氯化甲基汞对秀丽隐杆线虫运动和感觉功能的影响

Effects of methylmercury chloride on motor and sensory function of Caenorhabditis elegans

目的分析神经毒物氯化甲基汞对模式生物秀丽隐杆线虫运动和感觉行为的影响,初步探讨利用秀丽隐杆线虫研究氯化甲基汞神经毒性的可能性。方法采用氯化甲基汞对L1期、L4期幼虫分别急性（30 min）染毒[终浓度分别为0（溶剂对照）~202.5μmol/L和0~1 200μmol/L]和慢性（24 h）染毒[终浓度分别为0（溶剂对照）~80μmol/L和0~150μmol/L]。测定半数致死浓度（LC50）及行为学指标。结果氯化甲基汞致L1期、L4期秀丽隐杆线虫的LC50（30 min）分别为（65.93±8.89）μmol/L和（206.71±35.43）μmol/L,LC50（24 h）分别为（11.59±0.79）μmol/L和（24.89±4.88）μmol/L,L1期秀丽隐杆线虫对氯化甲基汞的毒性较L4期敏感。随着氯化甲基汞暴露剂量的升高,急性和慢性染毒L1期、L4期秀丽隐杆线虫的弯曲频率和头部摆动频率均呈下降的趋势,基本运动能力呈减弱趋势,触碰反应呈迟钝的趋势。结论氯化甲基汞可抑制运动和感觉功能,秀丽隐杆线虫可用于氯化甲基汞神经毒性的研究。

Objective To know the methylmercury chloride induced neurotoxicity by using Caenorhabditis elegans（C.elegans） as the model animal and assess the effects of methylmercury chloride on motor and sensory function of C.elegans. Methods C.elegans L1 larvae and L4 larvae were respectively acutely（30 min） exposed to methylmercury chloride [final concentrations of 0（solvent control）-202.5 μmol/L and 0-1 200 μmol/L] and chronically（24 h） exposed to methylmercury chloride [final concentrations of 0（solvent control）-80 μmol/L and 0-150 μmol/L].Then the median lethal concentration（LC50） and behavioral changes were measured. Results After exposure to methylmercury chloride, the LC50（30 min） values of C.elegans L1 and L4 larvae were（65.93±8.89） μmol/L and（206.71±35.43） μmol/L respectively, the values of LC50（24 h） for L1 and L4 larvae were（11.59±0.79） μmol/L and（24.89±4.88） μmol/L respectively, L1 larvae are more sensitive than L4 larvae. With increasing doses of methylmercury chloride, body bends and head thrashes were lower, basic movements were weaken and touch-response was obtuse after acute and chronic methylmercury chloride exposure to C.elegans L1 and L4 larvae. Conclusion Methylmercury chloride could inhibit the motor and sensory function. C.elegans can be used as a model for neurotoxicity study of methylmercury chloride.