<正>Objective: To investigate the mechanism of oxidative stress in rotenone neurotoxicity to dopaminergic neuron PC12. Methods: High differentiated PC12 cells as dopaminergic neurons were treated by different concentrations of rotenone. The morphology was observed with inverted phase contrast microscope and transmission electron microscope. Cell viability and proliferation inhibition were assessed by MTT. SOD and MDA were detected with biochemical assay. And the specific fluorescent probe （DCF-DA） was used to examine ROS in PC12 cells. Results: After treated with rotenone for 24 h

most of the PC12 cells became smaller and rounder. The process of axon was reduced

shortened or broken in a time and concentration dependent manner. The mitochondrial structure and metabolism were changed. Endoplasmic reticulum expanded and the free ribosome increased. Compared with the control group

cell proliferation inhibition increased and cell viability decreased. SOD increased and MDA decreased. The intensity of fluorescence was more obvious in PC12 cells treated by rotenone compared with control group. Conclusion : Rotenone is neurotoxic to cultured dopaminergic neuron PC12. Rotenone might exert this effect through the metabolism of oxidative stress on the pathogenesis of the neuron.