Male Sprague-Dawley rats ranging in age from 20 to 110 days were injected with two doses of morphine sulphate, and examined for behavioral activation and catalepsy. Behavioral activation increased with age, while sensitivity to catalepsy declined. Ontogenetic and pharmacological responses suggest possible separate mediation of activation and catalepsy.

Interactions between excitatory amino acids and opioids were examined by studying the ability of the noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 to affect morphine catalepsy and lethality. MK-801 (0.3 mg/kg) reduced the ED50 for morphine-induced catalepsy from approximately 30 mg/kg to less than 10 mg/kg, and reduced the LD50 for morphine from approximately 100 mg/kg t...

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Abstract : Verapamil at 5, 10 and 20 mg/kg ip did not inhibit the conditioned avoidance response, neither induced catalepsy nor antagonised apomorphine stereotypy in rats indicating that these doses do not block the postsynaptic striatal D 2 and D 1 dopamine (DA) receptors. However, pretreatment with 10 and 20 mg/kg ip verapamil potentiated methamphetamine stereotypy and antagonised catalepsy i...

Acute blockade of dopamine D(2) receptors by the typical antipsychotic drug haloperidol leads to alterations in neuronal gene expression and behavior. In the dorsolateral striatum, the levels of mRNA for the immediate-early gene c-fos and the neuropeptide gene neurotensin/neuromedin N (NT/N) are significantly increased by haloperidol. An acute behavioral response to haloperidol is catalepsy, co...

The perphenazine and fluphenazine GABA esters 3 and 4 evaluated in rat models for antipsychotic activity displayed a significant decrease of catalepsy associated with increased prolactin blood levels. Efficacy was evaluated in the d-amphetamine-induced hyperactivity model, where perphenazine abolished hyperactivity and induced sedation and catalepsy, whereas 3 reduced hyperactivity without seda...

PURPOSE Several evidences show that serotonergic neurons play a role in the regulation of movements executed by the basal ganglia. Recently we have reported that single dose of buspirone improved 6-hydroxydopamine (6-OHDA) and haloperidol-induced catalepsy. This study is aimed to investigate effect of chronic intraperitoneal (i.p.) administration of buspirone on 6-OHDA-induced catalepsy in male...