Level of oxidative stress in rat brains and learning and memory function of rats with chronic fluorosis / 中国地方病学杂志

ABSTRACT

Objective To investigate the changes of oxidative stress level in brain tissues and serum, and learning and memory in rats with oxidative stress level in nerve damage in chronic fluorosis. Methods The rats were randomly divided into 3 groups according to the body weight, eight rats in each group, i.e., control group, drinking water containing less than 0.5 mg/L of fluoride; lower fluoride exposure group, drinking water containing 5 mg/L of fluoride; higher fluoride exposure group, drinking water containing 50 mg/L of fluoride. The animals were examined six months after initiating the experiment. The total antioxidant capacity (T-AOC) and malondialdehyde (MDA), as well as learning and memory, were measured. Results Escape latency in higher fluoride exposed group[ (14.37±3.48)s] was significantly higher than that of controls[ (5.84±1.87)s] and exposed te lower fluoride [ (7.18±1.42)s], the difference being statistically signifieant(P<0.05). As compared with controls[ (2.17±0.11)× 103 U/L , (0.79±0.11)×103 U/g Pr] ,the rats exposed to higher fluoride and lower fluoride exhibited lower levels of T-AOC [(1.37±0.27)×103 U/L,(0.24±0.06)×103 U/g Prand (1.20±0.14) x 103 U/L,(0.41 ~ 0.10)×103 U/g Pr], the difference being statistically signifieant(P<0.05). As compared with controls[ (2.34±0.16) mmoL/L, (2.97±0.11)mmol/g Pr] and low fluoride exposed group[ (2.68±0.33)mmoL/L, (3.38±0.21)mmol/g Pr], higher level of MDA were observed in higher fluoride exposed group[ (3.72±0.59)retool/L, (4.01±0.21)mmol/g Pr], the difference being statistically significant(P<0.05). Conclusion The results indicated that higher amount of fluoride induced an increased level of oxidation, which might result in the decreased capacity of intelligence of rats with fluorosis.