Protective effect of estrogen on substantia nigral neuron in ovariectomized female rats

    TIAN Xueª²Wen, ZHANG Xiang, ZHANG Jianª²Ning

    Neurosurgical Institute of Chinese PLA, Xijing Hospital, Fourth Military Medical University, Xi¬ðan 710033, China

    ¡¾Abstract¡¿ AIM: To investigate the effects of estrogen on the substantia nigral neuron in female rats ovariectomized 7 d before and to explore the possibility of using estrogen to prevent and treat Parkinson¬ðs disease. METHODS: At 30 d after injection of 6ª²hydroxydopamine (6ª²OHDA) stereotaxically into the right side of the mesencephic ventral tegmental area and substantia nigra pars compacta of rats ovariectomized, immunocytochemical techniques were used to observe the TH positive cells of the substantia nigra and the number of TH positive cells was counted. The levels of estrogen in rats¬ð blood were detected after administration of estrogen. The results were analyzed by statistical methods. RESULTS: In the group with estrogen below the natural level, much fewer TH positive cells were observed compared with those in groups with natural level estrogen (-87¡À6, P<0.01). CONCLUSION: Estrogen plays an important role in protecting the substantia nigral dopaminergic neurons of female rats and its optimal level is the natural level. ......