Potentiation of haloperidol catalepsy by microinjections of nicotine into the striatum or pons in rats.

It was reported that systemic administration of nicotine in rats potentiated the cataleptogenic effect of haloperidol. Moreover, addition of nicotine to the treatment with haloperidol in patients suffering from the Gilles de la Tourette's syndrome resulted in reduction in frequency and severity of tics. In the present article we report results of experiments aimed at investigating the role of striatum and pontine reticular formation in the synergistic relations between the two drugs. Nicotine was microinjected directly into the striatum or pontine reticular formation of rats and its cataleptogenic effects were studied when given alone or in combination with systemical injections of haloperidol. It was found that nicotine has cataleptogenic effects when microinjected both into the striatum and pontine reticular formation. The synergism between the two drugs occurred both after microinjections into the striatum and pontine reticular formation.