氯乙酸类饮水氯化消毒副产物对大鼠p53基因的损伤作用研究

Study on rat's DNA damage of p53 induced by chlorinated acetic acids of drinking water disinfection by-products

目的检测二氯乙酸和三氯乙酸对大鼠p53基因的DNA损伤作用,证实其遗传毒性并探讨其致癌作用的分子机制。方法将二氯乙酸、三氯乙酸腹腔注射染毒SD大鼠,提取肝组织DNA,应用依赖随机化末端连接物PCR技术检测其对大鼠p53基因外显子7的DNA损伤作用。结果在DCA染毒组检测出2条杂交条带,表明DCA可引起大鼠肝组织p53基因外显子7的损伤,有2个位点。未检测到TCA对大鼠p53基因的损伤作用。结论二氯乙酸的致癌作用可能与损伤p53基因有关,RDPCR技术检测靶组织p53基因的损伤作用与大鼠致癌试验的结果有很好的一致性。

Objective To study on the DNA damage of p53 induced by dichloroacetic acid（DCA） and trichloroacetic acid（TCA）, approve their genotoxicity and discuss molecular mechanism of their carcinogenic action. Methods Administered SD rats with DCA or TCA by i.p. injection, extracted DNA from rat＇s liver, and then used RDPCR to detect DNA damage of exon 7of p53 gene. Results Two hybridization bands were detected in treated group induced by DCA. It was indicated that DCA can result in DNA damage of exon 7of p53 gene of rat＇ s liver tissue, and there were two broken sites. It was not detected damage of exon 7 of p53 gene of rat induced by TCA. Conclusion There may be the relationship between DCA carcinogenic action and the damage of p53. The result that the damage of p53 of target tissue detected by RDPCR was consistent well with rat carcinogenic test.