关键词: 热休克, γH2AX, DNA损伤, 遗传毒性

Abstract: BACKGROUND ＆ AIM: To study whether heat shock could induce the formation of γH2AX foci in CHL cells, and the effect of heat shock on N-methyl-N＇-nitro-N-nitrosoguanidine(MNNG)-induced γH2AX foci formation. MATERIALS AND METHODS: The cytotoxic effect of heat shock was evaluated by MTT test.The phosphorylation of γH2AX was assessed using immunofluorescent microscopy and flow cytometry. RESULTS: MTT test showed that heat shock decreased cell viability.There was no significant difference in the number of γH2AX foci between heat-shock treated group and control group as shown by immunofluorescent microscopy. Flow cytometry analysis revealed that pre-heat shock followed by MNNG treatment decreased the mean γH2AX fluorescent intensity from 0.316±0.042 in the MNNG-treatment alone group to 0.194±0.011. CONCLUSION: Heat shock did not induce γH2AX foci formation in CHL cells.In addition, heat shock could inhibit the phosphorylation of H2AX induced by MNNG.

Key words: heat shock, γH2AX, DNA damage, genotoxicity