Ascorbate blocks amphetamine-induced turning behavior in rats with unilateral nigro-striatal lesions.

Unilateral nigro-striatal lesions were produced in rats using 6-hydroxydopamine. Intraperitoneal injections of amphetamine induced circling behavior in these rats due to release of striatal dopamine contralateral to the lesion. Intraperitoneal injections of 1 g/kg of ascorbic acid elevated brain ascorbate. Ascorbate, like other drugs blocking dopamine receptors, attenuated the amphetamine-induced turning behavior. Thus, ascorbic acid might have a role in regulating dopaminergic transmission and could be of therapeutic value in disorders involving functional dopamine excess.