Objective To study the compatibility law and optimal compatibility proportion of Pingpa Decoction for Parkinson’s disease（PD）.Methods Totally 112 C57/BL male mice were induced into PD models with intraperitoneal injection of 1-methyl-4-phenyl-1

2

3

6-tetrahydropyridine（MPTP）and randomized into 8Chinese medication groups

with 14 in each.According to the L8（27）orthogonal array

each group was gavaged with corresponding Pingpa Decoction[Yinxingye（Folium Ginkgo）

Roucongrong（Herba Cistanches）

Luobuma（Folium Apocyni Veneti）and Shangengcai（Lobelia sessilifolia Lamb）]once daily for 10consecutive days.The dosage in Chinese medication group 1

group 2to 7and group 8was 12g/（kg·d）

24g/（kg·d）and 48g/（kg·d）respectively.High performance liquid chromatography-electrochemical detector（HPLC-ECD）was used to determine the contents of dopamine（DA）

3

4-dihydroxyphenylacetic acid（DOPAC）and homovanillic acid（HVA）in striatum.Immunohistochemical method was used to observe the expression of tyrosine hydroxylase（TH）in the substantia nigra.Results Banded positive neurons

spindle or tapered cell body

dark brown yellow to pale yellow cytoplasm

axon fibers and missing intercellular fibers could be seen in the substantia nigra of mice in each group.The therapeutic effect of Pingpa Decoction for PD was influenced by Yinxingye

Roucongrong

Shangengcai and Luobuma in order

especially Yinxingye and the interaction of Yinxingye and Roucongrong（P<0.05）.Conclusion The optimal compatibility proportion of Pingpa Decoction is 20g Yinxingye

40g Roucongrong

20g Luobuma and 20g Shangengcai.