The role of nitric Oxide in reparative dentin formation part I: The expression of nitric Oxide synthase
MEI Yu-feng,Department of Pedodontics,School of Stomatologly,Nanjing Medical University,Nanjing 210029,China
Objective:To Investigate the NOS expression in reparative dentinogenesis after tooth preparation.Method:The expression of NOSs in the odontoblasts and pulp cells was detected by immuno- histochemistry statining on crysection after the cavity prepartion on the mesial surface of the maxillary first molars of rats. Result:In normal rat molars, odontoblasts were endothelial NO synthase(eNOS)-positive,but inducible NOS(iNOS)-negative. Immediately after preparation, damaged odontoblasts were positive for both enzymes. iNOS was strongly observed in neutrophils after 1 day and in odontoblasts and whole pulp cells after 3 days. eNOS was expressed weakly in these cells after 1 to 3 days. After 7 days, they were negative for iNOS, but eNOS-positive odontoblasts were seen under the reparative dentin. Conclusion: These findings suggest that NO takes part in regulating odontoblasts in reparative dentinogenesis.