苯DNA加合物的组织分布及其与细胞遗传毒性的关系

DNA adducts distribution in tissues and it's correlation with cytotoxicity in mice exposure to benzene

用Ｐ１增强的３２Ｐ－后标记方法测定了经腹腔注射染苯小鼠不同组织ＤＮＡ加合物的分布及其与苯引起的外周血白细胞（ＷＢＣ）减少、淋巴细胞微核形成及骨髓细胞染色体畸变的关系。结果表明：１．苯在小鼠骨髓、肝脏和外周血ＷＢＣ均可形成ＤＮＡ加合物，其加合物含量以骨髓最高，肝脏次之，ＷＢＣ最低。本结果与苯的代谢及毒性作用特点相一致。２．ＤＮＡ加合物形成与细胞毒性有关系，ＤＮＡ加合物量增加，淋巴细胞微核及骨髓细胞染色体畸变亦增加，而外周血白细胞数明显减少，显示细胞遗传毒性和细胞毒性均增大。本研究为ＤＮＡ加合物作为生物学监测指标，筛选高危人群提供了有力的实验依据。

DNA adducts distribution in tissues and it's correlation with cytotoxicities were studied in mice dosed IP with benzene. DNA adducts were analyzed by 32P-postlabeling assay. The DNA adducts were found in DNA from white blood cell (WBC), myelocyte of bone marrow and liver cell. The content of adducts in bone marrow,liver cell WBC was 13.8×10-7,11.3 ×10-7 and 10.4 ×10-7 respectively. The relationship between DNA adducts and cyttoxicities was observed. The increase in DNA adduct content consists with the increase in micronuclei and chromosome aberration,but with the decrease of WBC count. It shows that the increased micronuclei and chromosome aberration are associated with DNA lesion. It may reveal the molecular machenism of benzene toxicity, mutagenicity and carcinogenicity.