Interaction of antidepressants with antiparkinsonian agents in rats

The influence of antidepressants: nomifensine, imipramine, amitriptyline and trazodone on the effect of antiparkinsonian agents: trihexyphenidil and L-DOPA + carbidopa mixture (sinemet) in the model of haloperidol catalepsy was investigated in rats. In some experiments deprenyl, a selective MAO-B inhibitor, was used. It was found that antidepressant drugs in doses not influencing haloperidol catalepsy enhanced significantly the anticataleptic effect of trihexyphenidil and L-DOPA + carbidopa. The most effective in the interaction with both antiparkinsonian agents was nomifensine. Imipramine and trazodone potentiated anticataleptic effect of L-DOPA + carbidopa more strongly than those of trihexyphenidil. The most potent anticataleptic effect was observed after combined treatment of rats with deprenyl and L-DOPA + carbidopa.