摄氟对大鼠肝脏谷胱甘肽含量和磷酸化酶α活性的影响

给Ｗｉｓｔａｒ雄性大鼠自由饮用０．６ｍｇ／Ｌ（对照组），１００ｍｇ／Ｌ．２００ｍｇ／Ｌ含氟水，于染氟２，４，６周分批处死，测肝ＧＳＨ，ＭＤＡ含量和磷酸化酶α，同时测血清Ｃａ２＋浓度及磷酸化酶α活性，血浆总蛋白、球蛋白和白蛋白含量。结果显示，肝ＧＳＨ含量于染氟第２，４周显著降低；２００ｍｇ／Ｌ组大鼠肝磷酸化酶α活性于第２周显著降低；血浆白蛋白水平于染氟第６周显著降低。表明氟可引起肝细胞内钙稳态失调，并可致肝脂质过氧化作用增强。     

摄氟对大鼠肝脏谷胱甘肽含量和磷酸化酶a活性的影响

给Ｗｉｓｔａｒ雄性大鼠自由饮用０．６ｍｇ／Ｌ（对照组），１００ｍｇ／Ｌ，２００ｍｇ／Ｌ含氟水，于染氟２，４，６周分批处死，测肝ＧＳＨ，ＭＤＡ含量和磷酸化酶ａ，同时测血清Ｃａ＾２＾＋浓度及磷酸化酶ａ活性，血浆总蛋白，球蛋白和白蛋白含量。结果显增，肝ＧＳＨ含量于染氟第２，４周显著降低；２００ｍｇ／Ｌ组大鼠肝磷酸化酶ａ活性于第２周显著降低；血浆白蛋白水平于染氟第６周显著降低。表明氟可引起肝细胞内钙稳态失     

超氧化物歧化酶诱导剂促使氟中毒大鼠排泄氟的实验研究

ＳＤ大鼠７７只，随机分为７组：１组为阴性对照组，自由饮用自来水；２．３组分别为大、小剂量绞股蓝组４，５组分别为大、小剂量ＳＯＤ中药复方制剂组；６组为ＳＯＤ注射组；７组为慢性氟中毒阳性对照组，２～７组均自由饮用４８ｍｇ／Ｌ含氟水。实验结果：除第７组外，用药各组动物血清ＳＯＤ含量约恢复正常，与阴性对照组无明显差异，同时这些动物尿氟排出增加，与对照组有显著性差异（Ｐ＜０．０５）。结果表明用了ＳＯＤ诱导剂后；使氟中毒动物血清ＳＯＤ含量恢复，同时可促进尿氟排出增加。     

刺梨汁拮抗慢性氟中毒的实验观察

用含氟３２０ｍｇ／ｋｇ饲料和含维生素Ｃ６００ｍｇ／１００ｍｌ刺梨汁饮不饲养Ｗｉｓｔａｒ大鼠６个月，探讨刺梨汁对慢性氟中毒的影响及其机理。结果发现刺梨汁具有明显改善慢性氟中毒的一般状况，减少氟斑牙的形成，增加氟中毒大鼠的体重，促进尿氟排泄，降低血清和骨氟含量，提高血清维生素Ｃ含量，保护胶原组织，使尿羟脯氨酸含量降低，通过提高血清维生素Ｅ和ＧＳＨ含量，增强血ＧＳＨ－Ｐｘ和ＳＯＤ活性而抑制氟中毒引起的脂     

