The effect of 5-hydroxytrytamine synthesis inhibitors on neuroleptic-induced catalepsy in rats.

The influence of factors which inhibit 5-hydoxytryptamine (5-HT) synthesis, i.e. p-chlorophenylalanine (PCPA) and p-chloroamphetamine (PCA), on cataleptic action of the neuroleptics: spiroperiodol, pimozide, reserpine and fluphenazine was studied. PCPA showed weak anticataleptic activity in reserpine-induced catalepsy but had no effect on catalepsy induced by spiroperidol or fluphenazine. PCPA also tended to depress the cataleptic effect of pimozide, but the results were not statistically significant. PCA had no influence on catalepsy induced by neuroleptics from the group of butyrophenones, potentiated the cataleptic action of reserpine in the dose of 5 mg/kg, and suppressed catalepsy induced by reserpine in the dose of 10 mg/kg. The results suggest that under conditions of the inhibition of the inhibition of 5-HT synthesis the cataleptic action of some neuroleptics may be slightly modified.