RESUMEN
Objective To explore the effects of chronic fluorosis on neurons in the cerebral cortex of rats,and to provide some morphological evidence of damage in the central nervous system induced by chronic fluorosis.Methods Male Wistar rats 40 days after birth were fed with high fluoride contented water(100 mg/L)for inducing chronic fluorosis.Immunocytochemistry and in situ hybridization were used to detect c-fos and Caspase 8 at cerebral cortical neurons respectively.Results c-fos positive cells rate and gray scale in the cerebral cortex of chronic fluorosis were 35.8%and 0.2756±0.0241,respectively,and that of control group were 32.1%and 0.2774±0.0331with statistical difference(χ2=0.305,t=0.826,P＞0.05).Caspase 8 positive cells rates of fluorosis group and control group were 18.7%and 14.1%,respectively,the difference being statistically significant(χ2=0.419,P＞0.05).The gray scale of fluorosis group and control group were 0.3874±0.0329 and 0.3884±0.0323,respectively,the difference being statistically significant(t=0.641,P＞0.05).Conclusion Chronic fluorosis had no significant influence on apoptosis of cerebral cortical neurons.