氯化甲基汞和硒代蛋氨酸联合暴露对大鼠体内汞的蓄积和毒性影响

Impact of Co-exposure to Methylmercuric Chloride and Selenomethionine on Mercury Accumulation and Toxicity in Rats

本研究旨在通过用氯化甲基汞和硒代蛋氨酸对大鼠进行暴露,为进一步研究汞和硒在生物体内的蓄积作用及其在体内的生物转运机制提供重要支持。冷原子荧光光谱法(cold atomic fluorescence spectrometry,CVAFS)检测大鼠汞含量;氢化物发生原子荧光光谱法(hydride occurrence by atomic fluorescence spectroscopy,HG-AFS)检测大鼠硒含量;苏木素-伊红(hematoxylin-eosin,HE)染色观察组织形态;单因素方差分析(One-way ANOVA)和Bonferroni法分析大鼠中汞和硒分布的差异性,采用独立样本T检验(independent sample T-test)分析各组之间肝肾功能的差异性。结果显示,不同性别之间雄鼠的汞和硒蓄积量高于雌鼠,相同性别内大鼠对汞和硒的蓄积量大小为肾脏>肝脏>脑>毛发≈粪便,且随着时间的变化汞蓄积量逐渐增加,硒暴露组大鼠肝、肾、脑中硒的蓄积量在30~60 d内随暴露时间的延长持续增加,而到90 d时出现了回落的现象;硒汞联合暴露组中相同汞暴露情况下,随着硒暴露剂量增加各组织汞蓄积量也增加;补硒后,汞和硒蓄积量都有所增加,但汞蓄积量低于单汞组;从生化指标和病理观察看,与对照组相比,单汞组和中硒高汞组的大鼠组织损害程度较为严重,单硒组损害程度最轻。综上所述,硒汞的相互作用会影响在组织中汞和硒的蓄积分布,硒共暴露以及补硒能促进各组织对汞的吸收,其结果受硒汞暴露量和补硒浓度的影响;汞和硒蓄积量能影响大鼠各组织病理改变程度以及肝肾功能,汞蓄积量越高对组织的损害程度越高。

The aim of this study is to provide important support for further research on the accumulation and transport mechanisms of mercury and selenium in vivo by exposing rats to methylmercury chloride and selenomethionine.Cold atomic fluorescence spectroscopy(CVAFS)was used to detect the mercury content in rats;hydride o ccurrence by atomic fluorescence spectroscopy(HG-AFS)was used to detect the selenium content in rats;h ematoxylin-eosi n(HE)staining was used to observe tissue morphology;One-way ANOVA and Bonferroni m ethods were used to a nalyze the differences in mercury and selenium distribution in rats,and Independent sample T-test was used to a nalyze the differences in liver and kidney function between groups.The results showed that the accumulation of mercury and selenium in male mice was higher than that in female mice of different genders,and the accumulation of mercury and selenium in rats of the same gender was in the order of kidney>liver>brain>hair≈feces,and the accumulation of mercury gradually increased with time.The accumulation of selenium in the liver,kidney,and brain of rats exposed to selenium continued to increase with the extension of exposure time from 30 to 60 d,and a phenomenon of decline appeared at 90 d;in the combined selenium and mercury combined exposure group,under the same mercury exposure conditions,the mercury accumulation in each tissue also increased with the increase of selenium exposure dose;after selenium supplementation,both mercury and selenium accumulation increased,but the mercury accumulation was lower than that of the single mercury group;from biochemical i ndicators and p athological observations,compared with the control group,the single mercury group and the m edium selenium high mercury group had more severe tissue damage in rats,while the single selenium group had the lowest degree of damage.In summary,the interaction between selenium and mercury can affect the accumulation and distribution of mercury and selenium in tissues.Co exposure to selenium or supplementation with selenium can promote the a bsorption of mercury in various tissues,and the results are influenced by the exposure level and s upplementation concentration of selenium and mercury.The accumulation of mercury and selenium can affect the degree of p athological changes in various tissues and liver and kidney function in rats.The higher the accumulation of m ercury,the greater the degree of tissue damage.