紫外线照射致小鼠皮基底细胞DNA损伤的剂量-效应研究

Study of Dose-Effect Relationship of UV Irradiation on Bassal Cell UDS of Mouse Skin

观察不同剂量的紫外线持续照射12周对小鼠皮肤基底细胞程序外DNA合成的影响发现:当紫外线剂量大于1/2最小红斑量(MED),一次照射即可使程序外DNA合成明显增加;对紫外线照射的时间-效应关系研究表明,大于1/2MED的紫外线照射,程序外DNA合成持续增加,而1/8MED组则无明显改变。提示剂量大于1/2MED的紫外线持续照射可能会对生物体细胞产生损伤。

In this papec,Unscheduled DNA Synthesis (UDS)of epithelial basal cells in mice was mea- sured affter 1/8, 1/2,1 and 3 MED ultraviolet irradiation for twelve weeks. The dose-effect relationship between UV irradiation dose and epithelial UDS was demonstrated.The exposing dose at level of 1/2 MED,the UDS level of basal cells was inceaseel significantly.For time-effect study,at the levl of 1/8 MED each day,the ch- ange of UDS is not significant. But more the 1/2 MED,UDS of basal cells are inceased conti- nuously.The resuits suggest that 1/8 MED UV irradiation is safe for these indices,longterm UV irradiation at the dose more than 1/2 MED each day may injure the skin.