纳米二氧化钛经气管染毒对大鼠肝、肾的影响

Effects of Transbronchial TiO_2 Nanoparticles Poisoning on Liver and Kidney in Rats

背景与目的:探讨纳米二氧化钛(nano-TiO2,粒径50nm)经气管染毒对大鼠肝、肾的影响。材料与方法:选取24只SD大鼠,随机分为0.5、5.0、50.0mg/kgnano-TiO2组和对照组(0.15%氯化钠溶液)。经气管注入nano-TiO2(或NaCl溶液)染毒7d后处死,取股动脉血检测血常规及生化指标;计算肝、肾脏器系数;测定血浆、肝脏和肾脏的超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)活力和丙二醛(MDA)含量;并进行组织病理学检查。结果:血常规、血生化和脏器系数各项检测指标染毒组与对照组比较差异均无统计学意义(P>0.05)。5.0、50.0mg/kgnano-TiO2染毒组大鼠肾脏组织SOD活力与对照组相比明显降低(P<0.05),50.0mg/kgnano-TiO2染毒组大鼠血浆及肾脏组织GSH-PX活力与对照组相比明显降低(P<0.05),0.5、5.0mg/kgnano-TiO2染毒组大鼠肝脏组织MDA含量与对照组相比明显升高(P<0.05),而肝、肾组织未产生明显组织病理学改变。结论:经气管急性染毒后,nano-TiO2可引起肝、肾组织氧化应激作用,但未见肝肾功能及病理学损伤,其生物和毒理学意义有待进一步研究。

BACKGROUND AND AIM：To explore the effects of transbronchial TiO2 nanoparticles（size 50 nm）poisoning on liver and kidney in rats.MATERIALS AND METHODS：24 SD rats were randomly divided into 0.5,5.0 and 50.0 mg/kg nano-TiO2 groups and control group（0.15% sodium chloride solution）.Rats were treated with intratracheal TiO2 nanoparticle suspension and were sacrificed after 7 days.Complete blood count and biochemical indexes and tissue coefficients were assessed.The activities of superoxide dismutase（SOD）and glutathione peroxidase（GSH-PX）and the contents of maleic dialdehyde（MDA）in plasma,liver and kidney were measured.Pathological changes of liver and kidney were also examined.RESULTS：Indexes of blood count,blood biochemistry and tissue coefficients did not show statistical significance between nano-TiO2 exposure groups and control group.Kidney SOD activities of 5.0 and 50.0 mg/kg nano-TiO2 groups were obviously decreased compared with that in control group（P〈0.05）.GSH-PX activities in plasma and kidney of 50.0 mg/kg nano-TiO2 group were lower than that in control group（P〈0.05）.In liver,MDA contents of 0.5 and 5.0 mg/kg nano-TiO2 groups were significantly increased compared to the control group（P〈0.05）.No obvious pathological changes of liver and kidney was observed.CONCLUSION：Acute transbronchial exposure to TiO2 nanopaticles could induce oxidative stress in the liver and kidney,but did not influence hepatic or renal functions nor cause pathological changes.Its biological and toxicological significance needs further studies.