MODIFICATION OF CERTAIN CENTRAL NERVOUS EFFECTS OF HALOPERIDOL DURING LONG-TERM TREATMENT IN MOUSE AND RAT

The chronic administration of haloperidol to mice over periods of 1 week to 3 weeks has been shown not to decrease the anti-amphetamine properties of the compound, as measured by determining group toxicity and the inhibition of enhanced metabolic rate; on the other hand, the cataleptogenic effect of the drug slightly and transiently decreased after long-term treatment, the potentiation of pentobarbital narcosis being markedly reduced. In rats, prolonged administration of haloperidol for 2 to 3 months failed to affect cataleptogenic activity, diminished the potentiating effect on pentobarbital narcosis, and had no influence on the inhibition of amphetamine-induced stereotypy. The inhibition of amphetamine hypermotility, however, exhibited a considerably altered pattern, developing much more slowly but increasing gradually. The chronic administration of haloperidol has been shown to have no effect on brain noradrenaline and dopamine levels in either the mouse or the rat. © 1969 Springer-Verlag.