氟对大鼠子代脑单胺类神经介质的影响

Ｗｉｓｔａｒ大鼠自查到阴栓起，分别自由饮用０．６ｍｇ／Ｌ（对照组）、１ｍｇ／Ｌ、５ｍｇ／Ｌ、２５ｍｇ／Ｌ含氟水，其仔鼠饮用同浓度含氟水至９０ｄ，观察胚胎期及生长发育期接触氟对仔鼠大脑功能的影响。采用高压液相色谱－电化学法对大脑单胺类神经介质测定结果显示，除多巴胺的代谢产物之一－３，４－二羟乙酸（ＤＯＰＡＣ）的含量在高剂量组显著降低外，去甲肾上腺素（ＮＥ）、多巴胺（ＤＡ）、高香草酸（ＨＶＡ）、５－羟色胺（５－ＨＴ）和５－羟吲哚乙酸（５－ＨＩＡＡ）的含量与对照组比较均无显著差异，表明氟可抑制ＤＡ的代谢转化，对单胺氧化酶（ＭＡＯ）的活性有一定的抑制作用。提示氟对仔鼠的大脑功能有一定的不良影响。     

实验性氟中毒大鼠关节滑膜细胞的体视学研究

为探讨氟中毒对关节滑膜的损伤，用１２只Ｗｉｓｔａｒ大鼠随机分为对照组和实验组。实验大鼠饲以５０ｍｇ／Ｌ含氟水１２０ｄ后，取关节滑膜进行超微结构体视学检查。结果显示：氟中毒大鼠关节滑膜细胞体积缩小，线粒体肿胀、增生，与对照组比较，差异有显著性（Ｐ＜０．０５）。表明过量氟对滑膜细胞有损伤作用。     

抗氧化中药对氟中毒大鼠脑损伤的拮抗作用

Ｗｉｓｔａｒ大鼠１００只，随机分为３组：（１）正常对照组，自由饮用自来水；（２）氟中毒组，自由饮用含ＮａＦ２１１ｍｇ／Ｌ的加氟水；（３）复方中药组，自由饮用与氟中毒组浓度相同的加氟水，同时腹腔注射丹参—绞股蓝复方中药。结果显示：氟中毒组，脑组织、红细胞中超氧化物歧化酶（ＳＯＤ）活性比正常对照组低，丙二醛（ＭＤＡ）含量升高（Ｐ＜０．０１）；复方中药组上述指标与正常对照组比较无显著性差异（Ｐ＞０．０５）。表明过量氟能通过脂质过氧化作用增强而造成脑组织的损伤；丹参—绞股蓝复方中药对过量氟诱发自由基水平增高所引起的脑损伤有拮抗作用     

氟化物对大鼠脂代谢的影响

给５４积Ｗｉｓｔａｒ雄性大鼠自由饮用染氟水，浓度分别为０．６（对照组），１００和２００ｍｇ／Ｌ，于染氟后第２，４，６周分批处死，测血清和肝组织的胆固醇，甘油三酯含量。结果显示，染氟第６周，染氟组大鼠血清胆固含量显著增高，肝组织胆固醇含量显著降低。２００ｍｇ／Ｌ摄氟组大鼠血清甘油三酯含量在第４周显著降低，肝组织甘油三酯含量在第６周显著降低。提示，氟可影响大鼠脂代谢，引起高胆固醇血症。     

氟对大鼠的行为致畸学研究

Ｗｉｓｔａｒ大鼠自孕期分别自由饮用０．６ｍｇ／Ｌ（对照组）、１ｍｇ／Ｌ，５ｍｇ／Ｌ，２５ｍｇ／Ｌ含氟水，仔鼠亦饮用同浓度含氟水，观察仔鼠行为致畸学改变。结果表明仔鼠一般体格发育指标未见异常改变，但高剂量组行为发育呈现轻微的延迟效应，尤其是对运动和协调功能及肌力的影响较明显。２５ｍｇ／Ｌ组听觉惊愕反应的建立显著延迟。表明氟对行为发育有一定的延缓作用，但这种作用是可逆的，最终仍可达正常水平。结果尚证实氟对听神经发育有较明显的损伤作用。     

