摘要
目的 观察慢性氟中毒对大鼠大脑皮质神经细胞活性氧（ROS）水平和线粒体融合的影响,并分析二者间的关系.方法 选择SD大鼠120只,按性别和体质量随机分为3组：对照组、低氟组、高氟组,每组40只.对照组大鼠自由饮用自来水（含氟量〈0.5 mg/L）;低、高氟组分别饮用氟化钠（NaF）配制的含氟量为10.0、50.0 mg/L的自来水.分别于3、6个月时处死大鼠,采集大脑组织制作冰冻切片,采用荧光测定法检测皮质神经细胞ROS水平和线粒体形态变化.结果 3、6个月时各组大鼠大脑皮质神经细胞ROS荧光计数和Ⅱ型线粒体计数水平比较,差异有统计学意义（F值分别为3.07、3.06,3.05、3.07,P均〈0.05）.3个月时,与对照组（10.43±5.98、4.12±3.86）比较,高氟组大鼠大脑皮质神经细胞ROS荧光计数（25.48±6.09）和Ⅱ型线粒体计数（20.47±6.09）明显升高（P均〈0.05）,而低氟组（11.67±3.49、6.68±3.48）未见明显改变（P均〉0.05）;6个月时,与对照组（25.26±6.41、20.26±6.41）比较,低、高氟组大鼠大脑皮质神经细胞ROS荧光计数和Ⅱ型线粒体计数（63.02±8.15、65.60±7.40,49.33±8.61、53.10±6.95）均明显增高（P均〈0.05）.ROS荧光计数与Ⅱ型线粒体计数间呈明显正相关（r值分别为0.93、0.81,P均〈0.05）.结论 摄入过量的氟导致大鼠大脑皮质神经细胞氧化应激水平升高,线粒体融合功能障碍,这些改变与染氟时间和剂量密切相关.线粒体异常改变的机制可能与慢性氟中毒引起的氧化应激水平升高有关.
Objective To investigate the changes of reactive oxygen species（ROS） level and mitochondria fission-fusion-balance in cortical neurons of rats with chronic fluorosis and reveal the correlation between these two factors. Methods One hundred and twenty rats were randomly divided into 3 groups（control group, low-dose fluorosis group, high-dose fluorosis group） and 40 rats were in each group according to body weight and the experiments were carried out for 3 months or 6 months. The rats were fed with different concentrations of fluoride （NaF） to establish fluorosis models. Controls were fed with tap water（ 〈 0.5 mg/L）, experimental animals in low- or high-dose group were fed with water containing NaF 10.0,50.0 mg/L, respectively. The level of ROS and the morphology in mitochondria fission-fusion balance in neurons of the cortex of rat brains prepared with cortical frozen sections were detected with ROS fluorescent probe and MitoTracker RED probe, respectively. Results Significant differences of the level of ROS and the numbers of abnormal mitochondria in morphology in the cortical neurons were found between 3 groups at the experiment period of 3 month and 6 month（F= 3.07,3.06,3.05,3.07, all P 〈 0.05）. As compared with control group（10.43 ± 5.98,4.12 ± 3.86） at the experiment period of 3 month, the level of ROS and the numbers of abnormal mitochondria in morphology in the cortical neurons were obviously increased in high-dose fluorosis group（25.48 ± 6.09,20.47 ± 6.09, all P 〈 0.05）, whereas no significant changes were found in low-dose fluorosis group（11.67 ± 3.49,6.68 ± 3.48, all P〉 0.05）. Furthermore, the increases in both ROS level and abnormal numbers of mitochondria were significant observed in the cortical neurons of low-dose fluorosis group （63.02 ± 8.15, 49.33 ± 8.61） and high-dose fluorosis group（65.60 ± 7.40,53.10 ± 6.95） as compared with the control group （25.26 ± 6.41,20.26 ± 6.41） at the experimental period of 6 month （all P 〈 0.05）. The abnormal numbers of mitochondria correlated with ROS level（r = 0.93,0.81, all P 〈 0.05）. Conclusions Taking excessive amount of fluoride results in high level of oxidative stress and impaired the balance of mitochondrial fission-fusion,which is dependent on the feeding times and doses of fluoride. The mechanism of the mitochondrial abnormalities might be associated with the high level of oxidative stress induced by chronic fluorosis.
出处
《中国地方病学杂志》
CAS
CSCD
北大核心
2011年第3期256-260,共5页
Chinese Jouranl of Endemiology
基金
基金项目：国家自然科学基金（30760224）
科技部国际合作项目（2010DFB30530）
贵州省科技基金项目（黔省专合字[2009]80、TZJF-2008-53）
关键词
氟化物中毒
活性氧
线粒体
大鼠
脑
Fluoride poisoning
Reactive oxygen species
Mitochondria
Rats
Brain
