Aim Baicalein is the major flavonoid obtained from the Scutellaria root.Our previous studies have demonstrated that baicalein has a clear positive effect on recovery in an experimental model of Parkinsonism.The purpose of this study was to investigate the role of baicalein in modulating dopamine (DA) metabolism in PC12 cells and to explore possible mechanisms of its actions.Methods The intracellular content and extracellular release of DA in both rotenonetreated and untreated PC12 cells were examined.Second, PC12 cells were first pretreated with baicalein (10 μmol · L1) for 10 min, and then incubated with or without ionomycin (5 μmol · L1) for 10 min to test whether shortterm exposure to baicalein affected calciumdependent or spontaneous DA release.Third, the intracellular and extracellular contents of DA and its related metabolites were examined.After treatment with baicalein for 24 h, the The tyrosine hydroxylase (TH), monoamine oxidase B (MAOB), catecholOmethyltransferase(COMT) and dopamine transporter (DAT) were detected by immunoblot analysis.Results The results showed that baicalein prevented rotenoneinduced cytotoxicity and significantly increased the DA content in both rotenonetreated and untreated PC12 cells.Furthermore, it had no effect on ionomycininduced or spontaneous DA release after shortterm exposure but significantly increased DA content in a timeand dosedependent manner after treatment for 6 h.Baicalein also significantly decreased the intracellular and extracellular homovanillic acid (HVA)content but increased the intracellular 3,4dihydroxy phenylacetic acid (DOPAC) content.Finally, baicalein significantly decreased the expression of COMT and DAT, but it had no effect on the expression of TH and MAOB.Conclusion These data suggest that bacalein has the ability to increase DA content and modulate DA metabolism by inhibiting the expression of COMT and DAT.Our study provides evidence that baicalein may be a potential antiPD drug that merits further study.