氟中毒大鼠血清碱性磷酸酶活性及钙,磷水平的动态变化

本实验复制了慢性氟中毒大鼠病理模型、对血清碱性磷酸酶（ＡＬＰａｓｅ）活性和钙、磷水平进行了动态观察。结果表明，血清碱性磷酸酶活性在中毒１４ｄ内升高，然后下降，在３０ｄ时达到谷底，到９０ｄ时又恢复到原水平。而血清钙、磷水平在１４ｄ以后才开始下降，３０ｄ达到谷底，９０ｄ恢复到原水平。这一变化规律在饮水含氟（ＮａＦ）达０．１ｍｇ／ｍＬ时最明显。本文用“Ｍｇ＾２＋假说”解释了这一变化规律。同时对氟中毒的损     

氟对大鼠骨组织3-磷酸肌醇激酶和蛋白激酶B1表达的影响

目的 观察慢性氟中毒对大鼠骨组织中3-磷酸肌醇激酶(PI3K)、蛋白激酶B1(Akt1)蛋白和mRNA表达的影响,探讨PI3K/Akt信号通路在氟骨症发病机制中的作用.方法 将36只SD大鼠按性别和体质量随机分为3组:对照组、低氟组、高氟组,每组12只.对照组自由饮用自来水(含氟量<0.5 mg/L),低、高氟组大鼠分别饮用氟化钠(NaF)配制的含氟量为5.0、50.0 mg/L的自来水.实验6个月后处死大鼠,收集血清,用酶联免疫吸附测定(ELISA)法检测骨钙素(BGP)、组织蛋白酶K(Cath-K).取大鼠股骨下段,用免疫组织化学方法和实时荧光定量PCR法检测骨组织中PI3K、Akt1蛋白和mRNA的表达.结果 各组大鼠血清BGP、Cath-K 水平比较,差异有统计学意义(F值分别为73.45、39.36,P均<0.05).与对照组[(0.15±0.03)μg/L、(18.32±2.27)pmol/L]比较,低、高氟组血清BGP[(1.99±0.62)、(2.38±0.16)μg/L]、Cath-K[(89.07±19.66)、(110.16±9.81)pmol/L]明显升高(P均<0.05),且高氟组明显高于低氟组(P均<0.05).各组大鼠骨组织PI3K、Akt1蛋白和mRNA表达水平比较,差异有统计学意义(F值分别为178.16、118.08,38.81、52.31,P均<0.05).与对照组(181.55±4.24、188.46±2.18,3.84±1.69、4.33±0.89)比较,低、高氟组大鼠骨组织PI3K(171.66±2.85、154.12±4.15,11.31±4.18、20.54±6.68)、Akt1蛋白和mRNA表达(177.47±3.16、156.42±3.18.12.52±3.13、19.43±5.36)明显增高(P均<0.05),且高氟组明显高于低氟组(P均<0.05).结论 血清BGP、Cath-K可作为慢性氟中毒骨病变的代谢指标.氟可导致大鼠骨组织中PI3K、Akt1蛋白和mRNA表达水平增高,PI3K/Akt 信号通路可能参与了氟引起的骨骼损伤机制.

