非洲爪蟾胚胎用于发育神经毒性测试的方法

An assay for testing developmental neurotoxicity of chemicals using Xenopus laevis embryos

在美国材料与测试协会(ASTM)的非洲爪蟾胚胎致畸试验(FETAX)的基础上,以已知具有发育神经毒性的氯化甲基汞为模式化合物,探索一种以体征、运动神经元形态和运动行为参数为终点指标的研究发育神经毒性的方法.非洲爪蟾胚胎暴露氯化甲基汞3 d时,观察到暴露组胚胎的运动能力随暴露浓度(100—400 nmol·L-1)的增加而减弱.暴露4 d发现300 nmol·L-1和400 nmol·L-1暴露组胚胎体长和运动神经元明显短于对照组.暴露持续7 d,通过行为分析软件对蝌蚪运动行为定量,发现暴露处理的蝌蚪的游泳速率明显小于对照组.以上结果显示,非洲爪蟾胚胎可用来研究化学品的发育神经毒性,胚胎的体征、运动神经元形态和运动行为可以作为相对敏感的评价指标.

Based on Frog Embryo Teratogenesis Assay-Xenopus（ FETAX） of American Society for Testing and Materials,we aimed to establish an assay for evaluating developmental neurotoxicity of chemicals using body features, motoneuronal morphology and motor behavior as endpoints.Methylmercury chloride（ CH3HgCl） was used as a model compound for developmental neurotoxicity. Following 3 d-exposure,the embryos exhibited weaker motor ability with increases in CH3 HgCl concentrations. After 4 d-exposure to CH3 HgCl,the embryos appeared shorter body lengths and motoneurons in 300 nmol·L^-1and 400 nmol·L^-1groups compared with the control.Seven day-exposure to CH3 HgCl resulted in a decrease in the swimming velocity of the tadpoles in a concentration-dependent manner. In conclusion,our results show that X. laevis embryos can be used to investigate developmental neurotoxicity of chemicals,and body features,motoneuronal morphology and motor behavior are sensitive endpoints.