[Studies on DNA damage and apoptosis in rat brain induced by fluoride].
OBJECTIVE
To explore the DNA damage effects and apoptosis in brain cells of rats induced by sodium fluoride.


METHODS
SD rats were divided into two groups, i.e. control group and fluoride treated group, which were injected intraperitoneally with distilled water and sodium fluoride (20 mg.kg(-1).d(-1)) respectively. On the hand, 5 mmol/L NaF were used in in vitro study. Single Cell Gel Electrophosis (SCGE or Comet Assay) was utilized to measured DNA damage and apoptosis was detected by the TUNEL method and Flow Cytometry (FCM).


RESULTS
The DNA damage in pallium neurons in rats of the fluoride group was much more serious compared with those of the control group, with the Ridit value being 0.351 and 0.639 respectively (P < 0.01) in vivo, and 0.384 4 and 0.650 1 respectively (P < 0.01) in vitro. TUNEL positive cells were found in pallium, hippocampus and cerebellar granule cells in rats of fluoride group, whereas those in the control group were rare. It was demonstrated by FCM results that the percentages of apoptotic cells both in pallium and hippocampus were significantly higher (P < 0.01) in rats of fluoride group (27.12 +/- 3.08, 34.97 +/- 5.46) than those in control group (4.63 +/- 0.98, 5.35 +/- 0.79), (P < 0.01).


CONCLUSIONS
Sodium fluoride could induce DNA damage and apoptosis in rats brain.
Chen
Jun
J
Department of Environmental Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
Chen
Xuemin
X
Yang
Kedi
K
Xia
Tao
T
Xie
Hong
H
D000818:Animals; D017209:Apoptosis / Q000235:genetics*; D001921:Brain / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D020552:Comet Assay; D004247:DNA / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D005434:Flow Cytometry; D020287:In Situ Nick-End Labeling; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012969:Sodium Fluoride / Q000494:pharmacology*
D012969:Sodium Fluoride; D004247:DNA