Abstract：

Objective To observe the expression of phosphoinositide 3-kinase(PI3K) and protein kinase B1 (Akt1) in PI3K/Akt signaling pathway in rat bones with fluorosis, and to reveal the mechanisms of the skeletal fluorosis. Methods Thirty-six SD rats were randomly divided into 3 groups (control group, low-dose fluorosis group, high-dose fluorosis group) and 12 rats were in each group according to body weight. 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 groups were fed with water containing NaF 5.0,50.0 mg/L, respectively. Rats were sacrificed after 6 months of treating with fluoride and the serum was kept for testing the bone metabolic markers of none gla protein(BGP) and cathepsin K(Cath-K) by enzyme-linked immunosorbent assay(ELISA), the proteins and mRNA levels of PI3K and Akt1 in rat bones were detected by immunohistochemistry and real time PCR, respectively. Results Each group of serum BGP and Cath-k were compared, the difference was statistically significant(F = 73.45,39.36, all P < 0.05). The contents of BGP[(1.99 ± 0.62), (2.38 ± 0.16)μg/L] and Cath-K [(89.07 ± 19.66), (110.16 ± 9.81)pmol/L] in the low-and high-dose fluorosis groups were higher than those in the control group[(0.15 ± 0.03)μg/L,( 18.32 ± 2.27)pmol/L], and the high fluorosis group was obviously higher than the low fluorosis group (all P < 0.05). Each group of serum PI3K and Akt1 protein and mRNA were compared, the difference was statistically significant(F- 178.16,118.08,38.81,52.31, all P< 0.05). Compared to the control group (181.55 ± 4.24,188.46 ± 2.18,3.84 ± 1.69,4.33 ± 0.89), the protein and mRNA expressions of PI3K(171.66 ± 2.85,154.12 ± 4.15,11.31 ± 4.18,20.54 ± 6.68), Akt1(177.47 ± 3.16,156.42 ± 3.18,12.52 ± 3.13,19.43 ± 5.36) were higher in the low- and high-dose fluorosis groups (all P < 0.05), and the high fluorosis group was obviously higher than the low fluorosis group (all P < 0.05). Conclusions BGP and Cath-K contents could be used as bone metabolic indices in the endemic fluorosis disease. Fluoride can increase the expression of PI3K and Akt1 mRNA and protein in bone tissue of fluorosis rats, and PI3K/Akt1 signaling pathway may be involved in the pathogenesis of bone injury caused by fluoride.     

氟中毒大鼠骨组织病理改变动态分析

目的动态观察亚慢性氟中毒大鼠骨组织的超微结构变化，分析亚慢性氟中毒大鼠骨组织病变特征。方法将雄性Wistar大鼠按体质量随机分成2个组，氟化钠组每日饮用含氟150mg／L的氟化钠水溶液，正常对照组饮用自来水，共饲养6个月，每月处死1批大鼠，光镜观察长骨干骺端的病变特点，常规透射电镜观察骨组织中各细胞成分的超微结构病变特点。结果成功地复制出了大鼠氟中毒的模型：随着染氟时间的延长，氟化钠组大鼠的骨小梁密度同对照组相比明显增加。电镜观察中可见氟中毒组大鼠骨细胞变性坏死明显，成骨细胞和破骨细胞都异常活跃，其细胞器结构都有不同程度的损伤：破骨细胞表现为溶酶体数量减少并伴有溶酶体酶的合成减少。结论高剂量氟可以直接对大鼠骨组织中的各种细胞成分造成破坏，并不同程度地促进成骨细胞和破骨细胞的活跃，最终表现为骨转换增强。     

慢性氟中毒对大鼠大脑皮质神经细胞活性氧水平和线粒体融合的影响

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.

Abstract：

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.     

