慢性氟中毒对大鼠脑组织蛋白激酶Cβ／衔接蛋白通路的影响

Influence of chronic fluorosis on protein kinase Cβ/p66shc signal pathway in the brain of rats

目的观察慢性氟中毒对大鼠脑组织中蛋白激酶cp（proteinkinasecB，PKC[5）／衔接蛋白（p66she）信号通路的影响，探讨氟中毒脑损伤机制。方法SD大鼠30只，按体质量采用随机数字表法分为对照组（饮水氟含量〈0．5mg／L）、低氟组（饮水氟含量为10．0mg／L）、高氟组（饮水氟含量为50．0mg／L），每组10只，雌雄各半，实验期6个月。用蛋白印迹法检测大鼠脑组织中PKCt3、脯氨酰异构酶（Pinl）、p66shc、磷酸化p66shc（phospho—p66shc）蛋白表达；用免疫组织化学方法检测大鼠脑组织中神经元核抗原（NeuN）、p66shc、phospho．p66shc蛋白表达。结果蛋白印迹法检测结果：高氟组大鼠脑组织中PKCl5、phospho—p66she、Pinl蛋白表达[（193．00±57．53）％、（228．21±71．14）％、（201．54±50．86）％]高于对照组[（100．00±21．24）％、（100．00±40．55）％、（100．00±13．35）％，P均〈0．05]。免疫组织化学方法检测结果：高氟组及低氟组大鼠脑组织NeuN蛋白表达[（49．50±12．57）％、（65．66±14．58）％]低于对照组[（100．00±18．32）％，P均〈0．01]，高氟组phospho—p66shc蛋白表达[（242．66±93．01）％]高于低氟组及对照组[（152．53±60．65）％、（100．00±25．63）％，P均〈0．01]，p66shc表达组间比较差异无统计学意义（F=1.01，P〉0．05）。结论慢性氟中毒导致脑组织中PKCβ、Pinl、phospho-p66shc蛋白表达水平升高，可能与慢性氟中毒脑损伤的机制有关。

Objective To investigate the influence of chronic fluorosis on protein kinase Cβ（PKCI3）/ p66shc signal pathway in the brain of rats, and reveal the molecular mechanism of brain damage. Methods According to body weight by the random number table method thirty SD rats were divided into three groups of 10 each （half females and half males）, the normal control group [less than 0.5 mg/L of fluorine （prepared with NaF） in drinking water], low fluoride exposure group （10.0 mg/L fluorine）, and high fluoride exposure group （50.0 mg/L fluoride）. The experiment period was 6 months. The protein level of PKCβ, p66shc, phospho-p66shc and preserved ammonia acyl isomerase （Pinl） in rat brain was detected by Western blotting. The level of neuron nuclear antigen （NeuN）, p66shc and phospho-p66sh in brain of rats was detected by immunohistochemistry. Results By Western blotting, the levels of PKCβ, Pinl and phospho-p66shc protein in brain tissue in high fluoride exposure group [（193.00 ± 57.53）%, （228.21 ± 71.14）%, （201.54 ± 50.86）%] were higher than those of the normal control groups [（100.00 ± 21.24）%, （100.00 ±40.55）%, （100.00 ± 13.35）%, all P 〈 0.05]. By immunohistochemistry, the numbers of NeuN staining in brain tissue of the rats in both high and low fluoride exposure groups [（49.50± 12.57）%, （65.66 ± 14.58）%] were lower than that of the control group [（100.00 ±18.32）%, all P 〈 0.01]. The level of phospho-p66shc protein in brain tissue in high fluoride exposure group [（242.66 ± 93.01）%] was higher than those of the low fluoride exposure and the normal control groups [（152.53 ± 60.65）%, （100.00 ± 25.63）%, all P 〈 0.01]. Conclusion Chronicfluorosis has increased the expressions of PKCβ, Pin1 and phospho-p66shc at protein level in brain of rats, which may be related to the molecular mechanism of brain damage resulted from chronic fluorosis.