Objective To investigate the expression patterns of CD133+ endothelial progenitor cell（EPC） on Wister rats during experimental tooth movement. Methods 40 Wistar rats’teeth movement models were established and divided into experiment group and control group. After loading 1, 3, 5, 7, 14 days killed them respectively. The histological sections were stained with hematoxylin-eosin and rabbit anti-rat CD133 polyclonal antibody to express CD133 immunoreactivity. Results Expression of CD133 in the new vessels did not appear in control group. In the early experiment, the expression of CD133 was discovered in the new vascular endothelial cells of periodontium in experiment group. Expression of CD133 got the maximum after loading 1 day in experiment group, then decreased gradually, but it was not significantly higher than control group（P >0.05）. Conclusion CD133 + EPC participated vascularized reaction in periodontal tissue of rat during the experimental tooth movement, direct participation was few and indirect effects possibly existed.
