关键词: 多氯联苯126, 苯并(a)芘, 联合作用, 微核, CYP1A1

Abstract: BACKGROUND ＆ AIM: To study effects of polychlorinated biphenyl PCB126 on B(a)P_induced genotoxicity. MATERIALS AND METHODS: HepG2 cells were treated either with different concentrations of PCB126 (0.01, 0.10,1.00 nmol/L) alone,or with different concentrations of PCB126 for 48 h then with B(a)P (50 μmol/L) and PCB126 together for another 24 h. DMSO and 3_MC were used as solvent control and positive control, respectively. EROD activity and micronuclei(MN) formation were analyzed through fluorescence spectrophotometry and a cytokinesis_block micronucleus(CBMN) assay, respectively. The frequencies of MN(‰) and nuclei division index (NDI) were calculated. RESULTS: Comparing to solvent control, EROD levels increased markedly in HepG2 cells treated with PCB126 (0.01, 0.10, 1.00 nmol/L) and B(a)P (50 μmol/L) alone or together, and MN frequencies increased significantly only in HepG2 cells treated with B(a)P alone(P<0.05,P<0.01). Comparing to B(a)P treatment alone, the EROD levels and MN frequencies increased significantly in HepG2 cells treated with B(a)P and PCB126 (0.10,1.00 nmol/L) together(P<0.05,P<0.01). CONCLUSION: PCB126 at certain concentrations showed no genotoxic effect in HepG2 cells, but it might enhance the genotoxic properties of B(a)P.

Key words: PCB126, B(a)P, combined effect, micronuclei, CYP1A1