[Effects of anticholinergics and clozapine on the activation of the striatal dopaminergic system in the rat by haloperidol. Neurochemical findings (author's transl)].

The increase in the concentration of homovanillic acid (HVA) in the haloperidol for 6 days compared to a single administration of the drug. The induction of tolerance is probably due to a functional modification of the striatal dopamine (DA)-receptors after repeated administration of the neuroleptic. Atropine given in combination with haloperidol enhances the induction of tolerance. Clozapine (20 mg/kg orally) had no such effect.