Effect of hyperbaric oxygen on HIF-1αexpression in rat experimental pe-riodontitis with psychological stress / 中国病理生理杂志

ABSTRACT

[ ABSTRACT] AIM:To investigate the effect of hyperbaric oxygen ( HBO) on hypoxia-inducible factor-1α( HIF-1α) expression in rat experimental periodontitis with psychological stress.METHODS:Male special pathogen-free Wistar rats ( n=120) were randomly divided into 4 groupsnormal control group;psychological stress stimulation group;experi-mental periodontitis group the periodontitis model was induced by wrapping 3/0 silk ligature inoculated with Porphy-romonas gingivalis around the left maxillary second molar of the rats;periodontitis model with stress stimulation group.Psy-chological stress was removed at the 9th weeks after ligature, 6 rats from each experiment group were randomly chosen to HBO treatment.The rats were sacrificed at the 2nd, 4th, 8th and 10th weeks after ligature.Gingival index ( GI) and at-tachment loss (AL) were measured before sacrifice.The histological changes of periodontal tissues were observed under microscope with HE staining.The expression of HIF-1αwas observed by the method of immunohistochemistry.RE-SULTSThe sites of gingival attachment were normal in control group and psychological stress stimulation group.Periodon-tal pocket, and periodontal attachment loss were observed in experimental periodontitis group.The tissue damage was much serious in periodontitis model with stress stimulation group.No significant difference of GI and AL among psychological stress stimulation group and normal control group during the experiment was observed.GI and AL in periodonitis model with stress stimulating group were significantly higher than those in experimental periodontitis group at the 4th and 8th weeks (P<0.01).The levels of GI and AL were significantly lower at the 10th weeks after HBO treatmnt than those in untreated groups (P<0.05).No significant difference of HIF-1αexpression scores among psychological stress stimulation group and normal control group was found.HIF-1αexpression scores in periodonitis model with stress stimulating group was signifi-cantly higher than that in experimental periodontitis group at the 4th and 8th weeks (P<0.01).At the 10th weeks after HBO treatment the levels of HIF-1αwere significantly lower than that in untreated groups (P<0.01).CONCLUSION:Stress stimulation may aggravate periodontitis by decreasing tissue oxygenation in rats.HBO may represent a useful way in psychological stress periodontitis therapy.