced higher expression of CXCR4, may promote the stability of implant at early time points.