慢性氟中毒对大鼠脑组织Phospho-Elk-1表达的影响

目的 观察慢性氟中毒大鼠脑组织中细胞外调节蛋白激酶(ERK1/2)信号转导通路下游作用底物三元复合物因子Phospho-Elk-1的表达和分布,探讨慢性氟中毒所致学习记忆损害的发生机制.方法 SD 大鼠72只,体质量100～120 g,按体质量随机分为3组,每组24只,雌雄各半.对照组饮用自来水(含氟量<0.5 mg/L),低氟组和高氟组饮用加入氟化钠的自来水(P质量浓度分别为5.0、50.0 mg/L).6个月后,称取大鼠体质量,观察氟斑牙发生情况,用氟离子选择电极法检测大鼠尿氟及骨氟;用Morris水迷宫方法的定向航行实验检测大鼠学习能力,空间探索实验检测大鼠记忆能力;用免疫组织化学方法检测大鼠脑组织中Phospho-Elk-1在蛋白水平的表达和分布.结果 低氟组和高氟组大鼠体质量[(449.2±77.1)、(312.8 ±89.7)g]较对照组[(635.5±76.2)g]显著下降(P均<0.05),出现不同程度氟斑牙(x2=7.83,P<0.05),尿氟[(2.56±0.91)、(5.73±3.14)mg/L]及骨氟[(709.2±37.4)、(1306.3 ±102.4)mg/kg]较对照组[(0.92±0.30)mg/L、(348.5 ±89.2)mg/kg]明显升高(P均<0.05).低氟组和高氟组大鼠逃避潜伏期[(7.4±4.1)、(12.2±5.7)s]较对照组[(4.8±2.7)s]明显延长(P均<0.05),第1次穿越平台区时同[(4.18±1.10)、(5.89±0.56)s]较对照组[(1.17±0.75)s]显著延长(P均<0.05),均以高氟组尤为明显(P均<0.05).低氟组和高氟组大鼠海马CA1区(167.4±8.3、163.2±9.4)、CA2区(175.7±5.0、183.3±4.2)、CA3区(165.2±11.6、162.9±4.4)、CA4 区(168.7±6.9、169.5±5.3)、齿状回(185.2 ±4.0、193.1±6.1)及尾壳核(181.4±3.8、179.8±5.5)神经细胞Phospho-Elk-1表达水平较对照组(142.4±8.1、144.9±8.4、143.6±5.8、116.8±9.1、140.2±7.8、163.1±13.1)显著增加(P均<0.05).结论 慢性氟中毒可引起大鼠脑组织海马及尾壳核区域Pbospho-Elk-1表达水平升高,这种改变可能与大鼠学习记忆能力下降机制有一定关系.

Abstract：

Objective To investigate the expression and distribution of the downstream substrate of extracellular regulated protein kinase(ERK1/2) pathway, ternary complex factor phospho-Elk-1, in rat brains with chronic fluorosis, and reveal the mechanism of the impaired learning and memory ability caused by chronic fluorosis. Methods Seventy-two SD rats, weighing 100 - 120 g, were randomly divided into 3 groups, 24 in each group (half male and half female). The rats in control group were fed with tap water (fluoride < 0.5 mg/L); low- and high-dose fluoride groups were fed with tap water with different concentrations of NaF(5.0,50.0 mg/L F-, respectively). After 6 months, body weight was weighed, dental fluorosis was determined by observation and urinary fluoride and bone fluoride were detected by fluorine ion-selective electrode; the learning ability of rats was measured by navigation test of Morris water maze, and memory ability by spatial probe test in Morris water maze; the expression and distribution of phospho-Elk-1 in different brain regions were detected by immunohistochemistry method. Results In low- and high-fluoride groups, the body weight of rat[(449.2 ± 77.1), (312.8 ± 89.7)g] was significantly decreased than that of control [(635.5 ± 76.2 )g, all P< 0.05], the varying degrees of dental fluorosis were observed(x2 = 7.83, P<0.05), urinary fluoride[(2.56 ±0.91),(5.73 ±3.14)mg/L] and bone fluoride[(709.2 ± 37.4) ,(1306.3 ± 102.4) mg/kg] were significantly higher than those in controls[(0.92 ± 0.30)mg/L,(348.5 ± 89.2)mg/kg, all P< 0.05]. The escape latency of low- and high-fluoride groups[ (7.4 ± 4.1), (12.2 ± 5.7)s] was longer than that of control [(4.8 ± 2.7 )s, all P < 0.05] and the escape latency in high-fluoride group was significantly longer than that in other groups (all P < 0.05); in spatial probe test, the time of first crossing platform was longer in rats with fluorosis [(4.18 ± 1.10),(5.89 ± 0.56)s] as compared to control[(1.17 ± 0.75)s, all P< 0.05]. Expressions of phospho-Elk-1 in the hippocampus CA1(167.4 ± 8.3,163.2 ± 9.4), CA2(175.7 ± 5.0,183.3 ± 4.2), CA3(165.2 ± 11.6,162.9 ± 4.4), CA4(168.7± 6.9,169.5 ±5.3), fascia dentate (185.2 ±4.0,193.1 ±6.1) and caudate putamen( 181.4 ± 3.8, 179.8 ± 5.5) in low- and high-fluoride groups were higher than those of controls(142.4 ± 8.1,144.9 ± 8.4,143.6 ± 5.8, 116.8 ± 9.1,140.2 ± 7.8,163.1 ± 13.1, all P< 0.05). Conclusion Chronic fluorosis can cause increased expression of phospho-Elk-1 in the hippocampus and caudate putamen region of rat brains, which might be related to the mechanisms of decreased learning and memory ability of rats overexposed to fluoride.     

