黄曲霉素B1-DNA加合物的实验研究

INVESTIGATION ON DNA\|AFB1 ADDUCTS IN VITRO AND IN VIVO BY 32P\|POSTLABLEING

用３２Ｐ后标记的方法测小牛胸腺ＤＮＡ和黄曲霉素Ｂ１体外反应产物里的ＤＮＡＡＦＢ加合物，发现有４种不同的ＤＮＡ加合物，加合物含量的ＲＡＬ＝１０８（加合物）／１０７（正常核酸），对比用ＤＮＡ的４种碱基和ＡＦＢ１反应所形成的加合物，发现有３种ＤＮＡＡＦＢ１的加合物是来自鸟嘌呤碱基被修饰所形成的，占ＤＮＡ加合物总量的９０％．用定量的黄曲霉素Ｂ１腹腔注射入大白鼠中，２４ｈ取其肝、肾、肺、脾等组织，加合物的总含量分别是肝＞肾＞肺＞脾．用ＡＲＯＣＬＯＲ诱导能促进各组织中ＤＮＡ加合物的形成，但是对不同的组织有不同的促进作用．

DNA\|AFB1 adducts in the samples reacted with DNA and AFB1 (in vitro) and in various organs of SD rat treated with AFB1 have been analyzed by 32P\|postlabeling. the results showed that four DNA\|AFB1 adducts were detected and RAL of the four DNA adduct were (617—4486) adduct/10\+9 normal nucleotide. The primary site of DNA modification was deoxyguanosine in vitro. Some DNA\|AFB1 adducts were detected in organs of rat (live, kidney, lung, spleen) and extent of DNA adduxts formation in the organs was liver>kidney>lung>spleen.