ABSTRACT
In the present study, the effects of a single administration of buspirone (0.1, 0.3, 1.0, and 3.0 mg/kg sc-30 min before testing) on three dopamine-related behaviors were evaluated in 4-month old male Wistar rats (7-10 animals per group). Buspirone decreased haloperidol (2.0 mg/kg ip)-induced catalepsy in a dose-dependent manner (from 7.30 to 5.09 1n of s compared to the untreated control group). Apomorphine (0.06 mg/kg sc)-induced yawning was also dose-dependently reduced (from 26.7 to 0.9 yawns in 30 min) and so was apomorphine (1.0 mg/kg sc)-induced stereotypy (from 32.9 to 5.9, sum of scores). The present results indicate that buspirone presents unique pharmacological effects related to dopaminergic transmission not only in biochemical but also in behavioral terms
Subject(s)
Animals , Male , Rats , Buspirone/administration & dosage , Catalepsy/drug therapy , Stereotyped Behavior/drug effects , Yawning/drug effects , Analysis of Variance , Apomorphine/antagonists & inhibitors , Buspirone/pharmacology , Catalepsy/chemically induced , Haloperidol/antagonists & inhibitors , Rats, WistarABSTRACT
Neuroleptcs such as chlorpromazine and haloperidol are capable of inducing catalepsy in rodents. Non-selective 5-hydroxytryptamine (5-HT) antagonists such as methysergide reduce the cataleptic effect of haloperidol. The present study was designed to evaluate the particpation of 5-HT-1A receptors in chlorpromazine-induced catalepsy in mice. Pundolol and buspirone, two putative 5-HT-1A receptor ligands, were used. Pretreatment with these drugs reduced the cataleptic effect of chlorpromazine. Clomipramine, a 5-HT neuronal uptake blocker, reversed the inhibitory effect of buspirone. Pretreatment with clomipramine alone caused a potentiation of neuroleptic-induced catalepsy. These results suggest that central 5-HT-1A receptors play an important role in neuroleptic-induced catalepsy in mice