Experimental study of MPP+ toxicity to the growth and proliferation of PC12 cells

    ZHENG Gang, LUO Wenª²Jing, ZHANG Xueª²Ping, XU Wen, CHEN Jingª²Yuan

    Department of Occupational & Environmental Hygiene, School of Preventive Medicine, Fourth Military Medical University, Xi¬ðan 710033, China

    ¡¾Abstract¡¿ AIM: To study the toxicity of different doses of 1ª²Methylª²4ª²phenylpyridinium ion (MPP+) to rat pheochromocytoma PC12 cells in vitro. METHODS: PC12 cell cultures were exposed to MPP+ within a dose range of 100ª²700 ¦Ìmol/L. The inhibition of the cells during 7 d was determined by cell counting and MTT assay and the cell growth curve was made. The morphological changes were observed by transmission electron microscope and the apoptotic rate and cell cycle of the cells were monitored by flow cytometry analysis (FCM) at the same time. RESULTS: MPP+ at different concentrations (100, 300, 500, 700 ¦Ìmol/L) inhibited the growth and proliferation of PC12 cells in a doseª² and timeª²dependent manner and the cell growth curve changed accordingly. After a 4ª²day exposure of MPP+, from 100 to 700 ¦Ìmol/L, the cell survival rates decreased from 0.78 to 0.34 in comparison with those of the control (P<0.01). When coª²cultured with 300 ¦Ìmol/L MPP+, some apoptotic changes of the cells were observed under transmission electron microscope. FCM showed that after the exposure of 100, 300 ¦Ìmol/L MPP+, the total apoptotic rate of PC12 cells increased by 0.51 and 0.62, respectively (P<0.01). CONCLUSION: MPP+ can significantly inhibit the growth and proliferation of PC12 cells and the induction of apoptosis may be responsible for the inhibition. ......