3-methyl-1-phenyl-2-pyrazolin-5-one (edaravone), an effective free radical 
scavenger, provides neuroprotection in stroke models and patients. In this 
study, we investigated its neuroprotective effects in a chronic rotenone rat 
model for Parkinson's disease. Here we showed that a five-week treatment with 
edaravone abolished rotenone's activity to induce catalepsy, damage mitochondria 
and degenerate dopamine neurons in the midbrain of rotenone-treated rats. This 
abolishment was attributable at least partly to edaravone's inhibition of 
rotenone-induced reactive oxygen species production or apoptotic promoter Bax 
expression and its up-regulation of the vesicular monoamine transporter 2 
(VMAT2) expression. Collectively, edaravone may provide novel clinical 
therapeutics for PD.