title: [Effect of fluoride on the viability and apoptosis of ameloblasts in vitro].
abstract: OBJECTIVE
  To evaluate the effect of fluoride on viability of rat ameloblasts in vitro.
  
  
  METHODS
  The ameloblasts of rat was exposed to different concentrations of NaF (0, 0.4, 0.8, 1.6, 3.2, 6.4 mmol/L) for 24, 48 and 72 hours. CCK-8 assays were performed to measure the cells proliferation; The morphology of apoptosis was observed by Hoechst 33258 staining and the rate of apoptosis was determined by flow cytometry. The data was analyzed using SPSS 13.0 software package.
  
  
  RESULTS
  (1)The proliferation of ameloblasts was increased when concentrations of NaF between 0.4 mmol/L and 0.8 mmol/L, whereas inhibited at 1.6 mmol/L NaF and above. The effects were in time-dependent manner.(2)Cells in the 1.6 mmol/L NaF groups showed unclear karyorrhexis and apoptotic cell morphology. The effects were in concentration-dependent manner.
  
  
  CONCLUSIONS
  (1)Fluoride has two-phase effects to ameloblasts: At low doses, it promoted cell proliferation while at high doses it had negative effects. (2)1.6 mmol/L NaF could induce apoptosis of ameloblasts.
authors.affiliation: Department of Preventive Dentistry, School of Stomatology, China Medical University. Shenyang 110002, Liaoning Province, China.E-mail:jrma6143@sina.com.
authors.forename: Lin
authors.initials: L
authors.lastname: Ma
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.forename: Ming
authors.initials: M
authors.lastname: Zhong
authors.forename: Li
authors.initials: L
authors.lastname: Zhu
authors.forename: Kai-qiang
authors.initials: KQ
authors.lastname: Zhang
authors.forename: He-feng
authors.initials: HF
authors.lastname: Gu
authors.forename: Lu
authors.initials: L
authors.lastname: Liu
authors.forename: Si-yu
authors.initials: SY
authors.lastname: Zhang
authors.forename: Rui-bo
authors.initials: RB
authors.lastname: Cheng
mesh_terms: D000565:Ameloblasts; D000818:Animals; D017209:Apoptosis; D049109:Cell Proliferation; D005459:Fluorides; D066298:In Vitro Techniques; D010710:Phosphates; D051381:Rats; D012969:Sodium Fluoride
chemical_list: D010710:Phosphates; C012980:fluorophosphate; D012969:Sodium Fluoride; D005459:Fluorides