苯并(a)芘代谢产物诱发BALB/3T3细胞程序外DNA合成(UDS)的研究

Measurement of Unscheduled DMA Synthesis in BALB/3T3 Cells Following Exposure to BaP Metabolites

本实验采用单标记和双标记法,分别检测4种苯并(a)芘代谢产物(anti-BPDE,syn-BPDE,3-OH-BP和9-OH-BP)对BALB/3T3细胞DNA合成和程序外DNA合成(UDS)的影响,结果表明,anti-BPDE、syn-BPDE、3-OH-BP和9-OH-BP均在不同程度上使BALB/3T3细胞DNA合成增加,但只有anti-BPDE、3-OH-BP和9-OH-BP可诱发BALB/3T3细胞的UDS,说明这些苯并(a)芘代谢产物可损伤BALB/3T3细胞的DNA,同时,这种效应与苯并(a)芘代谢产物的立体结构有关。

Four BaP metabolites (anti-BPDE, syn-BPDE, 3-OH-BP and 9-OH-BP) were assessed for their potential to induce unscheduled DNA synthesis (UDS) in BALB/3T3 cells. BALB/3T3 cells-were cultured with E9888 (aginine-free medium) and treated with 14C-TdR (O.OlCi/ml) for 72 hrs, subsequently 'H-TdR (l//Ci/ml) and BaP metabolites for another 24 hrs. Radioactivity was measured with LS6000 liquid scintillation system. The results showed that all metabolites can increased DNA synthesis but only anti-BPDE, 3-OH-BP and 9-OH-BP can induce UDS. Anti-BPDE induce UDS in a relatively high level. Compared with 3-OH-BP and 9-OH-BP. Syn - BPDE is completely different from anti-BPDE in stereo-structure and may be not suitable to bind with DNA. It is suggested that DNA of BALB/3T3 cells can be damaged by BaP metabolites and DNA damage is related to slereo-structure of BaP metabolites.