燃煤来源型过量氟对大鼠氧化应激的影响

The effects of oxidative stress on the rats with dental fluorosis caused by coal burning

目的探讨氧化应激在燃煤来源型氟斑牙发生中的作用。方法以高氟煤拌粘土为燃料,每天生火10 h构建高氟空气模型,取病区煤烘玉米,配制不同比例饲料喂养大鼠。复制燃煤来源型氟斑牙大鼠模型。30只SD大鼠,体重均等、雌雄各半随机分为五组:高氟空气加饲料氟含量40 mg/kg组(H组)、高氟空气加饲料氟含量25 mg/kg组(M组)、高氟空气加饲料氟含量10 mg/kg组(L组)、高氟空气加普食组(A组)及阴性对照组(C组)。饲养16周后处死大鼠,测肝、肾组织及血清中丙二醛(MDA)含量、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物(GSH-Px)活性。结果成功复制出大鼠氟斑牙(H、M组全部,L组1只);随染氟剂量的增大,差异均有统计学意义(P<0.01或P<0.05)。H、M、L组大鼠肝、血清MDA含量逐渐升高,肝、肾及血清SOD、CAT活性呈下降趋势,A组肝、肾组织仅SOD活性降低,与C组相比,GSH-Px活性变化无统计学意义。结论高氟空气可能会导致大鼠体内氧化系统与抗氧化系统的异常,在燃煤来源型氟斑牙发生过程中,空气过量氟引起的肝、肾组织氧化应激损伤可能早于其对牙体硬组织的损害,氧化应激可能是氟中毒致机体损伤和氟斑牙发生的重要机制之一。

Objective To learn the effects of oxidative stress on the rat with dental fluorosis caused by coal burning. Methods High fluoride（ F-） air modle was established by burning the fuel,clay rich of F-mixed with coal for 10 h a day. Rats were fed with drying corn with different proportions. Thirty SD rats were randomly divided into 5 groups： the high F-air and fed F-40 mg / kg group（ H）,the high F-air and fed F-25 mg / kg group（ M）,the high F-air and fed F-10 mg / kg group（ L）,the high F-air and common food group（ A） and the control group（ C）. All rats were killed at the end of 16 th week,and then the activities of SOD,CAT,GSH and MDA levels were measured with their reagent boxes respectively. Results The dental fluorosis in rats was replicated successfully. The MDA levels of the experimental groups increased,while SOD and CAT activities decreased（ P〈0. 01 or P〈0. 05）. No statistically considerable difference was found in GSH level）. SOD activities of liver and kidney decreased only in group A（ P〈0. 05）. Conclusions The balance of oxidative and anti-oxidative system may be broken in the rats because of the high F-air. In the occurrence process of coal-burning source dental fluorosis,the oxidative stress of liver and kidney tissue may be earlier than the dental hard-tissue damage caused by high F-air. Oxidative stress may be an important mechanism for body damage and the occurrence of dental fluorosis.