摘要目的:本研究旨在探索铅染毒是否会导致斑马鱼焦虑的发生，并对其机制进行初步探索。方法:于2020年5月，收集受精后4 h（4hpf）的斑马鱼胚胎，以E3培养液作为对照组，不同的铅染毒浓度（6、12、24、48 μmol/L）作为染毒组，染毒时间为140 h。计算144 hpf斑马鱼的胚胎死亡率、胚胎孵化率和幼鱼畸形率；观察144 hpf幼鱼的行为学变化（运动速度、移动距离、活跃度、绝对转角、光照惊恐反应、黑暗逃避反应和趋触性）。并且检测斑马鱼幼鱼头部的活性氧（ROS）、丙二醛（MDA）水平。用ELISA试剂盒检测与焦虑相关的神经递质5-羟色胺（5-HT）、多巴胺（DA）、去甲肾上腺素（NA）和促肾上腺皮质激素释放激素（CRH）的表达量。结果:12、24和48 μmol/L铅染毒组斑马鱼胚胎死亡率高于对照组，胚胎孵化率低于对照组，24和48 μmol/L铅染毒组斑马鱼幼鱼畸形率高于对照组（ P<0.01）；24和48 μmol/L铅染毒组幼鱼运动速度、活跃度和趋触性低于对照组，绝对转角高于对照组，48 μmol/L铅染毒组幼鱼移动距离和黑暗逃避反应低于对照组，12、24和48 μmol/L铅染毒组幼鱼的光照惊恐反应低于对照组（ P<0.05）。24和48 μmol/L铅染毒组幼鱼头部ROS水平和MDA浓度高于对照组（ P<0.05）；12、24和48 μmol/L铅染毒组幼鱼头部NA和DA的含量低于对照组，24和48 μmol/L铅染毒组幼鱼头部5-HT和CRH浓度高于对照组（ P<0.05）。 结论:铅对斑马鱼有一定的胚胎发育毒性，且可导致斑马鱼发生焦虑样神经行为、神经递质改变以及氧化应激的发生。

abstractsObjective:This study aims to explore whether lead exposure could cause anxiety of zebrafish larvae, and to explore its mechanism.Methods:In May 2020, zebrafish embryos 4 hours after fertilization (4 hpf) were collected, E3 culture medium was used as the control group, and different lead exposure concentrations (6, 12, 24, 48 μmol/L) as the poisoned group during the time was 140 h. The mortalities, hatching rates and deformity rates were calculated, the behavioral changes of 144 hpf larvae were observed (moving speed, moving distance, activity, absolute turn angle, the light-evoked startle response, darkness-evoked escape response and thigmotaxis) . The levels of reactive oxygen species (ROS) and malondialdehyde (MDA) were detected in zebrafish larvae in the heads. ELISA kits were used to detect the expression of 5-hydroxytryptamine (5-HT) , dopamine (DA) , noradrenaline (NA) and corticotropin-releasing hormone (CRH) related to anxiety.Results:The mortalities rates of zebrafish embryos in the lead exposure concentration of 12, 24 and 48 μmol/L were higher than the control group, and the embryo hatching rates were lower than control group. The deformity rates of zebrafish larvae in the lead exposure concentration of 24 and 48 μmol/L were higher than control group ( P<0.01) . The movement speed, activity and thigmotaxis of zebrafish larvae in the lead exposure concentration of 24 and 48 μmol/L were significantly lower than control group, the absolute turn angle were higher than control group ( P<0.01) . The moving distance and darkness-evoked escape response of zebrafish larvae in the lead exposure concentration of 48 μmol/L group were lower than control group ( P<0.05) . The light-evoked startle response of zebrafish larvae in the lead exposure concentration of 12, 24 and 48 μmol/L groups were lower than control group ( P<0.05) . The ROS levels and MDA concentrations in the heads of larvae in the lead exposure concentration of 24 and 48 μmol/L were higher than control group ( P<0.05) . The levels of NA and DA in the heads of the larvae in the lead exposure groups of 12, 24 and 48 μmol/L were lower than control group, and the levels of 5-HT and CRH in the heads of the larvae in the lead exposure groups of 24 and 48 μmol/L were higher than control group ( P<0.05) . Conclusion:Lead exposure is toxic to zebrafish embryonic development and may cause anxiety-like neurobehavior changes and oxidative stress in zebrafish.