氟中毒大鼠骨组织中内质网应激实验研究

目的 观察内质网应激在氟中毒大鼠骨组织中的变化,探索内质网应激在氟骨症发病机制中的可能作用.方法 48只Wistar大鼠,按体质量分成4组,每组12只.对照组和低钙组分别饲以常食饲料(含钙量为0.790%)和自制低钙饲料(含钙量为0.063%),饮用自来水(含NaF＜1 mg/L);高氟组和低钙高氟组分别饲以常食饲料和自制低钙饲料,饮用加氟(NaF,221 mg/L)自来水.实验期间动物自由进食、进水,每周测体质量1次.实验期3个月.生化方法检测大鼠血清氧化应激酶、尿酸(URIC)和碱性磷酸酶(ALP)活性.抽提大鼠一侧股骨骨干的总RNA,利用RT-PCR技术分析内质网应激相关基因BIP、Xbp1、CHOP和PDI的表达水平.结果 低钙高氟组血清丙二醛(MDA)水平高于对照组[(14.74±3.11)μmol/L比(10.15±1.96)μmol/L,P＜0.05];高氟组血清谷胱甘肽过氧化物酶(GPx)的活性高于对照组[(3.87±0.41)×103 U/L比(2.85±0.55)×103U/L,P＜0.05];高氟组和低钙高氟组的尿酸(URIC)分别低于对照组和低钙组[(73.95±9.52)μmol/L比(110.43±25.48)μmol/L,(54.32±22.09)μmol/L比(101.71±17.01)μmol/L/L,P＜0.05].低钙高氟组大鼠的ALP活性高于对照组[(24.77±4.57)×103 U/L比(12.91±3.97)×103 U/L,P＜0.01)].低钙组和低钙高氟组BIP/GAPDH的表达高于对照组(1.38±0.24、1.35±0.12比1.14±0.06,P＜0.05).低钙高氟组的Xbp1/GAPDH的表达高于对照组和低钙组(1.48±0.20比1.02±0.25、1.07±0.25,P＜0.01);低钙高氟组的CHOP/GAPDH的表达高于对照组(0.84±0.18比0.52±0.07,P＜0.05).结论 氟中毒大鼠机体内氧化应激态和骨形成有明显的增强,并伴有骨组织细胞的内质网应激.说明内质网应激与氧化应激很可能都参与了氟骨症的发病机制.     

