Objective:To investigate the effect of puerarin on the expressions of brain-derived neurotrophic factor(BDNF)

tyrosin kinase B(TrkB)

caspase-3 in substantia nigra tissue of Parkinson's rats induced by 6-hydroxydopamine (6-OHDA). Method: Rat parkinson model was established

themodeling rats were randomly divided into 5 groups: model group

L-dopa group (40 mg·kg-1)

low-

medium-and high-dosage groups of puerarin (20

40

80 mg·kg-1). The drugs were intragastrically perfused daily for 30 consecutive days. The apoptosis of nerve cells in substantia nigra was observed by TUNEL assay. The expression of BDNF and TrkB in substantia nigra was assayed by Western blot analysis. The caspase-3 expression was tested by immunohistochemistry assay. Result: Compared with model control group

puerarin effectively reduced neuronal apoptosis levels in substantia nigra tissue of parkinson's rats (P<0.01)

and up-regulated the BDNF

TrkB protein levels in substantia nigra tissue (P<0.01). The number of caspase-3 immunoreactive cells was significantly decreased. Conclusion: The results demonstrate that puerarin has protective effect on the neuronal cells in substantia nigra of PD rats induced by 6-OHDA

probably the mechanism may be linked to neuronic repair or regeneration and reverse the process of apoptosis to improve the functions in substantia nigra.