中文摘要：

本文旨在运用半定量RT-PCR技术,研究不同浓度及不同时间镉胁迫下,涡虫（Dugesia japonica）体内Dj Hsp70及Dj P53基因的表达规律。提取相同暴露时间（48 h）不同浓度（0,20滋g/L,40滋g/L,80滋g/L,160滋g/L,320滋g/L）及相同暴露浓度（25滋g/L）不同暴露时间（0,1 d,3 d,6 d,9 d,15 d）镉胁迫下涡虫组织总RNA,反转录得到cD NA,以茁-actin作为内参,应用半定量RT-PCR方法,检测Dj Hsp70及Dj P53基因的表达量。结果表明：与对照相比,重金属镉胁迫导致涡虫体内Dj Hsp70、Dj P53基因表达量均上调,存在明显的＂毒理兴奋＂作用。在25滋g/L镉离子处理15 d后Dj Hsp70基因表达呈现下降趋势。因此,半定量RT-PCR方法应用于淡水生态环境镉污染评价具有较大的潜力。

英文摘要：

The objective was to explore the expression pattern of Dj Hsp70 and Dj P53 gene in planarian（Dugesia japonica） using semi-quantitative RT-PCR technology stressed with cadmium.Total RNAs were extracted respec-tively from planarian exposed to cadmium at 0,20 μg/L,40 μg/L,80 μg/L,160 μg/L,320 μg/L for 48 h and 25 μg/L for 1 d,3 d,6 d,9 d and 15 d,and c DNA were reversely transcribed.Expression quantities of Dj Hsp70 and Dj P53 gene in the different groups were detected by optimized by Semi-quantitative RT-PCR method and β-actin is used as house-keeping gene.The results showed cadmium stress had certain inducing effect to gene expression,and had a toxicology excited effects.Expression quantities of Dj Hsp70 and Dj P53 gene after cadmium stresses were all up regulation compared with contrasts.However,the expression quantities of Dj Hsp70 showed a decreasing tendency with the 25 μg/L for 15 d.Thus,applying RT-PCR has potential application in the evaluation of cadmium pollution upon freshwater environment.Keywords