亚慢性氟中毒对大鼠骨组织诱导型一氧化氮合酶表达的影响

目的 动态观察亚慢性氟中毒大鼠骨组织中诱导型一氧化氮合酶(iNOS)的表达变化,分析亚慢性氟中毒骨组织中一氧化氮(NO)自由基损伤机制.方法 将雄性Wistar大鼠按体质量随机分成两组.氟化钠组每日饮用含氟150mg/L的水溶液,对照组饮用自来水,共饲养24周,每4周处死一批动物,测定大鼠血清及骨组织中的含氟量,Griess Reagent法检血清NO,RT-PCR法和免疫组化法检测骨组织中iNOSmRNA及蛋白表达.结果 氟化钠组血清NO波动较大,第8周时[(19.94±3.04)nmol/L]明显高于对照组[(9.11±1.21)nmol/L].差异有统计学意义(t=9.36,P＜0.01),而第20、24周时[(11.55±3.54)、(20.83±2.49)nmol/L]明显低于对照组[(31.13±3.93)、(33.10±7.37)nmol/L],两组比较差异均有统计学意义(t值分别为10.47、4.46,P＜0.01):第4、8、12、16、20、24周时氟化钠组[(1.87±0.11)、(1.87±0.78)、(1.90±0.29)、(1.93±0.67)、(1.88±0.38)、(1.84±0.03)]骨组织iNOS mRNA表达均明显高于对照组[(0.41±0.25)、(0.30±0.17)、(0.18±0.06)、(0.63±0.15)、(0.66±0.04)、(0.65±0.55)],两组比较差异均有统计学意义(t值分别为13.09、4.82、14.23、4.64、7.82、5.29.P＜0.01).iNOS蛋白主要表达在干骺端肥大区软骨细胞、关节软骨的深层软骨细胞、成骨细胞和韧带细胞中.结论 高剂量氟可以持续诱导iNOS表达,催化NO合成,通过局部调节成骨细胞和破骨细胞活性参与氟中毒骨转换过程.     

硒对饮茶型氟中毒大鼠抗氟能力的影响和骨保护作用

目的探讨硒对饮茶型氟中毒鼠抗氟能力和骨的保护作用。方法将雄性Wistar大鼠按体质量随机分成6组:对照组、氟化钠组、茶氟组、高硒对照组、高硒氟化钠组和高硒茶氟组。对照组饮用自来水,氟化钠组饮用含氟100mg/L自来水,茶氟组饮用含氟100mg/L的砖茶浸出液,高硒组在饲料中加硒2.97mg/kg。3个月后处死实验动物,测定全血谷胱甘肽过氧化物酶(GSH-Px)活力,分离血清测定血氟,检测氟斑牙发生情况,取股骨干骺端进行骨小梁面密度分析。结果高硒氟化钠组血氟同氟化钠组比较明显降低(t=2.12,P<0.05),有统计学意义,同茶氟组比较无统计学意义。茶氟组和氟化钠组不论是否加硒,两组间氟斑牙和骨小梁面密度比较,差异无统计学意义。结论高硒可以降低氟化钠组大鼠的血氟浓度,但不能明显减轻大鼠氟中毒的病理损伤。     

安替氟对高骨氟负荷大鼠的降氟解毒作用

为研究安替氟是否对高骨氟负荷大鼠具有明显的降氟解毒作用，给幼龄大鼠饮高氟水（含氟５０ｍｇ／Ｌ）８周后停止给氟，同时在饮水中添加安替氟（６ｇ／Ｌ），连续４周。结果表明，安替氟可使氟致肾小管上皮细胞损伤修复以及骨、牙氟负荷下降过程加速，尿氟排出也呈增加趋势，但其机理尚不清楚。     

燃煤污染型氟中毒大鼠肾组织中PURA基因及其蛋白的表达

目的 探讨PURA基因及其蛋白在燃煤污染型氟中毒大鼠肾组织中的表达情况.方法 SD大鼠36只,体质量80-100 g.将大鼠按体质量随机分对照组、加氟组、高氟组,每组12只,雌雄各半.对照组、加氟组和高氟组大鼠分别饲以含氟量为1.5、25.0、60.0 ms/ks的饲料.4个月后,采用RT-PCR技术及免疫组化技术检测大鼠肾组织PURA基因及其蛋白表达水平.结果 加氟组和高氟组大鼠肾组织PIJRA mRNA[(2.74±1.06)、(4.29±2.11)]及蛋白表达[(28 827.91±4801.94)、(61 146.96±4997.55)]均高于对照组[(1.13±0.87)、(7131.95±1524.54),P均<0.05)],高氟组大鼠肾组织PURA mRNA及蛋白表达高于低氟组(P均<0.05).结论 高氟可以导致大鼠肾组织PURA mRNA及蛋白表达水平增强.