亚慢性氟暴露致小鼠海马损伤的影响及分子机制研究  

Effects of subchronic exposure to fluorine on hippocampal injury in mice and its molecular mechanism

作　　者：年未未 汪晓宇 邵丹丹 于秋丽 欧阳玮[2] 章子贵[3] 阮琴[3] NIAN Weiwei;WANG Xiaoyu;SHAO Dandan;YU Qiuli;OUYANG Wei;ZHANG Zigui;RUAN Qin(College of Chemistry and Life Seienee,Zhejiang Normal University,Jinhua 321004;College of Sports and Health Science,Zhejiang Normal University,Jinhua 321004;College of Xing Zhi,Zhejiang Normal University,Jinhua 321004)

机构地区：[1]浙江师范大学化学与生命科学学院,金华321004 [2]浙江师范大学体育与健康科学学院,金华321004 [3]浙江师范大学行知学院,金华321004

出　　处：《环境科学学报》2018年第11期4512-4519,共8页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.81573101)~~

摘　　要：为探明亚慢性氟中毒致小鼠海马损伤及分子机制,选用ICR雄性小鼠140只,随机分为对照(C)、低氟(LF)、高氟(HF)、低氟(LF)+L钙离子通道激动剂(FPL)、低氟(LF)+L钙离子通道抑制剂(NIF)、高氟(HF)+激动剂(FPL)、高氟(HF)+抑制剂(NIF) 7组,分别饮用自来水、5、30 mg·L^(-1)氟化钠水溶液90 d,氟染毒第84 d分别腹腔注射生理盐水、FPL64176、Nifedipine7d.同时,采用开场行为及水迷宫检测学习记忆能力;通过HE切片染色观察海马形态结构;根据试剂盒说明检测脑组织谷胱甘肽过氧化物酶(GSH-PX)、总超氧化物歧化酶(SOD)酶活性及丙二醛(MDA)含量;利用RT-PCR和Western Blot法分别检测海马内凋亡相关分子CaMKⅡ和Bax、Bcl-2基因/蛋白表达.结果发现,HF组、LF+FPL组和HF+FPL组小鼠毛发粗糙,暴躁不安.LF、HF组小鼠自发活动、探究行为及空间学习记忆力显著下降(p<0.05),海马细胞损伤,SOD、GSH-PX活性极显著下降(p<0.01),CaMKⅡ基因/蛋白表达水平显著(p<0.05)或极显著(p<0.01)上调,Bax基因/蛋白表达水平显著(p<0.05)或极显著(p<0.01)上调,Bcl-2基因/蛋白表达水平显著(p<0.05)或极显著(p<0.01)下调,Bax与Bcl-2基因/蛋白表达水平比值显著(p<0.05)或极显著(p<0.01)上调;LF+FPL、HF+FPL处理加剧了上述基因/蛋白表达水平,LF+NIF、HF+NIF组可逆转上述基因/蛋白表达水平.结果提示,氟中毒致脑损伤与L型钙离子通道及下游相关分子表达异常密切相关,而L钙离子通道抑制剂(Nifedipine)能改善氟暴露造成的海马损伤.To study the hippocampus damage mechanism following subchronic fluorosis exposure in mice. 140 ICR male mice were randomly fed with free drinking tap water containing less than 0.5 mg· L-1 （ control）, 5 mg· L- 1 （ LF）, and 30 mg· L-1 （ HF ） fluoride （NaF） for 90 days. At day 84 following exposure to fluorine; the mice were treated with FPL64176 （LF＋FPL, HF＋FPL） or nifedipine （LF＋NIF, HF＋NIF） ip. The open field and the water maze were used to detect learning and memory, and hippocampal morphological structure was observed. Glutathione peroxidase （GSH-PX）, total superoxide dismutase （SOD） enzyme activity, and malondialdehyde （MDA） in brain tissue were detected according to kit instructions. RT-PCR and Western blot were separately used to detect CaMKII, Bax and Bcl-2 Genes/protein in the hippocampus. Mice in group HF, group LF＋FPL and group HF＋ FPL had rough, irritable hair. Spontaneous activity, inquiried spatial learning and memory decreased significantly in mice of low fluorine group and high fluoride group compared to the control group （p 〈 0.05 ）. The injuried hippocampal cell, the decreased activity of GSH-PX （p 〈 0.01 ）, up-regulated expression levels of CaMKII （p〈0.05） and Bax （p〈0.05 or p〈0.01 ）, down-regulated Bcl-2 （p〈0.05 or p〈0.01 ） gene/preteinthe, and the increased ratio of Bax and Bcl-2 （p〈0.05 or p〈0.01 ） were found. FPL64176 aggravated and nifedipine reversed these changes induced by fluorine exposure. The brain injury induced by fluoride exposure is closely related to L-type calcium channel and downstream signal, and block of L-type calcium channel can improve the hippocampal damage caused by fluorine exposure.

关 键 词：氟中毒 Morris水迷宫 脑海马 组织结构 部分氧化及抗氧化酶 Bax Bcl-2 CaMKⅡ 

分 类 号：X171.5[环境科学与工程—环境科学]