To study the effects of6 - hydroxydopamine(6 - OHDA) and reduced glutathione(GSH) on the nigral dopaminergic neurons in brain slices in vitro,immolunohistochem ical technique was used to observe the changes of TH - stained neurons,including cell bodies and the dendrites,in the substantia nigra (SN) of midbrain slices of rats after incubation for 1h in the presence of GSH 15 m in before and during the period of incubation with6 - OHDA.The results showed thatcell bodies rem ained intact but dendrites were fragm ented and truncated after treatment with6 - OHDA.The antioxidant GSH alone did not significantly affect the dendrites of SN neurons but prevented6 - O- HDA- induced damage of dendrites.It was concluded that glutathione m ay prevent6 - OHDA- in- duced dopam inergic neurodegeneration and play a protective role in dopaminergic neurons. To study the effects of 6 - hydroxydopamine (6 - OHDA) and reduced glutathione (GSH) on the nigral dopaminergic neurons in brain slices in vitro, immolunohistochemical technique was used to observe the changes of TH - stained neurons, including cell bodies and the dendrites , in the substantia nigra (SN) of midbrain slices of rats after incubation for 1 h in the presence of GSH 15 m in before and during the period of incubation with 6 - OHDA. These results showed thatcell bodies rem ained intact but dendrites were fragm ented and truncated after treatment with 6 - OHDA. antioxidant GSH alone did not significantly affect the dendrites of SN neurons but prevented 6 - O-HDA-induced damage of dendrites. It was said that glutathione m ay prevent 6-OHDA-in- duced dopam inergic neurodegeneration and play a protective role in dopaminergic neurons.