Experimental Study on the Neuronal Toxical Effect of Levodopa and the Inhibition of Ginkgo Biloba Extract on Parkinson Disease in Rats

Objective: To observe neuronal toxical effect of Levodopa and investigate whether using Levodopa together with EGb is an ideal, workable method to treat Parkinson disease. Methods: In this study, the rat models of Parkinson disease (PD) were made by injecting stereotaxically 6-OHDA to right side of the mesencephic ventral tegmental area (VTA) and substantia nigra pars compacta (SNc). We used rotational behaviour, TUNEL, immunocytochemical, Nissl’s body staining methods to observe the difference between Levodopa (50mg/kg/d×3d, ×5d, ×7d, L-dopa group) and the combination use of Levodopa and EGb (100 mg/kg/d, E-D group). Results: The numbers of apoptosis and rotation, bFGF protein expression in the L-dopa group surpassed those in the E-D group (P<0.05). The number of Nissl cells in the L-dopa group was fewer than the E-D group. Conclusion: Levodopa has neurological toxical effect. EGb may decrease the toxicity of levodopa. The combination use of Ginkgo biloba extract (EGb) and Levodopa is a workable method to treat Parkinson disease and is better than using Levodopa alone.