title: [Excessive fluoride inducing calcium overload and apoptosis of ameloblasts].
abstract: OBJECTIVE
  To study the effect of excessive fluoride on calcium overload and apoptosis in cultured rat ameloblasts in vitro.
  
  
  METHODS
  Logarithmic-phase ameloblasts (HAT-7) were treated with 0, 0.4, 0.8, 1.6, 3.2, and 6.4 mmol · L(-1) sodium fluoride (NaF) solution. Cell activities were detected by using a Cell Counting Kit 8 (CCK-8) assay after 48 h of treatment. The effect of fluoride on cell apoptosis was analyzed by using flow cytometry. Excessive fluoride-induced calcium concentration and calreticulin expression changes in ameloblasts were detected by using laser scanning confocal microscopy, Western blot analysis, and real-time quantitative polymerase chain reaction.
  
  
  RESULTS
  NaF inhibited ameloblast activity at 1.6, 3.2, and 6.4 mmol · L(-1) (dose-dependent) after 48 h of induction. The Ca2+ fluorescence intensity of HAT-7 cells incubated with 1.6 and 3.2 mmol · L(-1) NaF was higher than that in the control group. The fluoride-induced early-stage apoptosis of ameloblasts after 48 h of induction and the early-stage apoptosis rate was positively correlated with fluoride concentration. Calreticulin mRNA expression in HAT-7 cells was higher than that in the control group after 48 h of incubation with 0.8, 1.2, and 1.6 mmol · L(-1) NaF.
  
  
  CONCLUSIONS
  Excessive fluoride-induced calcium overload in ameloblasts and further caused endoplasmic reticulum stress-mediated apoptosis.
authors: Zhang
authors: Z
authors: Ying
authors: Ma
authors: M
authors: Lin
authors: Li
authors: L
authors: Jian
authors: Zhong
authors: Z
authors: Ming
authors: Zhang
authors: Z
authors: Kaiqiang
authors: Gu
authors: G
authors: Hefeng
mesh_terms: D000565:Ameloblasts; D000818:Animals; D017209:Apoptosis; D002118:Calcium; D002124:Calcium Fluoride; D005459:Fluorides; D010710:Phosphates; D051381:Rats; D012969:Sodium Fluoride
chemical_list: D010710:Phosphates; C012980:fluorophosphate; D012969:Sodium Fluoride; D002124:Calcium Fluoride; D005459:Fluorides; D002118:Calcium