Abstract: To explore correlation between proto oncogene c-fos expression in the striatum and dopaminergic neurons loss in the midbrain, twenty rats with unilateral 6-OHDA-lesioned dopaminergic neurons in the midbrain, were used for PD models which were divided into two groups, according to postoperative survival time. The abnormal rotations and c-fos expression could be induced by injection of apomorphine in all these rat models. Distribution of TH positive neurons and c-fos positive cells was observed with immunohistochemistry. The immunohistochemical staining of brain sections showed that a significant loss of TH positive and TH intensively positive neurons in the lesion side could be observed from the rats survived 7 days after lesion and completely disappeared from the rats survived 2 months. In addition, an expression of c-fos gene could be induced in the caudate putamen by injection of apomorphine from the rats survived 2 months in the experiment group. The results indicated that proto oncogene c-fos expression in the caudate putamen could reflect dopaminergic neurons lesion of PD. Whether c-fos expression could be induced or not depended on the degree of dopaminergic neurons lesion.

Key words: Parkinson disease, tyrosine hydroxylase, proto oncogene, c-fos, immunohistochemistry