Expression of MMP-2 in periodondal tissue of ovariectomized rats with periodontitis

Objective To study the correlation between estrogen level and periodontitis. Methods Thirty female Wister rats were randomly divided into control group,sham operation group and ovariectomized group.A model of rat periodontitis was established by ligating the second molar of rats in sham and ovariectomized groups with a silk thread.Expression of MMP-2 in periodontal tissue of rats in 3 groups was detected with immunohistochemistry. Results The MMP-2 was strongly and weakly expressed in ovariectomized group and sham operation group,respectively,but nearly not expressed in control group.The mean optical density was significantly higher in sham operation group and ovariectomized group than in control group（P＜0.05）,and in ovariectomized group than in sham operation group（P＜0.05）. Conclusion The expression level of MMP-2 is higher in periodontal tissue of rats with a lower estrogen level than in periodontal tissue of rats with a normal estrogen level,indicating that a lower estrogen level can exacerbate the disruption of periodontal tissue.