Vitamin E attenuates the toxic effects of intrastriatal injection of 6-hydroxydopamine (6-OHDA) in rats: behavioral and biochemical evidence.

Unilateral 6-hydroxydopamine (6-OHDA) injections into the striatum lead to the development of apomorphine-induced rotation in rats. The circling behavior was associated with significant decreases in dopamine, dihydroxyphenylacetic acid and homovanillic acid in the ipsilateral striatum. Pretreatments with either D-alpha-tocopherol or all-racemic-alpha-tocopherol caused significant attenuation of both the behavioral and biochemical abnormalities. These results are discussed in terms of their support for the free radical hypothesis of Parkinson's disease and for the role of antioxidants in the treatment of this neurodegenerative disorder.